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1.
Vascular smooth muscle cells (VSMCs) are exposed to mechanical cyclic stretch in vivo, which play important roles in maintenance of vascular homeostasis and regulation of pathological vascular remodeling. Reversible protein phosphorylation is crucial for intracellular signaling transduction. However, the dynamic phosphorylated profile induced by cyclic stretch in VSMCs is still unclear. Using the stable isotope labeling by amino acid in cell culture, VSMCs were labeled and exposed to 10% physiological cyclic stretch in vitro at 1.25 Hz for 0 min, 15 min, 30 min, 1 h and 6 h, respectively. Using TiO2 beads and liquid chromatography tandem mass spectrometry, the temporal phosphoproteomic profiles in response to cyclic stretch were then detected. Bioinformatics analysis including fuzzy c-means clustering, functional classifications, and Ingenuity Pathway Analysis were applied to further reveal the potential mechanotranduction networks. The results indicated that protein kinase C (PKCs) family, Rho-associated coiled-coil containing protein kinase 1 (ROCK1) and Akt may participate in cyclic-stretch induced VSMC functions. Cyclic stretch repressed the expression of ROCK1, while it had no significant effect on the phosphorylation of PKCα/βII, PKCζ/λ and PKCδ/θ. PKCθ was activated first at short time-phase (15 min and 30 min), and again at long time-phase (6 h, 12 h and 24 h). The activation of p-PKCμ was immediate and short-term, similar to p-Akt. Our present in vitro work hence revealed that cyclic stretch activates complex mechanotransduction networks, suggesting that novel mechanoresponsive molecules, i.e., PKCθ, PKCμ, and ROCK1, may participate in the mechanotransduction and modulation VSMC functions.  相似文献   
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It is a long-standing question as to which genes define the characteristic facial features among different ethnic groups. In this study, we use Uyghurs, an ancient admixed population to query the genetic bases why Europeans and Han Chinese look different. Facial traits were analyzed based on high-dense 3D facial images; numerous biometric spaces were examined for divergent facial features between European and Han Chinese, ranging from inter-landmark distances to dense shape geometrics. Genome-wide association studies(GWAS) were conducted on a discovery panel of Uyghurs. Six significant loci were identified, four of which, rs1868752, rs118078182, rs60159418 at or near UBASH3B, COL23A1, PCDH7 and rs17868256 were replicated in independent cohorts of Uyghurs or Southern Han Chinese. A prospective model was also developed to predict 3D faces based on top GWAS signals and tested in hypothetic forensic scenarios.  相似文献   
3.
孢粉学是解决植物分类中疑难类群物种微形态分化的重要方法,随着分子系统学的发展,结合这两门学科的优势可以更加有效地解决疑难类群的分类学问题。鳞盖蕨属(Microlepia)是一个分类困难的疑难类群,采用孢粉学与分子系统学一一对应的方法,以及居群取样方式,选取280份样本,联合4个叶绿体片段(rbcL、trnL-F、psbA-trnH和rps4),采用最大似然法和贝叶斯法构建该属的系统发生关系,在此基础上对凭证标本中100份材料的孢子进行观察和分析。综合分子系统学和孢粉学的研究结果,得出结论:(1)在形态学研究中广泛被接受的15个物种得到了单系支持,并厘清了分类困难的复合群;(2)发现边缘鳞盖蕨(M. marginata)可能存在隐性种;(3)建议恢复过去归并处理为异名的瑶山鳞盖蕨(M. yaoshanica)、罗浮鳞盖蕨(M. lofoushanensis)、四川鳞盖蕨(M. szechuanica)以及滇西鳞盖蕨(M. subspeluncae);(4)提出鳞盖蕨属可能存在杂交现象;(5)提出鳞盖蕨属完整的属下分类建议。  相似文献   
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Septins are a highly conserved family of GTP‐binding proteins that contribute to many cellular and metabolic functions, including cell polarity, cytokinesis, cell morphogenesis and pathogenesis. In this study, we characterized the septins FaCdc3 and FaCdc12 in the filamentous fungus Fusarium asiaticum. The functions of FaCdc3 and FaCdc12 were evaluated by constructing deletion mutants of FaCdc3 and FaCdc12, designated ΔFaCdc3‐5 and ΔFaCdc12‐71, respectively. The deletion mutants exhibited a reduced rate of mycelial growth, increased aerial hyphae formation, irregularly shaped hyphae, reduced conidiation and a lack of sexual reproduction in wheat kernels. Histochemical analysis revealed that the conidia and hyphae of ΔFaCdc3‐5 and ΔFaCdc12‐71 formed large lipid droplets (LDs). ΔFaCdc3‐5 and ΔFaCdc12‐71 also exhibited increased resistance to agents that induce osmotic stress and damage the cell membrane and cell wall. In addition, the hyphae and conidia of the two mutants formed fewer septa than those of the wild‐type and exhibited aberrant nuclear distribution. Pathogenicity assays showed that ΔFaCdc3‐5 and ΔFaCdc12‐71 exhibited reduced virulence on wheat spikelets, which was indirectly correlated with a reduced level of deoxynivalenol accumulation. All of these defects were restored by genetic complementation of the two mutants with the parental FaCdc3 and FaCdc12. These results indicate that FaCdc3 and FaCdc12 play a critical role in various cellular processes in F. asiaticum.  相似文献   
6.
