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Ischemic stroke (IS) remains a leading cause of long-term disability and mortality worldwide, with recovery outcomes shaped by the interplay between acute vascular injury, pre-existing comorbidities, and individual molecular profiles. Common risk factors-such as diabetes mellitus, atrial fibrillation, hypertension, and dyslipidemia-not only increase stroke susceptibility but also impair neurovascular repair by perpetuating systemic inflammation, endothelial dysfunction, and impaired neuroplasticity. Aging remains an underexplored determinant of epigenetic remodeling in stroke. Beyond these clinical determinants, genetic and epigenetic mechanisms contribute substantially to stroke heterogeneity. Genome-wide association studies (GWAS) have identified loci such as HDAC9, PATJ, PTCH1, and ABO that modulate inflammation, oxidative stress, and vascular remodeling. Complementary epigenetic pathways, including DNA methylation, histone acetylation, and circular RNAs (circRNAs), dynamically regulate gene expression in response to ischemia and comorbid influences, encoding a persistent "molecular memory" that shapes both injury and repair. Functional studies reveal that circRNAs orchestrate apoptosis, angiogenesis, and synaptic remodeling, while selective DNMT and HDAC inhibition can restore neurovascular integrity in experimental models. Recent multi-omics and longitudinal approaches demonstrate that these molecular signatures evolve across acute, subacute, and chronic phases of recovery, yet clinical translation remains limited. Aging and chronic comorbidities further modify epigenetic programs, reducing repair capacity. Although genotype-guided antiplatelet therapy illustrates the feasibility of personalized stroke care, broader genomics- and epigenetics-informed interventions require rigorous validation. This review integrates current knowledge on the interplay between vascular comorbidities, genetic predisposition, and epigenetic regulation in shaping stroke recovery. Understanding these interactions is essential for developing precision medicine approaches that enhance functional outcomes and reduce recurrence in stroke survivors.Integrating multi-omics profiling with comorbidity stratification, functional validation, and longitudinal biomarker tracking will be pivotal to achieving actionable precision medicine and improving outcomes in stroke survivors. Show less

Drought and water scarcity, exacerbated by global warming, are enormous threats to global food sustainability and security. Poultry, in particular, are highly impacted by adverse environmental stressors. As nutrient absorption and intestinal integrity are critical for growth and performance, understanding the impact on the broiler gastrointestinal tract is highly relevant. Here, we examined the effect of chronic cyclic heat stress (HS) on the jejunal expression profile of tight-junction, gap-junction, adherens, and desmosome genes in the 4th generation of broiler lines divergently selected for low (LWE)- and high-water efficiency (HWE). Male HWE and LWE broilers (n = 240/line) were allotted to 12 environmental chambers (2 floor pens/chamber, 6 chambers/line, 20 birds/pen) and were exposed to cyclic HS (36°C for 9h/day from 9:00 am to 6:00 pm) or thermoneutral conditions (25°C) from day 29 to 49 of age in a 2 × 2 factorial design. Growth performance and mortality were recorded. At day 49, jejunal tissues were collected for molecular analyses using real-time quantitative PCR and immunoblot. Jejunal gene expression of multiple gut integrity factors were higher (P < 0.05) in the HWE as compared to the LWE lines, including claudin 22 (CLDN22), -34, occluding (OCDN), zona-occludin-2 (ZO-2), gap junction alpha1 (GJA1), GJA3, GJC1, and cadherin 1 (CDH1). CLDN8, -20, -25, -4, GJC2, and GJD2 were also greater (P < 0.05) in HWE, but were additionally downregulated (P < 0.05) during HS. Conversely PALS1-associated tight junction protein (PATJ) and desmocollin 1 (DSC1) mRNAs were significantly downregulated in the HWE as compared to the LWE broilers. Significant interactions between the line and environment were seen in CLDN1, where the expression was decreased in the LWE but increased in the HWE in HS. Additionally, CLDN15 and -16 genes were greatest in the HWE under TN conditions, while catenin alpha 2 (CTNNA2) was highest in the HWE during HS. Overall, the jejunal expression profile of key genes associated with intestinal barrier integrity likely contributes to the water efficiency phenotype and the response of these birds to HS. Show less

The molecular features determining the risk of metachronous metastases in clear cell renal cell carcinoma (ccRCC) are poorly defined. This study aimed to identify molecular factors associated with the risk of metachronous metastasis. Using a systematic tumor transcriptome deconvolution approach, we investigated the genomic and transcriptomic profiles of 192 ccRCC primary tumors with extended clinical follow-up to identify cancer- and stromal cell-specific molecular features associated with metastatic risk. Based on these features, we applied multivariate Cox regression to develop a compact 5-gene predictive model for metachronous metastasis. At the genomic level, we identify a significantly higher frequency of copy number loss at 1p31-36 in primary tumors that later progress with metastases. Tumor transcriptome deconvolution identifies significant down-regulation of epithelial cell polarity, including PATJ (1p31), and fatty acid metabolism, including CYP4A11 (1p33), in cancer cells of tumors that develop metastatic progression. We develop and benchmark a compact 5-gene predictive model (5G) that demonstrates improved accuracy over existing ccRCC gene signatures in the prediction of metachronous metastasis risk. Overall, our study highlights convergent genomic and transcriptomic alterations in chromosome 1p, driving dysregulation of epithelial cell polarity and fatty acid metabolism, as putative risk factors of metachronous metastasis in ccRCC. Show less

