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201.
202.
Diwen Liang George B. McManus Qing Wang Xian Sun Zhiwei Liu Senjie Lin Yufeng Yang 《Ecology and evolution》2022,12(5)
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. 相似文献
203.
204.
Soomin Lee Zheng Li Dehua Meng Qinming Fei Libo Jiang Tengfei Fu Ze Wang Shuhao Liu Jian Zhang 《Acta biochimica et biophysica Sinica》2021,(11):1516-1526
Vascularization is an important early indicator of osteogenesis involving biomaterials.Bone repair and new bone formation are associated with extensive neovascu... 相似文献
205.
转基因红花中角质细胞生长因子KGF-1的表达 总被引:3,自引:0,他引:3
通过构建重组表达质粒载体p139035S-KGF1和根癌农杆菌介导在红花(Carthamus tinctorius)中表达角质细胞生长因子(KGF-1)。从侵染到诱导生根共需要14周, 转化率达0.1%。红花子叶在潮霉素筛选培养基上培养4–5周后便可获得丛生芽, 再生芽移入含潮霉素的伸长生根培养基, 培养4–8周可诱导生根。通过PCR、Southern blot、RT-PCR及Western blot检测证明目的基因KGF-1已经整合到红花细胞的染色体中, 实现了KGF-1外源蛋白在红花中的成功表达, 为开发KGF-1蛋白新的生产途径奠定了基础。 相似文献
206.
Shenghe Huang Ruijie Liu Yiding Niu Agula Hasi 《Russian Journal of Plant Physiology》2010,57(4):568-573
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209.
Zhang?Lijuan Jifu?Liu Hao?Zhang Shanshan?Wu Lingyun?Huang Dacheng?He Xueyuan?XiaoEmail author 《中国科学C辑(英文版)》2005,48(6):641-647
There are multiple reports of autoimmune response in patients with lung cancer. To investigate whether a novel autoantibody
is present in patients with lung cancer and evaluate its clinical diagnostic and prognostic value, sera from 10 patients with
lung cancer and 10 normal individuals were analyzed using immunofluorescence and Western blotting. It was found that one serum
sample from the patients with squamous carcinoma gave a fine speckled pattern staining in nucleus and had a high titer antinuclear
autoantibody which could recognize 31 kD of nuclear protein isolated from both cancer cells and normal cells. The same patient’s
serum was further used to immunoprecipitate the target antigen. The protein bands were excised from the SDS-PAGE gels and
were analyzed with a Qstar Pulser I Quadrupole time-flight mass spectrometer, and the 31 kD target antigen was identified
as U1-AsnRNP. To test the prevalence of anti-U1-AsnRNP antibody, sera from 93 patients including 36 squmaous carcinomas (SCC),
26 adenocarcinomas (Ad), and 31 small cell carcinomas (SCLC) were screened by Western blotting. The results demonstrated that
anti-U1-A snRNP antibody was present in 50% of SCC sera, 26.9% of Ad sera and 54.8% of SCLC sera. In this paper, we report
for the first time that anti-U1-AsnRNP antibody could be detected in the patients with lung cancer. 相似文献
210.
Natasha Wood Tanmoy Bhattacharya Brandon F. Keele Elena Giorgi Michael Liu Brian Gaschen Marcus Daniels Guido Ferrari Barton F. Haynes Andrew McMichael George M. Shaw Beatrice H. Hahn Bette Korber Cathal Seoighe 《PLoS pathogens》2009,5(5)
The pattern of viral diversification in newly infected individuals provides information about the host environment and immune responses typically experienced by the newly transmitted virus. For example, sites that tend to evolve rapidly across multiple early-infection patients could be involved in enabling escape from common early immune responses, could represent adaptation for rapid growth in a newly infected host, or could represent reversion from less fit forms of the virus that were selected for immune escape in previous hosts. Here we investigated the diversification of HIV-1 env coding sequences in 81 very early B subtype infections previously shown to have resulted from transmission or expansion of single viruses (n = 78) or two closely related viruses (n = 3). In these cases, the sequence of the infecting virus can be estimated accurately, enabling inference of both the direction of substitutions as well as distinction between insertion and deletion events. By integrating information across multiple acutely infected hosts, we find evidence of adaptive evolution of HIV-1 env and identify a subset of codon sites that diversified more rapidly than can be explained by a model of neutral evolution. Of 24 such rapidly diversifying sites, 14 were either i) clustered and embedded in CTL epitopes that were verified experimentally or predicted based on the individual''s HLA or ii) in a nucleotide context indicative of APOBEC-mediated G-to-A substitutions, despite having excluded heavily hypermutated sequences prior to the analysis. In several cases, a rapidly evolving site was embedded both in an APOBEC motif and in a CTL epitope, suggesting that APOBEC may facilitate early immune escape. Ten rapidly diversifying sites could not be explained by CTL escape or APOBEC hypermutation, including the most frequently mutated site, in the fusion peptide of gp41. We also examined the distribution, extent, and sequence context of insertions and deletions, and we provide evidence that the length variation seen in hypervariable loop regions of the envelope glycoprotein is a consequence of selection and not of mutational hotspots. Our results provide a detailed view of the process of diversification of HIV-1 following transmission, highlighting the role of CTL escape and hypermutation in shaping viral evolution during the establishment of new infections. 相似文献