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21.
海南脆蛇蜥(Dopasia hainanensis Yang, 1983)为杨戎生根据1号来自海南吊罗山的标本命名,其形态和分子系统发育关系少有人研究。2018年至2019年间,作者获赠2号来自海南脆蛇蜥模式产地的标本和1号来自脆蛇蜥(D. harti)模式产地的组织样。经过形态特征比较和线粒体Cyt b基因序列分析,发现两地样本Cytb基因序列的遗传距离很近(仅有4.96%),且形态差异不明显,难以找到典型鉴别特征。本文研究成果支持海南脆蛇蜥和台湾脆蛇蜥(Ophisaurus formosensis)为脆蛇蜥的同物异名,同时认为越南的“海南脆蛇蜥”可能为一未描述的新种或新亚种。鉴于脆蛇蜥种下遗传差异较大,其种下关系亟待进一步研究。 相似文献
22.
玉米赤霉烯酮生物合成和降解的研究进展 总被引:1,自引:0,他引:1
介绍了玉米赤霉烯酮及其6个衍生物的分子结构,以及玉米赤霉烯酮的生物合成途径。阐述了玉米赤霉烯酮生物合成的基因序列群以及基因簇的表达方式。论述了玉米赤霉烯酮钝化和降解过程, 探讨了玉米赤霉烯酮水解酶在基因工程中的应用研究, 并为今后玉米赤霉烯酮生物工程降解研究提出了建议。 相似文献
23.
Wang-Shan Zheng Yao-Xi He Chao-Ying Cui Ouzhuluobu Dejiquzong Yi Peng Cai-Juan Bai Duojizhuoma Gonggalanzi Bianba Baimakangzhuo Yong-Yue Pan Qula Kangmin Cirenyangji Baimayangji Wei Guo Yangla Hui Zhang Xiao-Ming Zhang Yong-Bo Guo Shu-Hua Xu Hua Chen Sheng-Guo Zhao Yuan Cai Shi-Ming Liu Tian-Yi Wu Xue-Bin Qi Bing Su 《动物学研究》2017,38(3)
The genetic adaptation of Tibetans to high altitude hypoxia likely involves a group of genes in the hypoxic pathway,as suggested by earlier studies.To test the adaptive role of the previously reported candidate gene EP300 (histone acetyltransferase p300),we conducted resequencing of a 108.9 kb gene region of EP300 in 80 unrelated Tibetans.The allele-frequency and haplotype-based neutrality tests detected signals of positive Darwinian selection on EP300 in Tibetans,with a group of variants showing allelic divergence between Tibetans and lowland reference populations,including Han Chinese,Europeans,and Africans.Functional prediction suggested the involvement of multiple EP300 variants in gene expression regulation.More importantly,genetic association tests in 226 Tibetans indicated significant correlation of the adaptive EP300 variants with blood nitric oxide (NO) concentration.Collectively,we propose that EP300 harbors adaptive variants in Tibetans,which might contribute to high-altitude adaptation through regulating NO production. 相似文献
24.
Smoking behavior is a complex, which includes multiple stages in the progression from experimentation to continued use and dependence. The experience of subjective effects, such as dizziness, euphoria, heart pounding, nausea and high, have been associated with varying degrees of persistence and subsequent abuse/dependence of marijuana, cocaine, tobacco and alcohol ( Grant et al. 2005 , Wagner & Anthony 2002 ). Previous studies have reported associations between neuronal nicotinic receptor (CHRN) genes and subjective effects to nicotine. We sought to replicate and expand this work by examining eight single nucleotide polymorphisms (SNPs) in a sample of adult smokers (n = 316) who reported subjective effects following cigarette smoking in a controlled laboratory environment. Two SNPs each in the CHRNB2, CHRNB3, CHRNA6 and CHRNA4 genes were examined. A significant association was found between two SNPs and physical effects reported after smoking the first experimental cigarette. SNP rs2072658 is upstream of CHRNB2 (P‐value = 0.0046) and rs2229959 is a synonymous change in exon 5 of CHRNA4 (P value = 0.0051). We also examined possible functional relevance of SNP rs2072658 using an in vitro gene expression assay. These studies provided evidence that the minor allele of rs2072658 may lead to decreased gene expression, using two separate cell lines, P19 and SH‐SY5Y (18% P < 0.001 and 26% P < 0.001 respectively). The human genetic study and functional assays suggest that variation in the promoter region of CHRNB2 gene may be important in mediating levels of expression of the β2 nicotinic receptor subunit, which may be associated with variation in subjective response to nicotine. 相似文献
25.
