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Measuring the diffusion of genes between diverging taxa through zones of secondary contact is an essential step to understand the extent and nature of the reproductive isolation that has been achieved. Previous studies have shown that the ocellated lizard (Lacerta lepida Daudin, 1802) has endured repeated range fragmentation associated with the climatic oscillations of the Plio‐Pleistocene that promoted diversification of many different evolutionary units within the species. However, the oldest divergence within the group is estimated to have occurred much earlier, during the Miocene, around 9 Ma and corresponds to the split between the subspecies Lacerta lepida nevadensis Buchholz (1963) and Lacerta lepida lepida Daudin (1802). Although these two evolutionary units have documented genetic and morphological differentiation, most probably accumulated during periods of allopatry, little is known about patterns of gene flow between them. In this study, we performed a population genetic analysis of a putative area of secondary contact between these two taxa, using mtDNA and microsatellite data. We assessed levels of gene flow across the contact zone to clarify to what extent gene flow may be occurring. Hybridization between the subspecies was observed by the presence of genetically introgressed individuals. However, the overall coincidence of mitochondrial and multilocus nuclear clines and generally steep clines support the idea that this contact zone is acting as a barrier to gene flow. Taken together, these results suggest that L. l. lepida and L. l. nevadensis are in independent evolutionary trajectories and should be considered as two different species.  相似文献   
2.
以红菇属大白菇Russula delica和美丽红菇Russula lepida子实体为材料,利用离子交换柱层析、凝胶过滤层析的手段,分离获得新的凝集素RDL和RLL。结合凝胶过滤层析和SDS-PAGE的手段,确定RDL和RLL分别是分子量为60kDa和32kDa的双亚基蛋白,其N-末端部分氨基酸序列分别为GLKLAKQFAL和VWYIVAIKTDVPRTT。性质研究表明,RDL在20-70℃、低于25mmol/L HCl或12.5mmol/L NaOH下稳定,其凝集活性可以被邻硝基苯酚-β-D呋喃型半乳糖苷(25mmol/L)和菊糖(50mmol/L)所抑制;RDL具有抑制人肝癌Hep G2和人乳腺癌MCF7细胞增殖以及HIV-1反转录酶(RT)的活性,其半抑制浓度IC50分别为0.88μmol/L、0.52μmol/L和0.26μmol/L。RLL在20-70℃、低于12.5mmol/L HCl或NaOH下稳定,其凝集活性可以被菊糖(25mmol/L)和邻硝基苯酚-β-D呋喃型半乳糖苷(100mmol/L)所抑制;RDL具有抑制人肝癌Hep G2和人乳腺癌MCF7细胞增殖的活性,其半抑制浓度IC50分别为1.60μmol/L和0.90μmol/L,但不具有抑制HIV-1 RT的活性。  相似文献   
3.
记述中国绿刺蛾属Parasa Moore 2新种:镇雄绿刺蛾P.zhenxiongica sp.nov.和西藏绿刺蛾P.xizangensis sp.nov.及3中国新纪录种:同宗绿刺蛾P.gentiles(Snellen)、缅媚绿刺蛾P.kalawensis Orhant和榴绿刺蛾P.punica (Herrich-Schaffer).另外,对中国绿刺蛾P.sinica Moore、双齿绿刺蛾P.hilarata(Staudinger)和青绿刺蛾P.hilarula (Staudinger)的混淆与误定进行了更正.提供了它们的成虫彩色照片和新种的外生殖器特征图.模式标本保存在中国科学院动物研究所.  相似文献   
4.
A new aristolane sesquiterpenoid named rulepidol was isolated from the fruiting body ofRussula lepida Fr. Its structure was elucidated as (1aa,5a,7a,7aa,7b)-1,1a,4,5,6,7,7a,7b-octahydro-5-hydroxy-1,1,7,7a-tetramethyl-5H-cyclopropa[α]naphthalen-2-one mainly by 1D and 2D-NMR techniques.  相似文献   
5.
