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1.
Molecular Biology - The Drosophila melanogaster Maleless (MLE) protein is a conserved helicase involved in a wide range of gene expression regulation processes. A MLE ortholog, named DHX9, was...  相似文献   

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中国蔓藓科两新种和五新分布种   总被引:1,自引:0,他引:1  
报道我国蔓藓科植物2新种:云南灰气藓Aerobryopsis yunnanensis X.J.Li et D.C.Zhang,sp.nov.芒叶灰气藓Aerobryopsis aristifolia X.J.Li,S.H.Wu et D.C.Zhang,sp.nov.以及5个新记录:波叶毛扭藓Aerobryidium crispifolium (Broth.et Geh.)Fleisch,ex Broth,膜叶灰气藓Aerobryopsis membranacea(Mitt.Broth.纤细灰气藓Aerobryopsis subleptostigmata Broth.et Par.,卷叶悬藓Barbella convolvens(Mitt.)Broth,斯氏悬藓Barbella stevensii(Ren.et Card.)Fleisch.ex Broth.  相似文献   

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记述中国盾蚧科2新种:拟额瘤并盾蚧Pinnaspis pseudotuberculatua sp.nov.和云南兜盾蚧Duplachionaspis yunnanensis sp.nov.。模式标本保存在西北农林科技大学昆虫博物馆。  相似文献   

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《Journal of Asia》2007,10(2):113-115
Two species of the family Incurvariidae, Vespina nielseni Kozlov and Paraclemensia monospina Nielsen, are reported for the first time from Korea. The morphological characteristics of adults and the female genitalia of the two species are redescribed briefly, with illustrations.  相似文献   

6.
Four independent genes encoding various variants of the hRPB11 subunit of Homo sapiens RNA polymerase II were revealed in human chromosome 7. Three genes (POLR2J1, POLR2J2, and POLR2J3) form a cluster of total length of 214 530 bp in the genetic locus 7q22.1 on the long arm of chromosome 7 (contig NT_007933). The fourth gene (POLR2J4, 31 040 bp) was localized in the cytogenetic locus 7p13 of the short arm of chromosome 7 (contig NT_007819). An analysis enabled us to refine dissimilar experimental data on the mapping of the hRPB11 subunit gene on chromosome 7. In particular, the presence of three sites of its localization according to data on hybridization with fluorescent-labeled probes (the FISH method) was explained. It was established that, upon the expression of the four human POLR2J genes, at least 14 types of mature mRNAs encoding somewhat differing hRPB11 isoforms can be synthesized. Eleven of these mRNAs were revealed (as full-length copies or clearly identifiable fragments) in the available databases of expressed sequence tags and cDNAs. The most probable scheme of origination of the multiple genes of the POLR2J family as a result of three consecutive segmented duplications increasing in size was proposed and substantiated. On the basis of the scheme, some assumptions on the pathways of evolution of separate human genes and the mechanisms of generation of protein diversity in higher eukaryotes were made.  相似文献   

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《Cell reports》2014,6(2):346-356
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With PCR products as probes, we have cloned two new cry-type genes from Bacillus thuringiensis subsp. wuhanensis. The deduced amino acid sequence of the first clone is 77.3% identical to Cry1Ga1. The deduced protein sequence of the second clone is 69.8–78.7% identical to that of Cry1B group. The nomenclature assignment of these two clones is, therefore, named Cry1Gb1 and Cry1Bd1, respectively. The Cry1Bd1 is toxic to Plutella xylostella larvae, and the Cry1Gb1 is toxic to Pieris rapae larvae. Received: 2 August 1999 / Accepted: 18 October 1999  相似文献   

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对胶毛藻科植物优美胶毛藻[Chaetophora elegans(Roth)Agardh]和羽枝竹枝藻[Draparnaldia plumosa(Vauch) Agardh]进行了室内培养,对它们自游动孢子萌发到成熟丝状体形成等生活史各阶段都进行了详细观察,并做了活体显微镜照相记录。结果显示:(1)优美胶毛藻的游动孢子较小,直径为9~11μm,顶端具4条等长鞭毛,自母细胞释放后,游动孢子固定在基质上萌发,萌发类型为直立式,顶端细胞发育为直立系统,其直立系统为二叉状分枝,无明显主枝,侧枝发达,分枝顶端细胞渐尖或毛状,各级分枝细胞大小基本相同,圆柱形,宽约为6~8μm,长约为10~12μm。基细胞发育为匍匐系统,首先产生匍匐枝,由它产生假根。随生长,直立系统下部的细胞产生次生假根,成熟的优美胶毛藻外观近球形,与野生胶毛藻的形态相似。(2)羽枝竹枝藻游动孢子产生于母细胞,游动孢子体积较大,直径约为30μm左右,顶端具4条等长鞭毛。游动孢子从母细胞内释放后,固定在基质上萌发,萌发类型亦为直立式,顶端细胞发育为直立系统,其直立系统为分枝丝状体,主枝粗壮,细胞圆柱形,长约为50~60μm,宽约为48~50μm,内有多个蛋白核;侧枝细胞为长圆形,长约为40~50μm,宽约为17~19μm,分枝顶端的细胞尖细或为毛状。基细胞发育为假根和匍匐枝。当藻体成熟时,直立系统下部的细胞产生次生假根。  相似文献   