This study aims to elucidate the regulatory mechanisms of host genetics on the porcine gut microbiota and their subsequent impact on the feed conversion ratio (FCR). While initial genome-wide association studies (GWAS) did not identify significant SNPs directly associated with FCR, we investigated the gut microbiota as a potential intermediate phenotype influencing feed efficiency. Nonmetric multidimensional scaling (NMDS) based on Bray–Curtis distances demonstrated a distinct separation in microbial community structure between the high-feed conversion ratio (HFCR) and low-feed conversion ratio (LFCR) groups (stress = 0.19), suggesting a link between FCR and gut microbial composition. Furthermore, a significant, albeit weak, negative correlation was observed between the genomic relatedness matrices and microbial Bray‒Curtis dissimilarity ( The online version contains supplementary material available at 10.1186/s42523-026-00527-y. Show less

Cystic kidney disease and related ciliopathies are caused by pathogenic variants in genes that commonly result in ciliary dysfunction. For a substantial number of individuals affected by those cilia-related diseases, the causative gene remains unknown. Using massively parallel sequencing, we here identified a pathogenic bi-allelic variant in the gene encoding PALS1-associated tight junction protein ([PATJ] also known as inactivation-no-afterpotential D-like, INADL) in an individual with ciliopathy. The affected fetus carried the homozygous truncating PATJ nonsense variant c.830delC (p.Pro277fsX), and presented with a syndromic phenotype mainly characterized by polycystic kidney disease and hydrocephalus. Using zebrafish (Danio rerio) as a vertebrate in vivo model organism, we could validate our patient findings and demonstrated a ciliopathy phenotype. In addition, we were able to address a hitherto not described role of Patj for cilia formation and function. Taken together, with the Crumbs cell polarity complex member PATJ, we add a new member to the large family of ciliopathy-related human disease proteins that is different from the classical ciliopathy protein classes, and may offer new perspectives for drug development. Show less

Current guidelines recommend avoiding activities with the risk of contact during pregnancy, despite a lack of empirical data to support this recommendation. As a result, individuals who participate in contact and collision sports such as football or rugby are often confronted with difficult decisions and, in the absence of clear guidance, may resort to making choices based on personal experience, limited advice, or fear. We aimed to examine the impact of continued participation in contact sport during pregnancy on maternal and fetal health outcomes. We conducted an online survey study of individuals (≥ 18 years of age) who participated in contact or collision sports during pregnancy. The survey collected self-reported information on participant demographics, sport participation (type, hours, and contact exposure) from pre-conception to postpartum, maternal and infant health outcomes, feelings towards continuing/stopping participation in sport, and medical advice received during the perinatal period. Odds ratios or relative risk ratios with 95% confidence intervals were calculated for all categorical outcomes using regression adjusted for relevant covariates to compare outcomes in individuals who stopped participating in contact sport ≤ 12 weeks and > 12 weeks gestation as well as individuals who did and did not sustain a hit (contact) during pregnancy. Between September 2023 and February 2024, 395 participants (age 34.6 ± 5.0, months postpartum 27.2 ± 34.3; primarily from Australia, Canada, the UK, and the USA) were recruited to participate in the survey. Participants participated in contact sports for an average of 12.8 ± 6.4 weeks of pregnancy with 84 individuals sustaining hard hits and 114 individuals sustaining cumulative low impact contact. Participants reported partaking in a total of 11,687.2 h of contact exposure during pregnancy and the rate of adverse events was 1.11 per 1000 h of exposure. Overall, continued participation in contact sport during pregnancy was associated with better mental health status. Over half of participants stated that they had concerns about participating in contact sports during their pregnancy; however, 90% felt "happy" or "very happy" about continuing their sport during pregnancy. Pregnant individuals continue to participate in contact sports during pregnancy. Participants who continued participating in contact sports were more likely to report decreased depression. Continued participation in contact activities was not associated with the odds of other maternal or fetal complications during pregnancy or the postpartum period. Further investigation is required to direct safe participation in contact sports during pregnancy. Show less

