👤 Souichi Adachi

Hepatocellular carcinoma (HCC) arises from various etiologies, including viral hepatitis and non-viral liver diseases. Although comprehensive genomic profiling (CGP) is increasingly applied in oncology, the influence of disease etiology on the genomic landscape of HCC and biomarker applicability remains insufficiently characterized. CGP data from 551 patients with HCC, registered in the National Center for Cancer Genomics and Advanced Therapeutics (C-CAT) database, were analyzed after excluding cases with undefined etiology. We characterized the mutational landscape, compared mutation frequencies among HBV-, HCV-, and non-viral, non-cholestatic (nBnC)-related HCC, assessed the association between homologous recombination repair (HRR)-related gene alterations and tumor mutation burden (TMB), and evaluated the detection rates of actionable mutations in tissue- versus liquid-based CGP. Telomerase reverse transcriptase splice site mutations were the most common genomic alteration and were consistently observed across all etiologic groups. Although mutations in AXIN1 and DDR2 genes showed modest enrichment in HCV- and HBV-related HCC, respectively, the overall mutational profiles remained largely conserved across etiologies. TMB was significantly lower in nBnC-HCC compared to HCV-related HCC but showed no association with HRR-related mutations. The detection rates of targetable mutations were similar between tissue and liquid biopsies; however, only a small proportion of patients received matched therapies. Real-world data indicate a conserved genomic architecture in HCC regardless of etiology, supporting unified therapeutic approaches. The absence of a relationship between HRR alterations and TMB suggests distinct biological mechanisms. Liquid biopsy remains a reliable option when tissues are unavailable in managing patients with HCC. Show less

The transition from elementary to junior high school presents developmental challenges, particularly for students with neurodevelopmental traits. This study examined how autism, attention-deficit/hyperactivity disorder (ADHD) traits and effortful control (EC) were related to changes in mental health during this transition in a large Japanese community sample (N = 2,564). This longitudinal study used data from a community-based cohort of Japanese students and their parents/guardians (N = 2,692). Autism traits were measured using the Autism Spectrum Screening Questionnaire (ASSQ). ADHD traits were assessed with the Attention Deficit/Hyperactivity Disorder Rating Scale (ADHD-RS). Effortful control (EC) was evaluated using the "Effortful Control" subscale of the Early Adolescent Temperament Questionnaire-Revised (EATQ-R). Mental health problems were assessed using the Strengths and Difficulties Questionnaire (SDQ) before and after the transition. Generalized estimating equations (GEE) and latent profile analysis (LPA) were conducted to examine associations among autism and ADHD traits, EC, and mental health across the transition. GEE revealed that higher autism and ADHD traits and lower EC predicted more severe mental health problems. The LPA identified three distinct subgroups characterized by high, moderate, and low SDQ scores across the transition. The high-SDQ group showed elevated autism and ADHD traits and low EC, whereas the low-SDQ group showed low auism and ADHD traits and high EC. The moderate group exhibited intermediate levels for all measures. These findings suggest that pre-existing mental health problems tend to persist during the transition period. Importantly, students with higher autism and ADHD traits and lower EC exhibited diverse adaptation patterns-some improved while others worsened-highlighting that high autism traits are not necessarily associated with post-transition mental health deterioration. This underscores the need for support tailored to neurodevelopmental and self-regulatory profiles. Show less

Long-persistent luminescence (LPL) materials have applications from safety signage to bioimaging; however, existing organic LPL (OLPL) systems do not align with human scotopic vision, which is sensitive to blue light. We present a strategy to blueshift the emissions in binary OLPL systems by upconverting the charge-transfer (CT) to a locally excited (LE) singlet state. Through rigorous steady-state and time-resolved photoluminescence spectroscopy and wavelength-resolved thermoluminescence measurements, we provide the direct experimental evidence for this upconversion in OLPL systems featuring small energy offsets between the lowest-energy CT and LE singlet states. These systems exhibited strong room temperature LPL, particularly when extrinsic electron traps are added. Importantly, the developed OLPL system achieved Class A (ISO 17398) LPL, matching well with human scotopic vision. The findings not only elucidate the role of small energy offsets in modulating LPL but also provide potential avenues for enhancing the efficiency and applicability of OLPL materials. Show less