10.
We cloned and sequenced two new Verotoxin 2 (VT2) variant genes: one from an Escherichia coli strain from a case of bovine diarrhea and the other from an E. coli strain from a patient with diarrhea. The nucleotide and amino acid sequences of these two genes were highly homologous with, but distinct from those of the VT2, VT2vha, VT2vhb, SLT-IIv (VT2vp1) and SLT-IIva (VT2vp2) genes. Their nucleotide sequences were much more closely homologous to that of VT2vh than to that of VT2vp. Search for these two new genes in other Verocytotoxin-producing E. coli strains resulted in the isolation of 2 strains carrying one of the new VT2 variant genes, one strain from Tokyo and the other from Canada.  相似文献   

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I introduce a range of examples of different causal hypotheses about human mate selection. The hypotheses I focus on come from evolutionary psychology, fluctuating asymmetry research and chemical signaling research. I argue that a major obstacle facing an integrated biology of human behavior is the lack of a causal framework that shows how multiple proximate causal mechanisms can act together to produce components of our behavior.  相似文献   

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Axs mutations disrupt both the progression of the meiotic cell cycle and meiotic chromosome segregation in Drosophila. Axs protein co-localizes with endoplasmic reticulum components and is present within a novel structure ensheathing the meiotic spindle. We show that Axs encodes the founding member of a eukaryotic family of trans-membrane proteins.  相似文献   

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Entomological Review - A new genus, Ptorthus gen. n. with the type species Ptorthus kermanicus sp. n., is described from Iran (Fars Province), and Adolenda marusiki sp. n., from India (Uttar...  相似文献   

14.
P. Seperack  M. Slatkin    N. Arnheim 《Genetics》1988,119(4):943-949
Members of the rDNA multigene family within a species do not evolve independently, rather, they evolve together in a concerted fashion. Between species, however, each multigene family does evolve independently indicating that mechanisms exist which will amplify and fix new mutations both within populations and within species. In order to evaluate the possible mechanisms by which mutation, amplification and fixation occur we have determined the level of linkage disequilibrium between two polymorphic sites in human ribosomal genes in five racial groups and among individuals within two of these groups. The marked linkage disequilibrium we observe within individuals suggests that sister chromatid exchanges are much more important than homologous or nonhomologous recombination events in the concerted evolution of the rDNA family and further that recent models of molecular drive may not apply to the evolution of the rDNA multigene family.  相似文献   

15.
新疆蚁科昆虫42种中国新记录   总被引:5,自引:0,他引:5  
用传统分类方法并结合电镜扫描技术,对采自新疆各地的蚁类标本进行整理、鉴定,发现有42种,均为中国首次记录。所有研究标本均保存在新疆大学生命科学与技术学院昆虫标本室。  相似文献   

16.
Yi JM  Kim HM  Lee WH  Kim HS 《Current microbiology》2002,44(3):216-220
A human endogenous retroviral family (HERV-W) has recently been described that is related to multiple sclerosis-associated retrovirus (MSRV) sequences. By using the PCR approach with human genomic DNA derived from cancer cell lines (HepG2, Jurkat, MCF7, UO-31), five env fragments of HERV-W family were newly identified and analyzed. They showed a high degree of nucleotide sequence similarity (94–99%) with that of the HERV-W. Translation of the env fragments showed no frameshift and termination codon by deletion/insertion or point mutation in clones HepG2-1 and JUR-3. The ratio of synonymous to non-synonymous substitutions indicated that negative selective pressure is acting on HepG2-1 and JUR-3 sequences. These env gene sequences could be associated with an active provirus in human cancer cells (HepG2 and Jurkat). The HepG2-1 and JUR-3 showed sister relationship with the HERV-W and W-7-1 derived from human Chromosome (Chr) 7. Phylogenetic analysis from the HERV-W family indicated close relationships of the env gene sequences across human chromosomes. Received: 12 March 2001 / Accepted: 12 July 2001  相似文献   