查阅保存于英国爱丁堡植物园标本馆(E)、华南植物园标本馆(IBSC)、邱园植物标本馆(K)、法国巴黎自然历史博物馆植物标本馆(P)和奥地利维也纳大学植物标本馆(WU)的荨麻科(Urticaceae)标本,发现在楼梯草属(Elatostema J.R.Forster & G.Forster)中有23种8变种的名称在原始描述中没有引证明确的标本,或引证有2份或2份以上的标本,但没指定模式.根据<国际植物命名法规>9.4、9.9和9.10,以及辅则9A.1、9A.2、9A.3和9A.4的精神,对这些名称做出后选模式指定.  相似文献   
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Mesenchymal stem cells (MSCs) are non-hematopoietic cells with multi-lineage potential, which makes them attractive targets for regenerative medicine applications. Efficient gene transfer into MSCs is essential for basic research in developmental biology and for therapeutic applications involving gene-modification in regenerative medicine. Adenovirus vectors (Advs) can efficiently and transiently introduce an exogenous gene into many cell types via their primary receptors, the coxsackievirus and adenovirus receptors (CARs), but not into MSCs, which lack CAR expression. To overcome this problem, an Adv coated with cationic polymer polyethyleneimine (PEI) was developed. In this study, we demonstrated that PEI coating with an optimal ratio can enhance adenoviral transduction of MSCs without cytotoxicity. We also investigated the physicochemical properties and internalization mechanisms of the PEI-coated Adv. These results could help to evaluate the potentiality of the PEI-coated Adv as a prototype vector for efficient and safe transduction into MSCs.  相似文献   
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A Gram-stain negative, motile, rod-shaped bacterium, designated strain WM-2T, was isolated from a forest soil in Sihui City, South China, and characterized by means of a polyphasic approach. Growth occurred with 0–5 % (w/v) NaCl (optimum 0–1 %) and at pH 5.0–10.5 (optimum pH 8.5) and 4–40 °C (optimum 30 °C) in Luria–Bertani medium. Comparative 16S rRNA gene sequence analyses showed that strain WM-2T is a member of the genus Pseudomonas and most closely related to P. guguanensis, P. oleovorans subsp. lubricantis, P. toyotomiensis, P. alcaliphila and P. mendocina with 97.1–96.6 % sequence similarities. In terms of gyrB and rpoB gene sequences, strain WM-2T showed the highest similarity with the type strains of the species P. toyotomiensis and P. alcaliphila. The DNA–DNA relatedness values of strain WM-2T with P. guguanensis and P. oleovorans subsp. lubricantis was 48.7 and 37.2 %, respectively. Chemotaxonomic characteristics (the main ubiquinone Q-9, major fatty acids C18:1 ω7c/C18:1 ω6c, C16:0 and C16:1 ω7c/C16:1 ω6c and DNA G+C content 65.2 ± 0.7 mol%) were similar to those of members of the genus Pseudomonas. Polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown aminophospholipid, an unknown phospholipid and five unknown lipids. According to the results of polyphasic analyses, strain WM-2T represents a novel species in the genus Pseudomonas, for which the name Pseudomonas sihuiensis sp. nov. is proposed. The type strain is WM-2T (=KCTC 32246T=CGMCC 1.12407T).  相似文献   
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