The highly organized structures of the immunological synapse (IS) are crucial for T cell activation. PDZ domains might be involved in the formation of the IS by serving as docking sites for protein interactions. In this study, we investigate the role of the PALS1-associated tight junction protein (PATJ), which contains 10 PDZ domains, in the formation of IS and its subsequent impact on T cell activation. To elucidate the function of PATJ, we generated murine models with conditional T cell-specific knockout of We observed a rapid increase in PATJ expression during T cell activation. Conditional knockout of Our study reveals an important role of PATJ in the formation of IS and provides an approach to improve the efficacy of CAR-T therapy. Show less

Epithelial cells are inherently contractile and in homeostasis, tissue integrity is maintained by balancing the uneven contractile forces in neighboring cells at the cell-cell interface. By contrast, epithelial cells can utilize an imbalance in contractile force to communicate various information to induce tissue-wide response as in wound healing. Contractility is generated and processed at the apical junctional complex (AJC) by the dynamic behavior of the actin cytoskeleton. Calcium signaling can pattern cellular responses based on its reach and amplitude and the actin cytoskeleton is supported by its wide ranging effects on actin regulators. Calcium transients regulate various cell behaviors associated with actin remodeling, such as in damage response and developmental morphogenesis. Here, we report that calcium maintains an adaptive pool of AJC-associated actin that is sensitive to tension and encoded by calcium dynamics. For this, the recently identified epithelial polarity module Homer-MUPP1/PatJ is required. Homer regulates calcium signaling in various tissue contexts through interaction with numerous components of the endoplasmic reticulum (ER) and plasma membrane (PM) calcium signal toolkit. Knockout of either Homer or MUPP1/PatJ attenuated tension-induced calcium response and severely disrupted wound healing migration, which is dependent on guidance input through AJC tension. We also show that Homer is integral to early embryonic neurodevelopment as its suppression causes failure of neural tube closure. Our findings highlight the critical role of localized calcium dynamics on AJC actin remodeling and cellular behavior, elucidating the means of tissue coordination through intercellular tension. Show less

Heat stress (HS) has long posed a significant challenge to the poultry industry due to its adverse effects, such as depressed feed intake, decreased growth performance, and increased water consumption. Water efficiency (WE, conversion of water intake into body weight gain), although often neglected, is a key economic and production trait that is significantly affected by HS. Recently, we selected two broiler lines for high WE (HWE) and low WE (LWE) and showed a differential hypothalamic expression of genes involved in water homeostasis regulation. As the gut also plays a significant role in water absorption, the present study aimed to determine the effect of chronic HS on duodenal barrier integrity in LWE and HWE broilers. Male HWE and LWE chicks (240 chicks/line) were individually wing-banded for line identification, weighed, and placed in 12 controlled environmental chambers (2 pens/chambers). On day 29, birds were subjected to thermoneutral conditions (TN, 25 °C) or cyclic HS conditions (HS, 36 °C for 9 h/day from 9:00 a.m. to 6:00 p.m.) (120 birds/line/environment) for 3 weeks. On day 49, duodenal tissues were collected for histological, biochemical, and molecular analyses. Hematoxylin and eosin (H&E) staining revealed that HS significantly reduced villus height in the duodenum. Further analysis using qPCR showed that the mRNA expressions of intestinal barrier integrity-related genes, including claudins (CLDN1, 4, 5, 8, 16, and 22), PALS1-associated tight junction protein ( Show less

PALS1-associated tight junction (PATJ) protein is linked to metabolic disease and stroke in human genetic studies. Despite the recognized role of PATJ in cell polarization, its specific functions in metabolic disease and ischemic stroke recovery remain largely unexplored. We explored the functions of PATJ in an in vitro model and in vivo in C. elegans and mice. Using a mouse model of stroke, we found post-ischemic stroke duration-dependent increase of PATJ abundance in endothelial cells. PATJ knock-out (KO) HEK293 cells generated by CRISPR-Cas9 suggest roles for PATJ in cell proliferation, migration, mitochondrial stress response, and interactions with the Yes-associated protein (YAP)-1 signaling pathway. Notably, PATJ deletion altered YAP1 nuclear translocation. PATJ KO cells demonstrated transcriptional reprogramming based on RNA sequencing analysis, and identified dysregulation in genes central to vascular development, stress response, and metabolism, including RUNX1, HEY1, NUPR1, and HK2. Furthermore, we found that mpz-1, the homolog of PATJ, was significantly upregulated under hypoxic conditions in C. elegans. Knockdown of mpz-1 resulted in abnormal neuronal morphology and increased mortality, both of which were exacerbated by hypoxia exposure, indicating a critical protective role of PATJ/MPZ-1 in maintaining neuronal integrity and survival, particularly during oxygen deprivation stress relevant to ischemic stroke. These insights offer a new understanding of PATJ's regulatory functions within cellular and vascular physiology and help lay the groundwork for therapeutic strategies targeting PATJ-mediated pathways for stroke rehabilitation and neurovascular repair. Show less