《Mycoscience》2019,60(4):246-249
Lentinula edodes secretes laccase (Lcc: EC 1.10.3.2), an industrially useful enzyme. In this study, we introduced and expressed the L. edodes Lcc gene, lcc1, driven by L. edodes glyceraldehyde-3-phosphate dehydrogenase gene promoter into L. edodes. The resulting transformants showed 2-fold Lcc activity than that of the host strain, and expression of the recombinant lcc1 was confirmed by RT-PCR. 相似文献
26.
Xiao-Jie Li Rie Uenishi Saiki Hase Huanan Liao Tee Kok Keng Shigeru Kusagawa Yutaka Takebe 《Virologica Sinica》2007,22(6):426-433
The Asia-Pacific region is a home to 60% of the population in the world and to approximately one quarter of people with HIV/AIDS. Close to a million of people has been infected and a half million people died of AIDS annually in Asia,becoming the second largest epicenter of global AIDS epidemic. Molecular epidemiology has been useful tool to track a course of HIV spread. In-depth knowledge from the studies on molecular epidemiology elucidates the dynamics of HIV spread and the interrelationship of epidemics in the different regions in Asia. 相似文献
27.
Agrobacterium-mediated transformation of Asparagus officinalis L.: molecular and genetic analysis of transgenic plants 总被引:3,自引:0,他引:3
Limanton-Grevet A. Jullien M. 《Molecular breeding : new strategies in plant improvement》2001,7(2):141-150
Four long-term embryogenic lines of Asparagus officinalis were co-cultured with the hypervirulent Agrobacterium tumefaciens strain AGL1Gin carrying a uidA gene and an nptII gene. 233 embryogenic lines showing kanamycin resistance and -glucuronidase (GUS) activity were obtained. Transformation frequencies ranged from 0.8 to 12.8 transformants per gram of inoculated somatic embryos, depending on the line. Southern analysis showed that usually 1 to 4 T-DNA copies were integrated. Regenerated plants generally exhibited the same insertion pattern as the corresponding transformed embryogenic line. T1 progeny were obtained from crosses between 6 transformed plants containing 3 or 4 T-DNA copies and untransformed plants. They were analysed for GUS activity and kanamycin resistance. In three progenies, Mendelian 1:1 segregations were observed, corresponding to one functional locus in the parent transgenic plants. Southern analysis confirmed that T-DNA copies were inserted at the same locus. Non-Mendelian segregations were observed in the other three progenies. T2 progeny also exhibited non-Mendelian segregations. Southern analysis showed that GUS-negative and kanamycin-sensitive plants did not contain any T-DNA, and therefore inactivation of transgene expression could not be responsible for the abnormal segregations. 相似文献
28.
Jean-Jacques Kupiec 《Progress in biophysics and molecular biology》2010,102(1):45-52
It is now widely recognized that gene expression and cellular processes include a probabilistic component. However, this does not essentially modify the theory of genetic programming. This stochastic aspect, which is called noise, is usually conceived as a margin of fluctuation in the way the genetic program functions and the latter remains understood as a specific mechanism guided by genetic information. In contrast, recent data show that proteins do not possess a high level of specificity. They can interact with numerous molecular partners. As a consequence molecular interactions are not simply “noisy”. Because they are subject to large combinatorial interaction possibilities, they are also intrinsically stochastic and must be sorted out by the cell structure. This contradicts the genetic programming theory which is based on the idea that protein interactions are directed by their stereospecificity and genetic information. Taking into account the lack of protein specificity leads to a new theory. Natural selection acts not only in evolution but also in ontogenesis by sorting stochastic molecular interactions. In this frame, the making up of an organism, instead of being a simple bottom-top process in which information flows from genes to phenotypes, is both a bottom-top and top-bottom process. Genes provide proteins, but their stochastic interactions are sorted by selective constraints arising from the cell and multi-cellular structures, which are themselves subject to the action of natural selection. 相似文献
29.
30.
基因组学方法在玉米种质资源研究中的应用 总被引:3,自引:0,他引:3
近年来,分子生物学和植物基因组学得到了飞速发展,包括分子标记技术在内的基因组学方法在玉米种质资源研究中得到了广泛应用。本将对玉米种质资源研究的主要领域如玉米的起源和进化、遗传多样性的形成机制及评估、基于多样性的新基因发掘等方面的最新进展进行评述,并提出我国在应用基因组学方法进行玉米种质资源研究的策略。 相似文献