👤 Paweł Pomorski

DOCK7 (dedicator of cytokinesis 7) is a guanidine nucleotide exchange factor (GEF) for Rac1 GTPase that is involved in neuronal polarity and axon generation as well in Schwann cell differentiation and myelination. Recently, we identified DOCK7 as the binding partner of unconventional myosin VI (MVI) in neuronal-lineage PC12 cells and postulated that this interaction could be important in vivo [Majewski et al. (2012) Biochem Cell Biol., 90:565-574]. Herein, we found that MVI-DOCK7 interaction takes also place in other cell lines and demonstrated that MVI cargo domain via its RRL motif binds to DOCK7 C-terminal M2 and DHR2 domains. In MVI knockdown cells, lower Rac1 activity and a decrease of DOCK7 phosphorylation on Tyr1118 were observed, indicating that MVI could contribute to DOCK7 activity. MVI and DOCK7 co-localization was maintained during NGF-stimulated PC12 cell differentiation and observed also in the outgrowths. Also, during differentiation an increase in phosphorylation of DOCK7 as well as of its downstream effector JNK kinase was detected. Interestingly, overexpression of GFP-tagged MVI cargo domain (GFP-GT) impaired protrusion formation indicating that full length protein is important for this process. Moreover, a transient increase in Rac activity observed at 5min of NGF-stimulated differentiation of PC12 cells (overexpressing either GFP or GFP-MVI) was not detected in cells overexpressing the cargo domain. These data indicate that MVI-DOCK7 interaction could have functional implications in the protrusion outgrowth, and full length MVI seems to be important for delivery and maintenance of DOCK7 along the protrusions, and exerting its GEF activity. Show less

The aim of the study was to estimate both active and passive pregnant women exposure to tobacco smoke. 154 women hospitalized at the Gynaecology and Obstetrics Department in Opole, Poland and at the Gynaecology and Obstetrics Department of Hospital Universitario Monterey in Mexico have undergone the examination. The patients have been surveyed in order to obtain a subjective evaluation of their exposure. Then the exhaled carbon monoxide (ExhCO) measurement used for objective monitoring tobacco smoking has been performed. According to the results of the questionnaire 40 women (26% of the examined patients) confirmed smoking in pregnancy. 24 women (60% of smoking ones) have been smoking for the whole period of pregnancy. Though the rate of smoking among Polish and Mexican women was comparable, Polish mothers were less likely to quit after confirmation of pregnancy. Both Polish and Mexican smoking mothers were much younger than their non-smoking counterparts. The babies of the smoking mothers have been noticed to obtain the lower count in Apgar scale. The exhaled carbon monoxide (ExhCO) measurement has revealed that 14 Polish and 10 Mexican patients have been exposed to tobacco smoke. The results of their questionnaires have been thoroughly examined. 71% of them confirmed active smoking in pregnancy, 8.3% pointed to second-hand smoke exposure, 20.7% lied by denying the exposure. Thus the need to verify the questionnaires results has been confirmed. The mean value of ExhCO of both non-smoking women and those, who quit smoking after confirmation of pregnancy was equal. This may suggest that quitting smoking in the early stages of pregnancy reduce the risk of the harmful smoke impact on the unborn baby. Nearly doubled average concentration of ExhCO among passive smoking mothers in comparison to the non-smoking ones arises a serious concern. Show less

According to the current data over 12 million Polish citizens smoke tobacco, 40% of them are women. Maternal smoking in pregnancy significantly increases the rate of having a low-birthweight baby, the rate of perinatal mortality and several other adverse pregnancy outcomes. The aim of the study was to estimate the rate of smoking women during pregnancy and those who are exposed to secondhand smoke. 219 women hospitalized at Gynecology and Obstetrics Department of Wroclaw Medical University and Gynecology and Obstetrics Department in Opole have undergone the examination. The pregnant women have been interviewed and the results of questionnaire have been checked by the exhaled carbon monoxide (ExhCO) measurement. CO expresses the percentage of carboxyhemoglobin (HbCO) and is used for objective monitoring tobacco smoking. The results of the study suggest that regular exposure to secondhand smoke becomes a serious problem. 25.5% patients from Wrocław and 16.4% patients from Opole have declared passive smoking. The mean value of ExhCO in this group of women obtained the level of 3.3 ppm vs 1.95 ppm in the group of patients who have denied both active and passive exposure. Show less