A stroke's functional outcome presents vast variability among patients, which is influenced by age, sex, characteristics of the lesion, and genetic factors. However, there is little knowledge about stroke recovery genetics. Recently, some GWAS (Genome-Wide Association Studies) have highlighted the involvement of common or low-frequency variants near or within We performed a pilot study analyzing 90 exomes of extreme good and bad recovery (modified Rankin Scale score at 3 months, 0-1 versus 4-5) to select target genes involved in stroke recovery. To expand this study, 702 additional samples were sequenced by targeted next-generation sequencing capturing loci selected from the pilot study, GWASs, and literature input. Here, we performed continuous (modified Rankin Scale score, 0-6) and dichotomous (modified Rankin Scale score, 0-1 versus 3-6) analyses, yielding 1 candidate gene. All samples were selected by a retrospective cohort study from incidental stroke cases collected at Spanish Hospitals between 2000 and 2018. The identified VNN2 variants were assessed for protein structure and stability analysis, and an analysis of their effect on basal inflammation levels was performed using UK Biobank data. Our work identified rare coding variants in We propose that Show less

Diabetic retinopathy (DR) is one of the major complications of diabetes and can cause severe visual impairment. Blood-retina barrier (BRB) destruction resulted from chronic hyperglycemia underlines its major pathological process. However, current treatments have limited efficacy and may even cause serious complications. Remote ischemic conditioning (RIC), through repeated transient mechanical occlusion of limb blood vessels, has been confirmed to promote blood-brain barrier integrity after stroke, but its role in BRB disruption has not been elucidated. This study aimed to investigate the protective effects of RIC on the BRB in diabetic rats and its potential mechanisms. 48 Sprague-Dawley rats were randomly assigned to the Sham group, Sham + RIC group, diabetes mellitus (DM) group and DM+RIC group. The diabetic model was successfully induced by intraperitoneal injection of streptozotocin. RIC treatment was administered daily and lasted for 9 weeks. In functional analysis, RIC improved the retinal function based on electroretinogram data and reduced the leakage of BRB in diabetic rats. In proteomic analysis, tight junction pathway was enriched after RIC treatment, in which Patj gene was significantly increased. We also found that RIC increased mRNA levels of Patj, claudin-1 and zonula occludens (ZO)-1, protein expression of claudin-1 when compared with diabetic models. In conclusion, RIC slowed BRB damage in diabetic rats, which may be related to the preservation of tight junction proteins. RIC may be a promising protective strategy for the treatment of DR. Show less

The Kirgiz, a Turkic-speaking ethnic group with a rich nomadic heritage, represent a pivotal population for understanding human migration and adaptation in Central Asia. However, their genetic origins and admixture history remain largely unexplored. Here, we present the first comprehensive genomic study of Kirgiz populations from Xinjiang, China (XJ.KGZ, n = 36) and their counterparts in Kyrgyzstan (KRG), integrating genome-wide data of 2,406 global individuals. Our analyses reveal four primary ancestry components in XJ.KGZ: East Asian (41.7%), Siberian (25.6%), West Eurasian (25.2%), and South Asian (7.6%). Despite close genetic affinity (FST = 0.13%), XJ.KGZ and KRG diverged ∼447 years ago, with limited gene flow post-split. A two-wave admixture model elucidates their demographic history: an initial East-West Eurasian mixture ∼2,225 years ago, likely reflecting west-east contacts during the period of the Warring States and the Qin Dynasty, followed by secondary admixture events (∼875 to 425 years ago) linked to historical migrations under Mongol and post-Mongol rule. Local adaptation signatures implicate genes critical for cellular tight junction (e.g. PATJ), pathogen invasion (e.g. OR14I1), and cardiac functions (e.g. RYR2) with allele frequency deviations suggesting ancestry-specific selection. While no classical high-altitude adaptation genes (e.g. EPAS1) showed selection signals, RYR2 and C10orf67-implicated in hypoxia response in Tibetan fauna-displayed Western ancestry bias, hinting at convergent adaptation mechanisms. This study advances our understanding of the genetic makeup and admixture history of the Kirgiz people and provides novel insights into human dispersal in Central Asia. Show less