Lymphoplasmacytic lymphoma (LPL) is a type of low-grade B-cell lymphoma, with 90-95% of cases associated with Waldenström macroglobulinemia, characterized by the presence of IgM-type M-protein. We report, for the first time, a case of LPL-producing Bence Jones (BJ) protein kappa. The patient was a 78-year-old woman admitted to our department due to general fatigue and proteinuria that had persisted for 2 months. No M-protein was detected by blood immunofixation, but kappa-type BJ protein was detected in the urine. Light microscopy of a kidney biopsy sample revealed infiltration of lymphocytes and plasma cells into the perirenal adipose tissue and renal interstitium. The infiltrating cells exhibited kappa light chain restriction. Bone marrow examination revealed clusters of immature plasmacytoid lymphocytes that were CD20 positive, CD5 negative, and exhibited light chain restriction. Genetic analysis detected a MYD88 mutation, leading to the diagnosis of LPL in the patient. Six months after starting treatment with tirabrutinib, urinary protein levels improved to 0.2 g/gCr. Renal infiltration was identified due to urinary protein, and currently, no extramedullary lesions outside the kidneys are observed. Tirabrutinib has been extremely effective, but careful follow-up is still required. Show less

Targeting the drug tolerant persister (DTP) state in cancer cells should prevent further development of resistance mechanisms. This study explored combination therapies to inhibit alectinib-induced DTP cell formation from anaplastic lymphoma kinase-positive non-small cell lung cancer (ALK + NSCLC) patient-derived cells. After drug-screening 3114 compounds, pan-HER inhibitors (ErbB pathway) and tankyrase1/2 inhibitors (Wnt/β-catenin signaling) emerged as top candidates to inhibit alectinib-induced DTP cells growth. We confirmed knockdown of both TNKS1/2 in DTP cells recovered the sensitivity to alectinib. Further, our study suggested knockdown of TNKS1/2 increased stability of Axin1/2, which induced β-catenin degradation and decreased its nuclear translocation, thereby suppressing transcription of antiapoptotic and proliferation-related genes (survivin, c-MYC). Targeting both pathways with alectinib+pan-HER inhibitor and alectinib+TNKS1/2 inhibitor suppressed alectinib-induced DTP cells, and the triple combination almost completely prevented the appearance of DTP cells. In conclusion, combination with ALK-TKI, pan-HER and TNKS1/2 inhibitors has the potential to prevent the emergence of DTP in ALK + NSCLC. Show less

Endometriosis is a common condition associated with debilitating pelvic pain and infertility. A genome-wide association study meta-analysis, including 60,674 cases and 701,926 controls of European and East Asian descent, identified 42 genome-wide significant loci comprising 49 distinct association signals. Effect sizes were largest for stage 3/4 disease, driven by ovarian endometriosis. Identified signals explained up to 5.01% of disease variance and regulated expression or methylation of genes in endometrium and blood, many of which were associated with pain perception/maintenance (SRP14/BMF, GDAP1, MLLT10, BSN and NGF). We observed significant genetic correlations between endometriosis and 11 pain conditions, including migraine, back and multisite chronic pain (MCP), as well as inflammatory conditions, including asthma and osteoarthritis. Multitrait genetic analyses identified substantial sharing of variants associated with endometriosis and MCP/migraine. Targeted investigations of genetically regulated mechanisms shared between endometriosis and other pain conditions are needed to aid the development of new treatments and facilitate early symptomatic intervention. Show less

