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261.
262.
麦红吸浆虫Sitodiplosis mosellana(Gehin)是一种世界性的小麦害虫。为获得其转录组信息,本研究采用新一代高通量测序技术Illumina HiSeq TM 2000对麦红吸浆虫成虫转录组进行测序。共获得转录组样本数据量为27.88 G,经分析共获得59257个Unigenes,总长度49861164 bp,最短20 bp,最长29282 bp,平均长度841 bp。将Unigenes序列与NR、NT、Swiss-Prot、KEGG、GO和KOG数据库进行比对(e≤10-10),共获得95029个结果。通过GO功能分类,共有19584个Unigenes在GO数据库中细胞组分、分子功能和生物学过程等3大类50个功能组中找到对应。与KOG数据库进行比对,共有11279个麦红吸浆虫Unigenes被注释,按功能大致可分为26类。通过KEGG pathways分析,共有9110个麦红吸浆虫Unigenes被注释,分别归属于细胞进程、环境信息进程、遗传信息进程、新陈代谢和有机体系统5大类代谢途径,主要包括细胞生长与死亡、细胞运动、信号转导、能量代谢等32类代谢途径。CDS预测发现30088条序列可被编码,占全部基因的50.78%。SSR位点查找发现,在59257个Unigenes中共找到36323个SSR位点,发生率为61.30%。本研究获得的巨大的麦红吸浆虫转录组信息,为麦红吸浆虫的功能基因挖掘提供了重要的信息资源。 相似文献
263.
Wang Xingyu Huang Kun Jiang Haini Hua Lijuan Yu Weiwei Ding Dan Wang Ke Li Xiaopan Zou Zhong Jin Meilin Xu Shuyun 《中国病毒学》2020,35(6):793-802
Virologica Sinica - COVID-19 patients can recover with a median SARS-CoV-2 clearance of 20 days post initial symptoms (PIS). However, we observed some COVID-19 patients with existing... 相似文献
264.
Hu Yongfeng Kang Ying Liu Xi Cheng Min Dong Jie Sun Lilian Zhu Yafang Ren Xianwen Yang Qianting Chen Xinchun Jin Qi Yang Fan 《中国科学:生命科学英文版》2020,63(10):1522-1533
An improved understanding of the lung microbiome may lead to better strategies to diagnose, treat, and prevent pulmonary tuberculosis(PTB). However, the characteristics of the lung microbiomes of patients with TB remain largely undefined. In this study, 163 bronchoalveolar lavage(BAL) samples were collected from 163 sputum-negative suspected PTB patients. Furthermore, 12 paired BAL samples were obtained from 12 Mycobacterium tuberculosis-positive(MTB+) patients before and after negative conversion following a two-month anti-TB treatment. The V3–V4 region of the 16 S ribosomal RNA(rRNA) gene was used to characterize the microbial composition of the lungs. The results showed that the prevalence of MTB in the BAL samples was 42.9%(70/163) among the sputum-negative patients. The α-diversity of lung microbiota was significantly less diverse in MTB+ patients compared with Mycobacterium tuberculosis-negative(MTB–) patients. There was a significant difference in β-diversity between MTB+ and MTB– patients. MTB+ patients were enriched with Anoxybacillus, while MTB– patients were enriched with Prevotella, Alloprevotella, Veillonella, and Gemella. There was no significant difference between the Anoxybacillus detection rates of MTB+ and MTB– patients. The paired comparison between the BAL samples from MTB+ patients and their negative conversion showed that BAL negative-conversion microbiota had a higher α-diversity. In conclusion, distinct features of airway microbiota could be identified between samples from patients with and without MTB. Our results imply links between lung microbiota and different clinical groups of active PTB. 相似文献
265.
266.
Ba Limin Wang Zhenbao Liu William J Wu Dongxun Xiang Wangzhen Qi Peng Dong Chunna Hu Yanxin Lu Ping Xiao Jin Yu Changyuan 《中国科学:生命科学英文版》2020,63(10):1604-1607
正Dear Editor,Swine major histocompatibility complex (MHC) is a highly polymorphic gene in pigs and is also called swine leukocyte antigen (SLA)(Fan et al., 2018). SLA is divided into three major categories, SLA Ⅰ (SLA-1,-2,-3), SLA Ⅱ, and SLA Ⅲ(Smith et al., 2005). SLA Ⅰ plays an important role in cellular immunity which can eliminate viruses and other foreign 相似文献
267.