Skin color of poultry, an important economic trait, is related to breed, feed, environment, and other factors. In recent years, China's duck industry has developed rapidly, and duck products are welcomed by consumers. Different skin colors of ducks have different cooking methods. Black skinned duck, such as Yulin black duck, is more popular in China because they are considered more suitable for making soup, while other skin colors, such as Pekin duck, is used for roasting. In order to gain a deeper understanding of the genetic factors associated with differences in duck skin color, the transcriptomes and metabolomes of skin between Yulin black duck and Pekin duck from 15 (BSE15 vs. PSE15), 21 (BSE21 vs. PSE21) and 27 (BSE27 vs. PSE27) days of incubation were compared and analyzed. The transcriptome results showed that a total of 187 (118 up-regulated and 69 down-regulated), 417 (91 up-regulated and 326 down-regulated) and 137 (55 up-regulated and 82 down-regulated) differentially expressed genes (DEGs) were identified from BSE15 vs. PSE15, BSE21 vs. PSE21 and BSE27 vs. PSE27, respectively. The significantly enriched GO terms of biological process were positive regulation of melanin biosynthetic process, melanin biosynthetic process, cuticle development, melanin biosynthetic process from tyrosine, and melanocyte differentiation, which were potentially related to skin growth and development. Eleven significant pathways, highly enriched by DCT, TYR, ASIP, TYRP1, KIT, PHOSPHO2, CERS3, SGPP2, SPTLC3, DEGS2, PATJ, RBP7, AOX1, ETNPPL, HPGDS, and GAD1, were melanogenesis, tyrosine metabolism, vitamin B6 metabolism, sphingolipid metabolism, protein digestion and absorption, tight junction, alpha-linolenic acid metabolism, arachidonic acid metabolism, linoleic acid metabolism, nicotinate and nicotinamide metabolism, and alanine, aspartate and glutamate metabolism, which participated in regulating the development of duck skin during embryonic stage. The significantly different metabolites (SDMs) were mainly organoheterocyclic compounds, lipids and lipid-like molecules, organic oxygen compounds, organic acids and derivatives, including L-tyrosine, N-arachidonyl maleimide, glycerophospho-N-palmitoyl ethanolamine, LPE 22:4, and PC(0:0/18:0). which were mainly enriched in glycerophospholipid metabolism, arachidonic acid metabolism, linoleic acid metabolism, alpha-linoleic acid metabolism, and melanogenesis in metabolome, suggesting that these pathways may play important roles in skin development of duck during embryonic stage. Besides, the analysis of integrated transcriptome and metabolome indicated that the pathways, including glycerophospholipid metabolism, arachidonic acid metabolism, linoleic acid metabolism, and alpha-linolenic acid metabolism, could contribute to regulating skin development in embryonic duck. Our findings could help elucidate the genetic mechanisms underlying the development differences in duck skin color. Furthermore, the candidate genes and metabolites can be used to provide a valuable breeding strategy for the selection of specific duck breeds with ideal skin coloration. Show less

Signal-induced proliferation-associated 1 like 3 (SIPA1L3) is a member of the protein family. Very limited data are currently available regarding the role of SIPA1L3 in human carcinoma. Therefore, in this study, we investigated the expression pattern and function of SIPA1L3 in non-small cell lung cancer (NSCLC). We analyzed the distribution of SIPA1L3 in NSCLC specimens by immunohistochemistry, the relationship between SIPA1L3 expression and patient clinicopathological features, and investigated the effect of SIPA1L3 on cell growth and invasion in vivo and in vitro using small interfering RNA. Western blotting and immunoprecipitation were performed to demonstrate the interaction between SIPA1L3 and tight junction-associated angiomotin (AMOT) and Pals1-associtated tight junction protein. We found that SIPA1L3 was overexpressed in NSCLC clinical tissue samples and was associated with several clinicopathological factors. SIPA1L3 affects the proliferation and invasion of cancer cells both in vivo and in vitro. Using a SIPA1L3 mutant, we found that SIPA1L3 interacts with AMOT through its PDZ domain, which inhibits the binding of AMOT to Pals1-associtated tight junction protein and further decreases AMOT anchoring to tight junctions. Our findings suggested that SIPA1L3 promotes tumorigenesis in lung cancer cells through its PDZ domain-mediated interaction with AMOT, suggesting that SIPA1L3 is a novel candidate gene that contributes to the malignant phenotype of lung cancer. Show less

The evolutionarily conserved apical Crumbs (CRB) complex, consisting of the core components CRB3a (an isoform of CRB3), PALS1 and PATJ, plays a key role in epithelial cell-cell contact formation and cell polarization. Recently, we observed that deletion of one Pals1 allele in mice results in functional haploinsufficiency characterized by renal cysts. Here, to address the role of PALS1 at the cellular level, we generated CRISPR/Cas9-mediated PALS1-knockout MDCKII cell lines. The loss of PALS1 resulted in increased paracellular permeability, indicating an epithelial barrier defect. This defect was associated with a redistribution of several tight junction-associated proteins from bicellular to tricellular contacts. PALS1-dependent localization of tight junction proteins at bicellular junctions required its interaction with PATJ. Importantly, reestablishment of the tight junction belt upon transient F-actin depolymerization or upon Ca2+ removal was strongly delayed in PALS1-deficient cells. Additionally, the cytoskeleton regulator RhoA was redistributed from junctions into the cytosol under PALS1 knockout. Together, our data uncover a critical role of PALS1 in the coupling of tight junction proteins to the F-actin cytoskeleton, which ensures their correct distribution along bicellular junctions and the formation of tight epithelial barrier. Show less