Oct4 collaborates primarily with other transcriptional factors or coregulators to maintain pluripotency. However, how Oct4 exerts its function is still unclear. Here, we show that the Oct4 linker interface mediates competing yet balanced Oct4 protein interactions that are crucial for maintaining pluripotency. Oct4 linker mutant embryonic stem cells (ESCs) show decreased expression of self-renewal genes and increased expression of differentiation genes, resulting in impaired ESC self-renewal and early embryonic development. The linker mutation interrupts the balanced Oct4 interactome. In mutant ESCs, the interaction between Oct4 and Klf5 is decreased. In contrast, interactions between Oct4 and Cbx1, Ctr9, and Cdc73 are increased, disrupting the epigenetic state of ESCs. Control of the expression level of Klf5, Cbx1, or Cdc73 rebalances the Oct4 interactome and rescues the pluripotency of linker mutant ESCs, indicating that such factors interact with Oct4 competitively. Thus, we provide previously unidentified molecular insights into how Oct4 maintains pluripotency. Show less

The aim of the present study was to consider whether the ultrastructural features of cardiomyocytes in dilated cardiomyopathy can be used to guide genetic testing. Endomyocardial biopsy and whole-exome sequencing were performed in 32 consecutive sporadic dilated cardiomyopathy patients [51.0 (40.0-64.0) years, 75% men] in initial phases of decompensated heart failure. The predicted pathogenicity of ultrarare (minor allele frequency ≤0.0005), non-synonymous variants was determined using the American College of Medical Genetics guidelines. Focusing on 75 cardiomyopathy-susceptibility and 41 arrhythmia-susceptibility genes, we identified 404 gene variants, of which 15 were considered pathogenic or likely pathogenic in 14 patients (44% of 32). There were five sarcomeric gene variants (29% of 17 variants) found in five patients (16% of 32), involving a variant of MYBPC3 and four variants of TTN. A patient with an MYBPC3 variant showed disorganized sarcomeres, three patients with TTN variants located in the region encoding the A-band domain showed sparse sarcomeres, and a patient with a TTN variant in encoding the I-band domain showed disrupted sarcomeres. The distribution of diffuse myofilament lysis depended on the causal genes; three patients with the same TMEM43 variant had diffuse myofilament lysis near nuclei (P = 0.011), while two patients with different DSP variants had lysis in the peripheral areas of cardiomyocytes (P = 0.033). Derangement patterns of myofilament and subcellular distribution of myofilament lysis might implicate causal genes. Large-scale studies are required to confirm whether these ultrastructural findings are related to the causative genes. Show less

17α, 20β-Dihydroxy-4-pregnen-3-one (DHP) is a maturation-inducing steroid in many teleost fish. Carbonyl reductase-like 20β-hydroxysteroid dehydrogenase (CR/20β-HSD) is a candidate enzyme responsible for DHP production during oocyte maturation in various fish, including Nile tilapia. However, a novel type of 17β-hydroxysteroid dehydrogenase, type 12-like (17β-HSD12L), is responsible for DHP production during oocyte maturation in masu salmon. 17β-HSD12 (presumably orthologous to salmon 17β-HSD12L) has been detected in Nile tilapia; however, its enzymatic activity and specific ability to convert the DHP substrate 17α-hydroxyprogesterone (17OHP) have not been examined. This study aimed to determine whether CR/20β-HSD or 17β-HSD12 is responsible for DHP production during oocyte maturation in the Nile tilapia. Mammalian expression vectors containing tilapia hsd17b12 or CR/20bhsd were transfected into HEK293T cells, followed by incubation with 17OHP. HEK293T cells transfected with hsd17b12 exhibited a strong ability to convert exogenous 17OHP to DHP (73.8% yield). Cells transfected with CR/20bhsd or the control vector converted only 7.4% and 7.5% of 17OHP to DHP, respectively. In addition, based on LC-MS/MS analyses, 17β-HSD12 did not convert any substrates other than 17OHP, including DHP, adrenosterone, androstenedione, estrone, testosterone, 11-ketotestosterone, and estradiol-17β. CR/20β-HSD showed strong 17β-HSD oxidoreductase activity especially with adrenosterone and androstenedione. Tissue-specific hsd17b12 expression analyzed by RT-PCR showed that hsd17b12 mRNA was strongest amplification in full-grown follicles. Finally, full-grown ovarian follicles were incubated with salmon pituitary extract (SPE, 100 µg/mL) or human chorionic gonadotropin (HCG, 100 IU/mL) to induce 20β-HSD activity in vitro, and enzyme activity was assessed by co-incubation with 100 ng/mL 17OHP for 2, 4, 8, and 16 h. Conversion of 17OHP to DHP by ovarian follicles incubated with SPE and HCG peaked at 16 h, subsequent with increased follicular hsd17b12 mRNA levels, which were significantly higher than those in control incubations. However, the levels of CR/20bhsd mRNA remained low and did not differ among time points. The present study strongly suggests that 17β-HSD12, and not CR/20β-HSD, is the 20β-HSD responsible for DHP production by ovarian follicles during oocyte maturation in Nile tilapia. Show less