Jin Chen Daolong Xu Lumeng Chao Haijing Liu Yuying Bao 《Microbial biotechnology》2020,13(5):1390-1402
Root-associated microbiomes play significant roles in plant productivity, health and ecological services. However, our current understanding of the microbial assemblages in the rhizosphere and endosphere of herbage is still limited. To gain insights into these microbial assemblages, Illumina MiSeq high-throughput sequencing was performed to investigate the characteristics of microbial communities of an herbage, Leymus chinensis. Hierarchical clustering analysis and principal coordinate analysis (PCoA) results showed that microbial communities of the rhizosphere and endosphere samples were clearly distinguished. Rhizosphere soil communities showed a greater sensitivity than root endosphere communities using linear discriminant analysis (LDA) effect size (LEfSe). Rhizosphere and endosphere communities performed their respective functions in the soil as a cohesive collective, and Rhizobiales were observed to function as generalists. Redundancy analysis (RDA) and variance partitioning analysis (VPA) results revealed that the contribution of the interaction between soil physicochemical parameters and soil enzymes was greater than their individual contributions. In summary, this study is the first to elucidate the microbial diversity and community structure of L. chinensis and compare the diversity and composition between rhizospheric and endosphere microbiomes. 相似文献
268.
Duwen Zeng Chenxi Qiu Yu Shen Jin Hou Zailu Li Jixiang Zhang Shuai Liu Jianli Shang Wensheng Qin Lili Xu Xiaoming Bao 《Microbial biotechnology》2020,13(6):2008-2019
Saccharomyces cerevisiae is the preferred source of RNA derivatives, which are widely used as supplements for foods and pharmaceuticals. As the most abundant RNAs, the ribosomal RNAs (rRNAs) transcribed by RNA polymerase I (Pol I) have no 5′ caps, thus cannot be translated to proteins. To screen high-nucleic-acid content yeasts more efficiently, a cap-independent protein expression system mediated by Pol I has been designed and established to monitor the regulatory changes of rRNA synthesis by observing the variation in the reporter genes expression. The elements including Pol I-recognized rDNA promoter, the internal ribosome entry site from cricket paralytic virus which can recruit ribosomes internally, reporter genes (URA3 and yEGFP3), oligo-dT and an rDNA terminator were ligated to a yeast episomal plasmid. This system based on the URA3 gene worked well by observing the growth phenotype and did not require the disruption of cap-dependent initiation factors. The fluorescence intensity of strains expressing the yEGFP3 gene increased and drifted after mutagenesis. Combined with flow cytometry, cells with higher GFP level were sorted out. A strain showed 58% improvement in RNA content and exhibited no sequence alteration in the whole expression cassette introduced. This study provides a novel strategy for breeding high-nucleic-acid content yeasts. 相似文献
269.
The acquisition of sulfur from environment and its assimilation is essential for fungal growth and activities. Here, we describe novel features of the regulatory network of sulfur metabolism in Ogataea parapolymorpha, a thermotolerant methylotrophic yeast with high resistance to harsh environmental conditions. A short bZIP protein (OpMet4p) of O. parapolymorpha, displaying the combined structural characteristics of yeast and filamentous fungal Met4 homologues, plays a key role as a master regulator of cell homeostasis during sulfur limitation, but also its function is required for the tolerance of various stresses. Domain swapping analysis, combined with deletion analysis of the regulatory domains and genes encoding OpCbf1p, OpMet28p, and OpMet32p, indicated that OpMet4p does not require the interaction with these DNA-binding cofactors to induce the expression of sulfur genes, unlike the Saccharomyces cerevisiae Met4p. ChIP analysis confirmed the notion that OpMet4p, which contains a canonical bZIP domain, can bind the target DNA in the absence of cofactors, similar to homologues in other filamentous fungi. Collectively, the identified unique features of the O. parapolymorpha regulatory network, as the first report on the sulfur regulation by a short yeast Met4 homologue, provide insights into conservation and divergence of the sulfur regulatory networks among diverse ascomycetous fungi. 相似文献
270.
Hao Wang Huiying Liu Guangmin Cao Zhiyuan Ma Yikang Li Fawei Zhang Xia Zhao Xinquan Zhao Lin Jiang Nathan J. Sanders Aime T. Classen Jin‐Sheng He 《Ecology letters》2020,23(4):701-710
Satellite data indicate significant advancement in alpine spring phenology over decades of climate warming, but corresponding field evidence is scarce. It is also unknown whether this advancement results from an earlier shift of phenological events, or enhancement of plant growth under unchanged phenological pattern. By analyzing a 35‐year dataset of seasonal biomass dynamics of a Tibetan alpine grassland, we show that climate change promoted both earlier phenology and faster growth, without changing annual biomass production. Biomass production increased in spring due to a warming‐induced earlier onset of plant growth, but decreased in autumn due mainly to increased water stress. Plants grew faster but the fast‐growing period shortened during the mid‐growing season. These findings provide the first in situ evidence of long‐term changes in growth patterns in alpine grassland plant communities, and suggest that earlier phenology and faster growth will jointly contribute to plant growth in a warming climate. 相似文献