黑腹果蝇野生型和翅形眼色异常突变型的求爱歌的比较研究

黑腹果蝇(D.melanogaster)雄蝇发出的求爱歌系由两个不同的成分——正弦歌和脉冲歌组成。正弦歌在刺激雌蝇发情上可能起着重要的作用,而脉冲歌则关系到种的识别。 在脉冲歌的诸成分中,脉冲间间隔(ipi)特别重要。我们对野生型和突变型SM_1Cy/Pm,SM_1Cy/+和+/Pm进行了研究。虽然突变型有异常的翅形和异常的眼色,但实验结果表明,野生型和上述突变型的ipi平均值是一致的。     

果蝇nasuta亚群求爱歌的种间识别与进化遗传学研究

果蝇ｎａｓｕｔａ亚群由１４个种、亚种和分类群组成,广泛分布于印度－太平洋区域。本文首次记录了ｎａｓｕｔａ亚群种的求爱歌,测量了脉冲歌时域模式的参数：脉冲串间隔（ＩＢＩ）、脉冲间隔（ＩＰＩ）、脉冲串时间长度（ＰＴＬ）、每个脉冲串的脉冲数（ＰＮ）、脉冲时间长度（ＰＬ）、波动周期时间长度（ＣＬ）。采用计算机声谱分析技术,作出求爱歌信号的三维数字功率谱图,进行频率分析。发现Ｄ．ｐｕｌａｕｎａ和Ｔａｘｏｎ－Ｆ不发出求爱歌声信号,视觉在交配中可能起重要作用。对其余种、亚种和分类群的求爱歌分析表明,ｎａｓｕｔａ亚群种的求爱歌分为脉冲歌和正弦歌。对部分种的正反交Ｆ１求爱歌分析表明,脉冲歌时域参数,如ＩＰＩ平均值为Ｘ染色体连锁或常染色体多基因控制,正弦歌频率偏向母方。根据不同种、亚种和分类群脉冲歌的时域模式构建ｎａｓｕｔａ亚群的系统树,对亚群中不同种、亚种和分类群的亲缘关系进行讨论。     

时域—频域结合分析法—一种分析果蝇求爱歌的新方法

我们设计了一种时域-频域结合分析法,并用此方法分析了6个种群12种果蝇的求爱歌,发现如果将时域与频域的研究结合起来,对求爱歌进行频谱分析,可以定量地揭示出求爱歌的频域特性及其在时域上的细微变化。我们还对果蝇求爱歌的时域模式进行了初步的探讨,发现它们是在同一基本成分上进行调制而产生的,亲缘关系较近的种具有相近的调制方式。在对杂交后代的求爱歌的频谱分析中,我们还发现频谱上的某些特点是能够遗传的。这一新的研究方法为果蝇的进化遗传学和神经遗传的研究提供了一种新的手段。     

用新的计量方法研究黑腹果蝇的求爱歌

对雄果蝇求爱脉冲歌的研究已有多年的历史,但对脉冲间隔的计量方法并不方便。本文介绍我们采用微机终端计时新技术,自动对脉冲进行计数,可在范围更为广泛的数据信息内,对果蝇脉冲歌进行测量统计,对ipi分布中纵数与平均值的关系提出我们的看法,并首次对ipf及npb的分布进行了研究。     

果蝇在行为遗传学研究中的重要性及其求爱行为的研究现状

果蝇是研究行为遗传学的良好材料。果蝇的性行为包括交尾前在视觉、听觉、嗅觉、触觉、刺激的传递和接受等方面相当复杂的“求爱行为”,受种特异性配偶认识系统的支配。雄果蝇的求爱歌包括正弦歌和脉冲歌,具有种的特异性。果蝇的信息素起“性引诱”作用,雌果蝇腹部的内部组织可能是产生某种信息素的场所。     

北京果蝇的调查研究

1957年5月到10月调查了北京地区的果蝇种群。共有8种:D.immigrans,D.virilis,D.suzukii,D.auraria D.takahashii,D.bizonata.D.transversa,D.melanogaster. 除D.melanogaster和D.virilis在北京已有记录外。其他6种在北京及附近地区的分布过去文献尚无记载。其中D.bizonata为中国新记录。 本文说明了北京地区果蝇的季节变动,对各种果蝇的发育历程作了观察记录,并列出1个北京果蝇检索表。     