Mixed-lineage leukemia (MLL) gene rearrangements are among the most frequent chromosomal abnormalities in acute myeloid leukemia (AML). MLL fusion patterns are associated with the patient's prognosis; however, their relationship with driver mutations is unclear. We conducted sequence analyses of 338 genes in pediatric patients with MLL-rearranged (MLL-r) AML (n = 56; JPLSG AML-05 study) alongside data from the TARGET study's pediatric cohorts with MLL-r AML (n = 104), non-MLL-r AML (n = 581), and adult MLL-r AML (n = 81). KRAS mutations were most frequent in pediatric patients with high-risk MLL fusions (MLL-MLLLT10, MLL-MLLT4, and MLL-MLLT1). Pediatric patients with MLL-r AML (n = 160) and a KRAS mutation (KRAS-MT) had a significantly worse prognosis than those without a KRAS mutation (KRAS-WT) (5-year event-free survival [EFS]: 51.8% vs 18.3%, P < .0001; 5-year overall survival [OS]: 67.3% vs 44.3%, P = .003). The adverse prognostic impact of KRAS mutations was confirmed in adult MLL-r AML. KRAS mutations were associated with adverse prognoses in pediatric patients with both high-risk (MLLT10+MLLT4+MLLT1; n = 60) and intermediate-to-low-risk (MLLT3+ELL+others; n = 100) MLL fusions. The prognosis did not differ significantly between patients with non-MLL-r AML with KRAS-WT or KRAS-MT. Multivariate analysis showed the presence of a KRAS mutation to be an independent prognostic factor for EFS (hazard ratio [HR], 2.21; 95% confidence interval [CI], 1.35-3.59; P = .002) and OS (HR, 1.85; 95% CI, 1.01-3.31; P = .045) in MLL-r AML. The mutation is a distinct adverse prognostic factor in MLL-r AML, regardless of risk subgroup, and is potentially useful for accurate treatment stratification. This trial was registered at the UMIN (University Hospital Medical Information Network) Clinical Trials Registry (UMIN-CTR; http://www.umin.ac.jp/ctr/index.htm) as #UMIN000000511. Show less

To assess the use of plasma free amino acids (PFAAs) as biomarkers for metabolic disorders, it is essential to identify genetic factors that influence PFAA concentrations. PFAA concentrations were absolutely quantified by liquid chromatography-mass spectrometry using plasma samples from 1338 Japanese individuals, and genome-wide quantitative trait locus (QTL) analysis was performed for the concentrations of 21 PFAAs. We next conducted a conditional QTL analysis using the concentration of each PFAA adjusted by the other 20 PFAAs as covariates to elucidate genetic determinants that influence PFAA concentrations. We identified eight genes that showed a significant association with PFAA concentrations, of which two, SLC7A2 and PKD1L2, were identified. SLC7A2 was associated with the plasma levels of arginine and ornithine, and PKD1L2 with the level of glycine. The significant associations of these two genes were revealed in the conditional QTL analysis, but a significant association between serine and the CPS1 gene disappeared when glycine was used as a covariate. We demonstrated that conditional QTL analysis is useful for determining the metabolic pathways predominantly used for PFAA metabolism. Our findings will help elucidate the physiological roles of genetic components that control the metabolism of amino acids. Show less

