miR-10a Regulates Proliferation of Human Cardiomyocyte Progenitor Cells by Targeting GATA6

microRNAs (miRNAs) play essential roles in cardiogenesis. The altered expression of miRNAs can result in cardiac malformations by inducing abnormalities in the behavior of cardiac cells. However, the role of miR-10a in the regulation of cardiomyocyte progenitor cells (CMPCs) remains undetermined. In the present study, we found that up- or down-regulation of miR-10a inhibited or promoted the proliferation of human CMPCs, respectively, without affecting their differentiation toward cardiomyocytes. miR-10a bound to GATA6 directly and reduced GATA6 expression. Over-expression of GATA6 greatly attenuated the miR-10a-mediated inhibitory effect on the proliferation of human CMPCs. Thus, our results indicate that miR-10a could effectively modulate the proliferation of human CMPCs by targeting GATA6. The finding provides novel insights into the potency of miR-10a during heart development.     

Rab11b regulates the trafficking and recycling of the epithelial sodium channel (ENaC)

Expression of the epithelial sodium channel (ENaC) at the apical membrane of cortical collecting duct (CCD) principal cells is modulated by regulated trafficking mediated by vesicle insertion and retrieval. Small GTPases are known to facilitate vesicle trafficking, recycling, and membrane fusion events; however, little is known about the specific Rab family members that modify ENaC surface density. Using a mouse CCD cell line that endogenously expresses ENaC (mpkCCD), the channel was localized to both Rab11a- and Rab11b-positive endosomes by immunoisolation and confocal fluorescent microscopy. Expression of a dominant negative (DN) form of Rab11a or Rab11b significantly reduced the basal and cAMP-stimulated ENaC-dependent sodium (Na(+)) transport. The greatest reduction in Na(+) transport was observed with the expression of DN-Rab11b. Furthermore, small interfering RNA-mediated knockdown of each Rab11 isoform demonstrated the requirement for Rab11b in ENaC surface expression. These data indicate that Rab11b, and to a lesser extent Rab11a, is involved in establishing the constitutive and cAMP-stimulated Na(+) transport in mpkCCD cells.     

Cell death induced by Pteris semipinnata L. is associated with p53 and oxidant stress in gastric cancer cells

In this study, we demonstrated that Ent-11alpha-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F) had stronger cytotoxicity against MKN-45, a gastric cancer cell line bearing wild-type p53 than MKN-28, another gastric cancer cell line containing missense mutation in p53. The rapid increase of ROS level was involved in the mechanism of cytotoxicity. Classical features of apoptosis induced by 5F were observed in MKN-45 cells only or more significant in MKN-45 cells than MKN-28 cells. Translocation of Bax from cytosol to mitochondria, reduction of delta psi m and DNA fragmentation were induced by 5F in the p53-dependent manner. We conclude that the expression of Bax and its downstream molecules requires the presentation of a wild-type p53 in the cells treated by 5F.     

The inhibition of lung cancer cell growth by intracellular immunization with LC—1 ScFv

INTRODUCTIONLung cancer remains the leading cause of can-cer mortaIity in the world, accounting for more thanone sixth of cancer deaths in the world[1]. Antibod-ies have been proved to be a powerful tool fOr thestudy of 1ung cancer. A monoclonal IgM antibody,LC-1, was obtained in our laboratory. It can reactat a high rate with all four pathological types of lungcancers, including lung adenocarcinoma, 1ung squamous carcinoma, large cell lung cancer and smaIlcell lung cancert but not wit…     

Genetic differentiation and phylogeography of rotifer Polyarthra dolichoptera and P. vulgaris populations between Southeastern China and eastern North America: High intercontinental differences

Genetic differentiations and phylogeographical patterns of small organisms may be shaped by spatial isolation, environmental gradients, and gene flow. However, knowledge about genetic differentiation of rotifers at the intercontinental scale is still limited. Polyarthra dolichoptera and P. vulgaris are cosmopolitan rotifers that are tolerant to environmental changes, offering an excellent model to address the research gap. Here, we investigated the populations in Southeastern China and eastern North America and evaluated the phylogeographical patterns from their geographical range sizes, geographic–genetic distance relationships and their responses to spatial‐environmental factors. Using the mitochondrial cytochrome c oxidase subunit I gene as the DNA marker, we analyzed a total of 170 individuals. Our results showed that some putative cryptic species, also known as entities were widely distributed, but most of them were limited to single areas. The divergence of P. dolichoptera and P. vulgaris indicated that gene flow between continents was limited while that within each continent was stronger. Oceanographic barriers do affect the phylogeographic pattern of rotifers in continental waters and serve to maintain genetic diversity in nature. The genetic distance of P. dolichoptera and P. vulgaris populations showed significant positive correlation with geographic distance. This might be due to the combined effects of habitat heterogeneity, long‐distance colonization, and oceanographic barriers. Furthermore, at the intercontinental scale, spatial distance had a stronger influence than environmental variables on the genetic differentiations of both populations. Wind‐ and animal‐mediated transport and even historical events of continental plate tectonics are potential factors for phylogeography of cosmopolitan rotifers.