Pancreatic ductal adenocarcinoma (PDAC) is a tumor with a dismal prognosis that arises from precursor lesions called pancreatic intraepithelial neoplasias (PanINs). Progression from low- to high-grade PanINs is considered as tumor initiation, and a deeper understanding of this switch is needed. Here, we show that synaptic molecule neuroligin-2 (NLGN2) is expressed by pancreatic exocrine cells and plays a crucial role in the regulation of contact inhibition and epithelial polarity, which characterize the switch from low- to high-grade PanIN. NLGN2 localizes to tight junctions in acinar cells, is diffusely distributed in the cytosol in low-grade PanINs and is lost in high-grade PanINs and in a high percentage of advanced PDACs. Mechanistically, NLGN2 is necessary for the formation of the PALS1/PATJ complex, which in turn induces contact inhibition by reducing YAP function. Our results provide novel insights into NLGN2 functions outside the nervous system and can be used to model PanIN progression. Show less

Through GWAS studies we identified PATJ associated with functional outcome after ischemic stroke (IS). The aim of this study was to determine PATJ role in brain endothelial cells (ECs) in the context of stroke outcome. PATJ expression analyses in patient's blood revealed that: (i) the risk allele of rs76221407 induces higher expression of PATJ, (ii) PATJ is downregulated 24 h after IS, and (iii) its expression is significantly lower in those patients with functional independence, measured at 3 months with the modified Rankin scale ((mRS) ≤2), compared to those patients with marked disability (mRS = 4-5). In mice brains, PATJ was also downregulated in the injured hemisphere at 48 h after ischemia. Oxygen-glucose deprivation and hypoxia-dependent of Hypoxia Inducible Factor-1α also caused PATJ depletion in ECs. To study the effects of PATJ downregulation, we generated PATJ-knockdown human microvascular ECs. Their transcriptomic profile evidenced a complex cell reprogramming involving Notch, TGF-ß, PI3K/Akt, and Hippo signaling that translates in morphological and functional changes compatible with endothelial to mesenchymal transition (EndMT). PATJ depletion caused loss of cell-cell adhesion, upregulation of metalloproteases, actin cytoskeleton remodeling, cytoplasmic accumulation of the signal transducer C-terminal transmembrane Mucin 1 (MUC1-C) and downregulation of Notch and Hippo signaling. The EndMT phenotype of PATJ-depleted cells was associated with the nuclear recruitment of MUC1-C, YAP/TAZ, β-catenin, and ZEB1. Our results suggest that PATJ downregulation 24 h after IS promotes EndMT, an initial step prior to secondary activation of a pro-angiogenic program. This effect is associated with functional independence suggesting that activation of EndMT shortly after stroke onset is beneficial for stroke recovery. Show less

In epithelia, apicobasal cell polarization is closely linked to cell-cell contact formation, both controlled by the conserved Crumbs (CRB) complex, which includes the transmembrane protein Crumbs (CRB3a) and adapter proteins PALS1, PATJ, and LIN7c. In MDCK II cells, a model for cell polarization, depletion of PALS1 - which binds to all CRB components - leads to defective cell polarization and improper distribution of tight junction proteins, resulting in severe epithelial barrier defects in 3D cyst models. This study investigated whether this phenotype is associated with transcriptional changes by analyzing wildtype (WT) and PALS1 knockout (KO) MDCK II cell lines grown under non-confluent conditions and in 3D cyst cultures. Our results indicate that the transition from non-confluent cells to 3D cysts involves numerous differentially expressed genes (DEGs) in both WT and KO cells. Importantly, the analyses revealed significant overlaps between WT and KO cells in their maturation processes, suggesting that most identified DEGs are linked to differentiation from non-confluent to polarized MDCK cells and likely not a result of PALS1 deficiency. Gene Ontology (GO) enrichment and over-representation analyses using REACTOME and KEGG databases confirmed these similarities. In contrast, the direct comparison of WT and KO cells at the two stages showed fewer DEGs and overlaps in associated biological processes and signaling pathways. DEGs associated with the 3D stage, in which the phenotype manifests, contain DEGs and pathways that were predominantly linked to cell cycle linked processes, centromere assembly, or DNA replication. Furthermore, the transcription of genes encoding key junction proteins, additional polarity proteins, and cell-substrate interaction proteins is less affected by the loss of PALS1, indicating that PALS1 influences the transcriptional profiles in epithelial cells as a modulating factor. Show less

