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Nanociliates have been frequently found to be important players in the marine microbial loop, however, little is known about their diversity and distribution in coastal ecosystems. We investigated the molecular diversity and distribution patterns of nanoplanktonic oligotrich and choreotrich (OC) ciliates in surface water of three neritic basins of northern China, the South Yellow Sea (SYS), North Yellow Sea (NYS), and Bohai Sea (BS) in June and November 2011. SSU rRNA gene clone libraries generated from three summertime samples (sites B38, B4 and H8) were analyzed and revealed a large novel ribotype diversity, of which many were low-abundant phylotypes belonging to the subclass Oligotrichia, but divergent from described morphospecies. Based on the data of terminal-restriction fragment length polymorphism (T-RFLP) analysis of all 35 samples, we found that the T-RF richness was generally higher in the SYS than in the BS, and negatively correlated with the molar ratio of P to Si. Overall, multidimensional scaling and permutational multivariate analysis of variance of the community turnover demonstrated a distinct seasonal pattern but no basin-to-basin differentiation across all samples. Nevertheless, significant community differences among basins were recognized in the winter dataset. Mantel tests showed that the environmental factors, P:Si ratio, water temperature and concentration of dissolved oxygen (DO), determined the community across all samples. However, both biogeographic distance and environment shaped the community in winter, with DO being the most important physicochemical factor. Our results indicate that the stoichiometric ratio of P:Si is a key factor, through which the phytoplankton community may be shaped, resulting in a cascade effect on the diversity and community composition of OC nanociliates in the N-rich, Si-limited coastal surface waters, and that the Yellow Sea Warm Current drives the nanociliate community, and possibly the microbial food webs, in the coastal ecosystem in winter. [ABSTRACT FROM AUTHOR]

Though the Y-chromosome O2a-M95 lineage is one of the major haplogroups present in eastern Asian populations, especially among Austro-Asiatic speaking populations from Southwestern China and mainland Southeast Asia, to date its phylogeny lacks structure due to only one downstream SNP marker (M88) assigned to the lineage. A recent array-capture-based Y chromosome sequencing of Asian samples has yielded a variety of novel SNPs purportedly belonging to the O2a-M95 lineage, but their phylogenetic positions have yet to be determined. In this study, we sampled 646 unrelated males from 22 Austro-Asiatic speaking populations from Cambodia, Thailand and Southwestern China, and genotyped 12 SNP makers among the sampled populations, including 10 of the newly reported markers. Among the 646 males, 343 belonged to the O2a-M95 lineage, confirming the supposed dominance of this Y chromosome lineage in Austro-Asiatic speaking populations. We further characterized the phylogeny of O2a-M95 by defining 5 sub-branches: O2a1*-M95, O2a1a-F789, O2a1b*-F1252, O2a1b1*-M88 and O2a1b1a -F761. This updated phylogeny not only improves the resolution of this lineage, but also allows for greater tracing of the prehistory of human populations in eastern Asia and the Pacific, which may yield novel insights into the patterns of language diversification and population movement in these regions. [ABSTRACT FROM AUTHOR]

Aims: Deubiquitinating enzymes (DUBs) appear to be critical regulators of a multitude of processes such as proliferation, apoptosis, differentiation, and inflammation; however, the potential roles of DUBs in the heart remain to be determined. This study was aimed to explore the role of a DUB, ubiquitin carboxyl terminal hydrolyase L1 (UCH-L1) in maladaptive cardiac remodeling and dysfunction. Methods and Results: Maladaptive cardiac remodeling and dysfunction were induced in mice by transverse aortic constriction (TAC). UCH-L1 expression was transiently increased and then declined near to the basal level while impairment of cardiac function proceeded. The upregulation of UCH-L1 was observed in cardiac myocytes and fibroblasts. In primary culture of cardiac fibroblasts, UCH-L1 was upregulated by platelet-derived growth factor (PDGF)-BB and PDGF-DD. Adenoviral overexpession of UCH-L1 inhibited the PDGF-induced cardiac fibroblast proliferation without affecting the activation of mitogen activated protein kinases (MAPKs), Akt, and signal transducers and activators of transcription 3 (STAT3). Further signaling dissection revealed that PDGF-BB posttranscriptional upregulated p21WAF1/Cip1 protein expression, which was inhibited by rapamycin, an activator of autophagy via suppressing mammalian target of rapamycin (mTOR), rather than MG132, a proteasome inhibitor. Overexpression of UCH-L1 enhanced PDGF-BB-induced mTOR phosphorylation and upregulation of p21WAF1/Cip1 protein expression while suppressed autophagic flux in cardiac fibroblasts. Conclusion: UCH-L1 facilitates PDGF-BB-induced suppression of autophagic degradation of p21WAF1/Cip1 proteins in cardiac fibroblasts, which may serve as a novel negative feedback mechanism in the control of cardiac fibroblast proliferation contributing to cardiac fibrosis and dysfunction. [ABSTRACT FROM AUTHOR]

The Y-chromosome haplogroup N-M231 (Hg N) is distributed widely in eastern and central Asia, Siberia, as well as in eastern and northern Europe. Previous studies suggested a counterclockwise prehistoric migration of Hg N from eastern Asia to eastern and northern Europe. However, the root of this Y chromosome lineage and its detailed dispersal pattern across eastern Asia are still unclear. We analyzed haplogroup profiles and phylogeographic patterns of 1,570 Hg N individuals from 20,826 males in 359 populations across Eurasia. We first genotyped 6,371 males from 169 populations in China and Cambodia, and generated data of 360 Hg N individuals, and then combined published data on 1,210 Hg N individuals from Japanese, Southeast Asian, Siberian, European and Central Asian populations. The results showed that the sub-haplogroups of Hg N have a distinct geographical distribution. The highest Y-STR diversity of the ancestral Hg N sub-haplogroups was observed in the southern part of mainland East Asia, and further phylogeographic analyses supports an origin of Hg N in southern China. Combined with previous data, we propose that the early northward dispersal of Hg N started from southern China about 21 thousand years ago (kya), expanding into northern China 12–18 kya, and reaching further north to Siberia about 12–14 kya before a population expansion and westward migration into Central Asia and eastern/northern Europe around 8.0–10.0 kya. This northward migration of Hg N likewise coincides with retreating ice sheets after the Last Glacial Maximum (22–18 kya) in mainland East Asia. [ABSTRACT FROM AUTHOR]