Recent advances in the genetic understanding of acute myeloid leukemia (AML) have improved clinical outcomes in pediatric patients. However, ∼40% of patients with pediatric AML relapse, resulting in a relatively low overall survival rate of ∼70%. The objective of this study was to reveal the comprehensive genetic background of pediatric AML. We performed transcriptome analysis (RNA sequencing [RNA-seq]) in 139 of the 369 patients with de novo pediatric AML who were enrolled in the Japanese Pediatric Leukemia/Lymphoma Study Group AML-05 trial and investigated correlations between genetic aberrations and clinical information. Using RNA-seq, we identified 54 in-frame gene fusions and 1 RUNX1 out-of-frame fusion in 53 of 139 patients. Moreover, we found at least 258 gene fusions in 369 patients (70%) through reverse transcription polymerase chain reaction and RNA-seq. Five gene rearrangements were newly identified, namely, NPM1-CCDC28A, TRIP12-NPM1, MLLT10-DNAJC1, TBL1XR1-RARB, and RUNX1-FNBP1. In addition, we found rare gene rearrangements, namely, MYB-GATA1, NPM1-MLF1, ETV6-NCOA2, ETV6-MECOM, ETV6-CTNNB1, RUNX1-PRDM16, RUNX1-CBFA2T2, and RUNX1-CBFA2T3. Among the remaining 111 patients, KMT2A-PTD, biallelic CEBPA, and NPM1 gene mutations were found in 11, 23, and 17 patients, respectively. These mutations were completely mutually exclusive with any gene fusions. RNA-seq unmasked the complexity of gene rearrangements and mutations in pediatric AML. We identified potentially disease-causing alterations in nearly all patients with AML, including novel gene fusions. Our results indicated that a subset of patients with pediatric AML represent a distinct entity that may be discriminated from their adult counterparts. Based on these results, risk stratification should be reconsidered. Show less

To explore possible roles of heparanase in cancer-host crosstalk, we examined whether heparanase influences expression of inflammatory chemokines in colorectal cancer cells. Murine colorectal carcinoma cells incubated with heparanase upregulated MCP-1, KC, and RANTES genes and released MCP-1 and KC proteins. Heparanase-dependent production of IL-8 was detected in two human colorectal carcinoma cell lines. Addition of a heparanase inhibitor Heparastatin (SF4) did not influence MCP-1 production, while both latent and mature forms of heparanase augmented MCP-1 release, suggesting that heparanase catalytic activity was dispensable for MCP-1 production. In contrast, addition of heparin to the medium suppressed MCP-1 release in a dose-dependent manner. Similarly, targeted suppression of Ext1 by RNAi significantly suppressed cell surface expression of heparan sulfate and MCP-1 production in colon 26 cells. Taken together, it is concluded that colon 26 cells transduce the heparanase-mediated signal through heparan sulfate binding. We propose a novel function for heparanase independent of its endoglycosidase activity, namely as a stimulant for chemokine production. Show less

Transient abnormal myelopoiesis (TAM) is a myeloid proliferation resembling acute megakaryoblastic leukemia (AMKL), mostly affecting perinatal infants with Down syndrome. Although self-limiting in a majority of cases, TAM may evolve as non-self-limiting AMKL after spontaneous remission (DS-AMKL). Pathogenesis of these Down syndrome-related myeloid disorders is poorly understood, except for GATA1 mutations found in most cases. Here we report genomic profiling of 41 TAM, 49 DS-AMKL and 19 non-DS-AMKL samples, including whole-genome and/or whole-exome sequencing of 15 TAM and 14 DS-AMKL samples. TAM appears to be caused by a single GATA1 mutation and constitutive trisomy 21. Subsequent AMKL evolves from a pre-existing TAM clone through the acquisition of additional mutations, with major mutational targets including multiple cohesin components (53%), CTCF (20%), and EZH2, KANSL1 and other epigenetic regulators (45%), as well as common signaling pathways, such as the JAK family kinases, MPL, SH2B3 (LNK) and multiple RAS pathway genes (47%). Show less