Cell polarity refers to the asymmetric distribution of biomacromolecules that enable the correct orientation of a cell in a particular direction. It is thus an essential component for appropriate tissue development and function. Viral infections can lead to dysregulation of polarity. This is associated with a poor prognosis due to viral interference with core cell polarity regulatory scaffolding proteins that often feature PDZ (PSD-95, DLG, and ZO-1) domains including Scrib, Dlg, Pals1, PatJ, Par3 and Par6. PDZ domains are also promiscuous, binding to several different partners through their C-terminal region which contain PDZ-binding motifs (PBM). Numerous viruses encode viral effector proteins that target cell polarity regulators for their benefit and include papillomaviruses, flaviviruses and coronaviruses. A better understanding of the mechanisms of action utilised by viral effector proteins to subvert host cell polarity sigalling will provide avenues for future therapeutic intervention, while at the same time enhance our understanding of cell polarity regulation and its role tissue homeostasis. Show less

Small structural E protein of coronaviruses uses its C-terminal PDZ motif to compromise the cellular PDZ interactome. In this work we compared core PDZ interactivity of small (seven amino acids) peptide PDZ motifs, originating from the envelope proteins of recently transmitted coronaviruses SARS-CoV, SARS-CoV2, and MERS-CoV. As the interaction targets we used 23 domains of the largest PDZ proteins MUPP1/MPDZ and PATJ/INAD. Results revealed exceptional affinity and interaction promiscuity of MERS-CoV PDZ motif in vitro, suggesting an increased probability of potential PDZ targets in vivo. We hypothesize that together with its known ability to enter the cells from both apical and basolateral sites, this might further contribute to its elevated disruption of cellular PDZ pathways and higher virulence. Show less

During the morula to blastocyst transformation, polarity establishment in outer cells is a prerequisite for trophectoderm lineage specification. This study reveals the roles of polarity proteins PATJ and MPDZ in trophectoderm lineage fate decision. In mouse preimplantation embryos, cell polarity plays a crucial role in the first lineage specification. PATJ and its homolog MPDZ are the main members of CRB-PALS1-PATJ (CRUMBS-Protein associated with Lin7 1-Pals-associated tight junction protein) apical polarity complex. They act as adaptor proteins connecting CRB-PALS1 and tight junction proteins, making them essential for cell polarization and stabilization of apical junctions. However, their roles in regulating trophectoderm differentiation and blastocyst development remain unclear. In this study, PATJ and/or MPDZ were downregulated by the microinjection of specific RNA interference constructs into zygotes. Downregulation of PATJ alone did not severely affect early embryonic development and trophectoderm lineage differentiation although it slowed down the blastocyst formation. Depletion of PATJ and MPDZ did not affect compaction and morula development but impaired blastocyst formation. Furthermore, the expression of trophectoderm-specific transcription factors and trophoblast differentiation was compromised in the absence of PATJ/MPDZ. These abnormalities might result from the breakdown of apical domain in the outer cells of the embryo. The loss of PATJ/MPDZ caused the breakdown of CRB and PAR polarity complexes as well as deficiencies in tight junctions and actin filaments. These defects led to ectopic activation of Hippo signaling in the outer cells of developing embryos, ultimately suppressing Cdx2 expression and trophectoderm differentiation. Altogether, PATJ and MPDZ are essential for trophectoderm lineage differentiation and normal blastocyst morphogenesis via the regulation of the establishment of apical domain, formation of tight junctions, phosphorylation and localization of YAP, and expression of trophectoderm-specific transcription factors. Show less

The conserved multiple PDZ-domain containing protein PATJ stabilizes the Crumbs-Pals1 complex to regulate apical-basal polarity and tight junction formation in epithelial cells. However, the molecular mechanism of PATJ's function in these processes is still unclear. In this study, we demonstrate that knockout of PATJ in epithelial cells results in tight junction defects as well as in a disturbed apical-basal polarity and impaired lumen formation in three-dimensional cyst assays. Mechanistically, we found PATJ to associate with and inhibit histone deacetylase 7 (HDAC7). Inhibition or downregulation of HDAC7 restores polarity and lumen formation. Gene expression analysis of PATJ-deficient cells revealed an impaired expression of genes involved in cell junction assembly and membrane organization, which is rescued by the downregulation of HDAC7. Notably, the function of PATJ regulating HDAC7-dependent cilia formation does not depend on its canonical interaction partner, Pals1, indicating a new role of PATJ, which is distinct from its function in the Crumbs complex. By contrast, polarity and lumen phenotypes observed in Pals1- and PATJ-deficient epithelial cells can be rescued by inhibition of HDAC7, suggesting that the main function of this polarity complex in this process is to modulate the transcriptional profile of epithelial cells by inhibiting HDAC7. Show less