以ND4L和ND4基因为标记探讨黑腹果蝇种组的系统发育关系

多年来的形态学、染色体组学以及DNA序列几个方面的研究均没有很好地阐明黑腹果蝇种组内的系统发育关系。本实验测定了33个样品的ND4和31个样品的ND4L基因序列,以D．obscuroides为外群,用最大简约法和Bayesian法分别构建进化树。结果表明两种方法构建的拓扑结构一致,而且大部分支系的支持率较高。整个黑腹果蝇种组分成三大谱系：1）montium种亚组;2）ananssae种亚组;3）Oriental种亚组（melanogaster、ficsphila、eugracilis、elegans、suzukii、takahashii）。montium是最早分化的种亚组。在第三谱系中,melanogaster分化得最早;然后依次是ficsphila,eugracilis,elegans;suzukii与takahashii为姐妹种亚组,最后分化。     

period基因的Thr—Gly区段在果蝇和部分双翅目昆虫中的分子进化特征

以亲缘关系极近的近缘种类群、中等距离的远缘种类群为对象,分析生物钟基因period的Thr-Gly区段的分子进化特征,发现Thr-Gly区段在果蝇和部分双翅目昆虫中未曾经历性选择和其他定向的正选择。Thr-Gly区段在果蝇nasuta亚群中的分子进化速率为10.4×10     

三黄果蝇(Drosophila trilutea)近黄果蝇(D.paralutea)的有丝分裂中期染色体

这两种果蝇隶属果蝇科 Drosophilidae 果蝇属 Drosophila (Sophophora) 黑腹果蝇 D.melanogaster 种组(species group)中的D.takahashii 亚组(subgroup)。Bock和Wheeler(1972)在报道新种的文献中,曾记述其有丝分裂中期染色体的形态结构为2对中着丝粒(V形),1对棒状(R)。其中X染色体为棒状,Y染色体稍短。据此,其二倍体染色体数目推测为2n=6。我们观察的结果则与之显然不同。     

黑腹果蝇种组的核型与进化研究

观察了国内黑腹果蝇种组34种果蝇的有丝分裂中期核型,其中首次描述了一些新核型。系统地分析了黑腹果蝇种组8个种亚组之间的核型进化关系及种间亲缘关系。结果是:elegans种亚组的核型为A型;eugracilis、melanogaster和ficusphila种亚组的核型为C型;takahashii和suzukii种亚组的核型为C型和D型;montium种亚组的核型为B、C、C’、D、D’、和E型;ananassae种亚组的核型为F、G和H型。从核型分化的角度可以将黑腹果蝇种组分为5个谱系:elegans,eugracilis-melanogaster-ficusphila,takkahashii-suzukii,montium,ananassae。这与2004年Yang等的观点基本一致,正好从核型进化的角度验证了Yang通过DNA序列分析所得到的结果。差别只在于elegans种亚组,作者把它单独列为一支,认为是祖先种亚组。通过选取同一种果蝇的几个不同地域单雌系的核型分析,结果表明:同一种果蝇的核型存在地域差异。这种差异可能是由于不同生境造成,也可能是本身进化程度的差异,或是两种因素相互作用的结果。     

一个果蝇新种分类地位的研究—从形态水平到分子水平

本文从形态水平到分子水平,对疑难种D.liui.sp.n.的分类地位作了研究。结果表明D.liui.sp.n.确实是一个新种,是takahashii亚种组中的一个新成员,从而明确了该种的分类地位。     

Mating system evolution in sperm-heteromorphic Drosophila

In Drosophila species of the obscura group, males exhibit sperm-heteromorphism, simultaneously producing both long sperm, capable of fertilization, and short sperm that are not. The production of multiple sperm types calls into question whether mating system correlates, such as sperm length and number trade-offs and female remating behavior, are the same as previously described in sperm-monomorphic systems. We examine three obscura group species, D. pseudoobscura, D. persimilis, and D. affinis that differ significantly in the lengths of their long fertilizing sperm, to test predictions about the relationship between sperm length and four mating system characters: male age at sexual maturity; sperm number; female remating; and male reproductive output. In D. affinis, where males produce the longest fertilizing sperm, their sexual maturity is delayed and they produce fewer long sperm compared to the other two species, as predicted if long sperm are costly to produce. Female D. affinis, although they receive fewer sperm than females of the other two species, do not remate more frequently or produce fewer progeny from a single mating. Different responses between sperm-heteromorphic and sperm-monomorphic systems underscore the complex nature of the coevolution between male and female mating system characters.     