Human ATP-binding cassette (ABC) transporter ABCC2 (cMOAT/MRP2) plays a crucial role in the hepatobiliary transport of sulfate-, glucuronide-, and glutathione-conjugated metabolites as well as a variety of amphiphilic organic anions derived from hepatic metabolism. Molecular mechanisms underlying the induction of this hepatic ABC transporter are of great interest to understand the transport-metabolism interplay in vivo. In the present study, to gain insight into the mechanism of ABCC2 induction, we tested a total of 46 structurally diverse compounds, including nuclear receptor ligands, antibiotics, bile salts, phytochemicals, and anticancer drugs. Among them, we found that LXRalpha ligands, i.e., T0901317, paxilline, and 22(R)-hydroxycholesterol, acted potently to induce the expression of ABCC2 at both mRNA and protein levels in human hepatocellular carcinoma HepG2 cells. The ABCC2 induction by T0901317 was dose- and time-dependent, where the induction pattern of ABCC2 was very similar to that of ABCG1, one of the target genes of LXRalpha. The ABCC2 induction by T0901317 was more strongly elicited when the LXRalpha gene was transiently transfected into HepG2 cells. In contrast, ABCC2 induction by T0901317 was attenuated by transient transfection of a dominant negative LXRalpha variant, suggesting that LXRalpha is involved in ABCC2 induction. Interestingly, RXR, a heterodimer partner of LXRalpha, affected the mRNA levels of ABCC2 and ABCG1 differently. ABCC2 induction by T0901317 was enhanced by RXR siRNA treatment, whereas ABCG1 induction was suppressed by the same treatment. This is the first report demonstrating that LXRalpha is potentially involved in ABCC2 induction. Show less

MUPP1 and Patj are both composed of an L27 domain and multiple PDZ domains (13 and 10 domains, respectively) and are localized to tight junctions (TJs) in epithelial cells. Although Patj is known to be responsible for the organization of TJs and epithelial polarity, characterization of MUPP1 is lacking. In this study, we found that MUPP1 and Patj share several binding partners, including JAM1, ZO-3, Pals1, Par6, and nectins (cell-cell adhesion molecules at adherens junctions). MUPP1 and Patj exhibited similar subcellular distributions, and the mechanisms with which they localize to TJs also appear to overlap. Despite these similarities, functional studies have revealed that Patj is indispensable for the establishment of TJs and epithelial polarization, whereas MUPP1 is not. Thus, although MUPP1 and Patj share several molecular properties, their functions are entirely different. We present evidence that the signaling mediated by Pals1, which has a higher affinity for Patj than for MUPP1 and is involved in the activation of the Par6-aPKC complex, is of principal importance for the function of Patj in epithelial cells. Show less

Apolipoprotein (apo) A-V has been the focus of significant attention as a potential modulator of plasma triglyceride (TG) in spite of its very low plasma concentration. TG levels are frequently elevated in patients with end-stage renal disease (ESRD), which is associated with a high prevalence of cardiovascular disease among them. We measured plasma apo A-V levels in 20 control subjects and 70 patients with diabetic and nondiabetic ESRD to investigate whether low apo A-V levels could be involved in the pathogenesis of the hyper-TG in ESRD. The plasma TG levels were significantly elevated in diabetic patients with ESRD, whereas those in nondiabetic ESRD patients remained similar to those in the controls. High-density lipoprotein cholesterol levels were significantly lower in the patients with ESRD than in the controls, irrespective of the presence of diabetes. Apo A-V levels measured by an enzyme-linked immunosorbent assay were markedly reduced to 40% to 44% of the control levels in both diabetic and nondiabetic patients with ESRD. The apo A-V levels were not correlated with TG in the overall study population, but they were positively correlated with high-density lipoprotein cholesterol. These results suggest that reduced apo A-V levels do not necessarily lead to hyper-TG in ESRD, but we are unable to exclude the possibility that low apo A-V plays a role in raising the TG level in diabetic ESRD. Show less