Ufmylation is a recently identified small ubiquitin-like modification, whose biological function and relevant cellular targets are poorly understood. Here we present evidence of a neuroprotective role for Ufmylation involving Autophagy-related gene 9 (Atg9) during Drosophila aging. The Ufm1 system ensures the health of aged neurons via Atg9 by coordinating autophagy and mTORC1, and maintaining mitochondrial homeostasis and JNK (c-Jun N-terminal kinase) activity. Neuron-specific expression of Atg9 suppresses the age-associated movement defect and lethality caused by loss of Ufmylation. Furthermore, Atg9 is identified as a conserved target of Ufm1 conjugation mediated by Ddrgk1, a critical regulator of Ufmylation. Mammalian Ddrgk1 was shown to be indispensable for the stability of endogenous Atg9A protein in mouse embryonic fibroblast (MEF) cells. Taken together, our findings might have important implications for neurodegenerative diseases in mammals. Show less

Macroautophagy/autophagy is a cellular catabolic process that results in lysosome-mediated recycling of organelles and protein aggregates, as well as the destruction of intracellular pathogens. Its role in the maintenance of the intestinal epithelium is of particular interest, as several autophagy-related genes have been associated with intestinal disease. Autophagy and its regulatory mechanisms are involved in both homeostasis and repair of the intestine, supporting intestinal barrier function in response to cellular stress through tight junction regulation and protection from cell death. Furthermore, a clear role has emerged for autophagy not only in secretory cells but also in intestinal stem cells, where it affects their metabolism, as well as their proliferative and regenerative capacity. Here, we review the physiological role of autophagy in the context of intestinal epithelial maintenance and how genetic mutations affecting autophagy contribute to the development of intestinal disease. Show less

Epithelial tissues acquire their integrity and function through the apico-basal polarization of their constituent cells. Proteins of the PAR and Crumbs complexes are pivotal to epithelial polarization, but the mechanistic understanding of polarization is challenging to reach, largely because numerous potential interactions between these proteins and others have been found, without a clear hierarchy in importance. We identify the regionalized and segregated organization of members of the PAR and Crumbs complexes at epithelial apical junctions by imaging endogenous proteins using stimulated-emission-depletion microscopy on Caco-2 cells, and human and murine intestinal samples. Proteins organize in submicrometric clusters, with PAR3 overlapping with the tight junction (TJ) while PALS1-PATJ and aPKC-PAR6β form segregated clusters that are apical of the TJ and present in an alternated pattern related to actin organization. CRB3A is also apical of the TJ and partially overlaps with other polarity proteins. Of the numerous potential interactions identified between polarity proteins, only PALS1-PATJ and aPKC-PAR6β are spatially relevant in the junctional area of mature epithelial cells, simplifying our view of how polarity proteins could cooperate to drive and maintain cell polarity. Show less

Aqueous humor (AH) can be easily and safely used to evaluate disease-specific biomarkers in ocular disease. The aim of this study was to identify specific proteins biomarkers in the AH of retinoblastoma (RB) patients at various stages of the disease. We analyzed the proteome of 53 AH samples using high-resolution mass spectrometry. We grouped the samples according to active vitreous seeding (Group 1), active aqueous seeding (Group 2), naive RB (group 3), inactive RB (group 4), and congenital cataracts as the control (Group 5). We found a total of 889 proteins in all samples. Comparative parametric analyses among the different groups revealed three additional proteins expressed in the RB groups that were not expressed in the control group. These were histone H2B type 2-E (HISTH2B2E), InaD-like protein (PATJ), and ubiquitin conjugating enzyme E2 V1 (UBE2V1). Upon processing the data of our study with the OpenTarget Tool software, we found that glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and CD44 were more highly expressed in the RB groups. Our results provide a proteome database regarding AH related to RB disease that may be used as a source of biomarkers. Further prospective studies should validate our finding in a large cohort of RB patients. Show less

Women with extensive mammographic density (MD) are more likely to develop breast cancer than women with low MD because of a high epithelial component associated with a high proportion of stromal cells. To elucidate the biological association between high MD and risk of breast cancer, we compared the expression of a panel of genes coding for leptin, adiponectin, and some component of cell polarity and adherens junction complexes in dense and non-dense breast tissue. We interrogated a public dataset composed by 120 specimens of normal breast tissue with MD evaluation. The differential expression of the selected genes in the 2 MD subgroups was assessed by the Wilcoxon test, whereas Kruskal-Wallis test evaluated the differential expression of single genes in the fatty, epithelium, or nonfatty compartment. Spearman's correlation measured the relationship among genes in the subset with the highest epithelium proportion. In high MD, the expression level of PARD6B, CRB3, PATJ, LLGL2, CDH1, and MARVELD2 significantly lowered in tissues with the highest epithelium proportion, whereas, in low MD, the expression level of the genes increased with the increasing of the epithelium proportion. In the low MD subgroup, LEP correlated negatively with PRKCZ and DLG3, whereas, in high MD, such correlation was not observed. The expression of the genes governing cell polarity establishment and cell-cell adhesion assembly differed significantly in the epithelial component of dense and non-dense breasts. The correlation pattern between LEP and PRKCZ or DLG3 agrees with the role of leptin in cell polarity disruption. Show less