刺蛾科幼虫是我国常见的农林业害虫之一,其体表长有防御性的有毒刺毛,会伤害接触者,使其产生瘙痒、刺痛、丘疹、红肿、皮炎等症状.本研究利用体视显微镜、扫描电镜对褐边绿刺蛾Parasa consocia末龄幼虫的刺毛形态结构进行了观察,将不同刺毛提取物进行小鼠足底皮下注射,测试刺激活性,并使用SDS-PAGE电泳对提取物成分...  相似文献   
6.
Insects depend on lectins for non‐self recognition and clearance of invading pathogens. Naturally occurring lectin showing specificity for galactose was purified from the serum of lepidopteran pest Parasa lepida by affinity chromatography using Sepharose 6B coupled with galactose as a gel matrix. Preliminary studies on crude serum agglutinin revealed that the agglutinin molecule showed varying degrees of specificity to avian and mammalian red blood cells tested. Among them, the highest titer of 128 was recorded against rabbit red blood cell type. The agglutinin molecule in the crude serum was stable up to 60°C and at pH between 6 and 9. Also, the hemagglutinating activity was neither dependent on divalent cations nor sensitive to ethylenediaminetetraacetic acid treatment. Galactose inhibited the hemagglutinating activity at minimum inhibitory concentration of 12.5 mM and hence it was used as a ligand for affinity chromatography. Native polyacrylamide gel electrophoresis analysis revealed a single band and the molecular weight of the lectin was found to be approximately 90 kDa. Bacterial agglutination activity of the purified lectin with two significant toxin bacteria, namely Salmonella typhi and Bacillus thuringiensis, was observed.  相似文献   
7.
从鳞盖红菇(Russula lepida Fr.)的氯仿/甲醇(1:1)部分分离得到一新化合物rulepidol(1),其结构经现代波谱技术鉴定为一aristolane型倍半萜。  相似文献   
8.
上海市绿化植物中四种常见刺蛾的生态位及其种间竞争   总被引:1,自引:0,他引:1  
为明确上海城市绿化植物中常见刺蛾的种间关系,定量研究了黄刺蛾、桑褐刺蛾、丽绿刺蛾及褐边绿刺蛾在营养、时间、空间资源序列上的生态位指数。结果表明:褐边绿刺蛾比其它刺蛾能较广泛地利用寄主资源,生态位宽度指数为0.5447;黄刺蛾、桑褐刺蛾在时间序列上占有较大优势,生态位宽度指数分别为0.4304和0.4415;而黄刺蛾的茧则在空间资源利用中优于其它刺蛾,生态位宽度指数为0.5441。在种间,桑褐刺蛾与丽绿刺蛾利用营养资源较为接近,其生态位重叠指数(2.6647)、生态位相似比例(0.5199)和种间竞争系数(0.7015)均高于其它共存种类;黄刺蛾和桑褐刺蛾利用时间资源较相似,生态位相似比例和种间竞争系数分别为0.4846、0.5222;而桑褐刺蛾和褐边绿刺蛾则在空间资源利用中较为接近,其生态位重叠指数(2.7495)、生态位相似比例(0.9165)和种间竞争系数(0.9959)在共存种间均为最高。  相似文献   
9.
研究实验条件下培养红菇菌丝和发酵液对几种肠道致病菌的抑菌活性。结果发现其对大肠埃希菌具有特异性抑制,对其他菌的抑制较弱。初步确定了最小抑菌活性,认为红菇多糖具有一定的抑菌潜力。  相似文献   
10.
褐边绿刺蛾的取食行为和取食量   总被引:2,自引:1,他引:2  
观察褐边绿刺蛾Parasa consocia Walker2个世代幼虫取食杨树叶片的习性。结果表明,第1代幼虫7龄,幼虫期平均取食量167.7cm2/头,取食持续时间26d;第2代幼虫8龄,幼虫期平均取食量170.5cm2/头,取食持续时间27d。2个世代末龄幼虫取食量最大,占整个取食量的80%左右,4~5龄幼虫是防治的关键龄期。  相似文献   
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