Carbamoylphosphate synthetase I deficiency (CPS1D) is a urea-cycle disorder characterized by episodes of life-threatening hyperammonemia. Correct diagnosis is crucial for patient management, but is difficult to make from clinical presentation and conventional laboratory tests alone. Enzymatic or genetic diagnoses have also been hampered by difficult access to the appropriate organ and the large size of the gene (38 exons). In this study, in order to address this diagnostic dilemma, we performed the largest mutational and clinical analyses of this disorder to date in Japan. Mutations in CPS1 were identified in 16 of 18 patients with a clinical diagnosis of CPS1D. In total, 25 different mutations were identified, of which 19 were novel. Interestingly, in contrast to previous reports suggesting an extremely diverse mutational spectrum, 31.8% of the mutations identified in Japanese were common to more than one family. We also identified two common polymorphisms that might be useful for simple linkage analysis in prenatal diagnosis. The accumulated clinical data will also help to reveal the clinical presentation of this rare disorder in Japan. Show less

We have previously shown that MUPP1, which has an MRE domain and 13 PDZ domains, is expressed in epithelial cells and localize at tight junctions (TJs) and apical membranes. Using yeast two-hybrid screening, we found here that MUPP1 interacts with angiomotin (Amot), JEAP/Amot-like 1 and MASCOT/Amot-like 2, which we refer to as Amot/JEAP family proteins. PDZ2 and -3 were responsible for MUPP1's interaction with Amot and MASCOT, whereas only PDZ3 was responsible for its interaction with JEAP. All the Amot/JEAP family proteins also interacted with Patj, a close relative of MUPP1. The C-terminal PDZ-binding motives of the Amot/JEAP family were required for these interactions. We successfully generated specific antibodies for these proteins and analyzed the endogenous molecular properties of the family in parallel. Immunofluorescence microscopy of cultured epithelial cells showed that in subcellular distribution, the Amot/JEAP family proteins were indistinguishable; they were apparent at TJs as well as apical membranes, and mostly co-localized with MUPP1. They were also located at TJs in several mouse tissues, but each protein showed a distinct tissue distribution. In biochemical fractionation assays, the Amot/JEAP family behaved not as transmembrane but as peripheral membrane proteins. Unexpectedly, the PDZ-binding motives were not necessarily required for their localization to TJs, and dominant negative MUPP1 or Patj did not affect the localization of Amot/JEAP family proteins, suggesting that the interaction with MUPP1/Patj is not necessarily responsible for their proper subcellular distribution. Show less

Mitogen-activated protein kinases (MAPKs) are specifically phosphorylated and activated by the MAPK kinases, phosphorylate various targets such as MAPK-activated protein kinases and transcription factors, and are inactivated by specific phosphatases. Recently, docking interactions via the non-catalytic regions of MAPKs have been suggested to be important in regulating these reactions. Here we identify docking sites in MAPKs and in MAPK-interacting enzymes. A docking domain in extracellular-signal-regulated kinase (ERK), a MAPK, serves as a common site for binding to the MAPK kinase MEK1, the MAPK-activated protein kinase MNK1 and the MAPK phosphatase MKP3. Two aspartic acids in this domain are essential for docking, one of which is mutated in the sevenmaker mutant of Drosophila ERK/Rolled. A corresponding domain in the MAPKs p38 and JNK/SAPK also serves as a common docking site for their MEKs, MAPK-activated protein kinases and MKPs. These docking interactions increase the efficiency of the enzymatic reactions. These findings reveal a hitherto unidentified docking motif in MAPKs that is used in common for recognition of their activators, substrates and regulators. Show less

Human apolipoprotein A-IV (apoA-IV) is genetically polymorphic, the apoA-IV polymorphism being controlled by two alleles, apoA-IV1 and apoA-IV2. The association between the apoA-IV2 allele and late-onset Alzheimer's disease (LOAD) has been reported in Caucasian populations. We investigated the codon 360 mutation of the apoA-IV gene allele frequency in 173 LOAD and in 158 age-matched control subjects of the Japanese population, and we found that the allele frequency of apoA-IV2 in the Japanese population was very rare and was extremely lower than in Caucasian populations. We conclude that there was no association between apoA-IV genotype and LOAD in the Japanese population. Copyrightz1999S.KargerAG,Basel Show less