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本文记述了壮蟹蛛属Stiphropus和斜蟹蛛属Loxobates蜘蛛2新种,分别命名为镰壮蟹蛛,新种Stiphropus falciformus sp.nov.和刺斜蟹蛛,新种Loxobates spiniformis sp.nov..壮蟹蛛属Stiphropus在我国尚属首次记述.壮蟹蛛属Stiphropus Gerst(a)cker,1873新纪录属Stiphropus Gerst(a)cker,1873479;Ono,198059模式种Stiphropus lugubris Gerst(a)cker,1873 鉴别特征本属与革蟹蛛属Coriarachne Thorell,1870(Song & Zhu,1997,61)在体型上非常相似,但具以下区别头 胸部长大于宽,而不是宽大于长;步足和触肢具许多羽状毛(plumose hairs)(figs.1 C~D),但后者无;雄蛛插入器大,小刀状(cultrate)或acerate,后者小而呈刺状;雌蛛外雌器中隔骨化强烈,而后者不明显.镰壮蟹蛛,新种Stiphropus falciformus sp.nov.正模♂大理市凤仪镇公山,25°35'N,100°18'E,2002年5月21日,杨自忠采;副模1♀,地点同前,2002年6月29日,杨自忠采;3♂,元谋县元马镇,25°42'N,101°53'E,2005年9月12日,李巧采;1♂,元谋县老城乡,25°37'N,101°54'E,2005年9月10日,李巧采.词源学本新种种名根据插入器的形状而拟定.鉴别特征本新种与眼斑壮蟹蛛Stiphropus ocellatus Thorell,1887(Ono,1980 b64,flgs.12~27)相似,但具以下区别插入器比后者长而宽;外侧突比后者短而宽.斜蟹蛛属Loxobates Thorell,1877 Loxobates Thorell,1877495;Song & Zhu,199740;Song,Zhu & Chen,1999481模式种Loxobates ephippiatus Thorell,1877刺斜蟹蛛,新种Loxobates spiniformis sp.nov.正模♂云南省大理市点苍山,25°58'N,99°52'E,2002年6月9日;副模1♀,4 ♂,地点同前,2004年5月22日,海拔2 300~2 500 m,杨自忠采;副模3♀,8♂,地点同前,2005年5月31日,杨自忠、杨飞采.词源学本新种名根据雄蛛触肢胫节外侧突起的形状而拟定.鉴别特征本新种雄蛛的插入器形状与小斜蟹蛛Loxobates minorOno,2001(p.208,figs.6~8)相似,但具以下区别胫节外侧突基部螺旋状,端部刺状(figs.2.D~E),后者小而呈指状;腹侧突腹面观指状而不呈钝齿状.雌蛛与大东斜蟹蛛L.daitoensis Ono,1988(p.43,figs.27~33)相似,外雌器近"U"字形、交配管长而不同于后者.  相似文献   

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根据前期耐盐芯片研究提供的两条EST序列设计引物,利用RACE技术从番茄耐盐品种Edkawi中克隆了其5’和3’片段,并拼接成全长cDNA,分别命名为SISRGl和SISRG2。两个基因序列在GenBank中的登录号为EU670751和EU670752,其大小分别为1300bp和1810bp,编码蛋白分别为309和499个氨基酸。半定量RT,PCR表明SISRGl在番茄茎、叶、花中表达较强,在所检测的其它组织中表达很弱,SISRG2在叶和花中表达量最高,其次为茎和根,在果实中表达微弱。盐胁迫表达谱结果显示SISRGl在盐处理的Edkawi中缓慢增强,SISRG2则在盐胁迫后表达迅速增强,在未进行盐胁迫的对照中,两个基因的表达趋势均为减弱。本研究为番茄抗逆研究提供了新的候选基因资源。  相似文献   

20.
刘冬  陈军 《蛛形学报》2010,19(1):1-6
记述我国三甲螨科1新记录属:印三甲螨属Indotritia Jacot,1928及中国2新记录种:爪哇印三甲螨Indotritia javensis(Sellnick,1923)和波状印三甲螨Indotritia undulata Bayoumi & Mahunka,1979,给出了形态描述和特征图。所有标本材料均保存在中国科学院动物研究所国家动物博物馆。  相似文献   

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