Phylogenetic relationships of Drosophila melanogaster species group deduced from spacer regions of histone gene H2A-H2B

Nucleotide sequences of the spacer region of the histone gene H2A-H2B from 36 species of Drosophila melanogaster species group were determined. The phylogenetic trees were reconstructed with maximum parsimony, maximum likelihood, and Bayesian methods by using Drosophila pseudoobscura as the out group. Our results show that the melanogaster species group clustered in three main lineages: (1). montium subgroup; (2). ananassae subgroup; and (3). the seven oriental subgroups, among which the montium subgroup diverged first. In the third main lineage, suzukii and takahashii subgroups formed a clade, while eugracilis, melanogaster, elegans, ficusphila, and rhopaloa subgroups formed another clade. The bootstrap values at subgroup levels are high. The phylogenetic relationships of these species subgroups derived from our data are very different from those based on some other DNA data and morphology data.     

The phylogeny of the subgroups within the melanogaster species group: likelihood tests on COI and COII sequences and a Bayesian estimate of phylogeny

The relationships among the majority of the subgroups in the Drosophila melanogaster species group remain unresolved. We present a 2223basepair dataset for mitochondrial cytochrome oxidase I and cytochrome oxidase II for 43 species (including new data from 11 species), sampled to include the major subgroups. After a brief review of competing hypotheses for the ananassae, montium, suzukii, and takahashii subgroups, we combine the two genes based on a new use of the SH test and present KH and SH likelihood comparisons (Kishino and Hasegawa, 1989. J. Mol. Evol. 29, 170-179; Shimodaira and Hasegawa, 1999) to test the monophyly and placement of these subgroups within the larger species group. Although we find insignificant differences between the two suggested placements for the ananassae subgroup, the ananassae is sister to the rest of the subgroups in the melanogaster species group in every investigation. For the takahashii subgroup, although we cannot reject monophyly, the species are so closely related to the suzukii subgroup for these data that the two subgroups often form one clade. Finally, we present a Bayesian estimate of the phylogeny for both genes combined, utilizing a recently published method that allows for different models of evolution for different sites.     

Phylogenetic relationships and climatic adaptations in the Drosophila takahashii and montium species subgroups

We analyze phylogenetic relationships among temperate, subtropical highland, and subtropical lowland species of the Drosophila takahashii and montium species subgroups based on sequence data of COI and Gpdh genes and discuss the evolution of temperate species in these subgroups with reference to their climatic adaptations. In the takahashii subgroup, D. lutescens (the temperate species) branched off first in the tree based on the combined data set, but D. prostipennis (the subtropical highland species) branched off first in the trees based on single genes. Thus, phylogenetic relationships in this subgroup are still ambiguous. In the montium subgroup, the cool-temperate species are phylogenetically close to the warm-temperate species, and these cool- and warm-temperate species form a cluster with the subtropical highland species. This suggests that perhaps the cool-temperate species derived from the warm-temperate species and the warm-temperate species derived from the subtropical highland species. In comparison with the subtropical lowland species, the subtropical highland species may be better able to colonize temperate areas since, as in the temperate species, they have an ability to develop their ovaries at moderately low temperature. However, the subtropical highland species, as well as the subtropical lowland species, were much less cold tolerant than the temperate species. Therefore, considerable genetic reformation would be required for both the subtropical highland and the subtropical lowland species to adapt to temperate climates.     

Adaptive evolution of recently duplicated accessory gland protein genes in desert Drosophila

The relationship between animal mating system variation and patterns of protein polymorphism and divergence is poorly understood. Drosophila provides an excellent system for addressing this issue, as there is abundant interspecific mating system variation. For example, compared to D. melanogaster subgroup species, repleta group species have higher remating rates, delayed sexual maturity, and several other interesting differences. We previously showed that accessory gland protein genes (Acp's) of Drosophila mojavensis and D. arizonae evolve more rapidly than Acp's in the D. melanogaster subgroup and that adaptive Acp protein evolution is likely more common in D. mojavensis/D. arizonae than in D. melanogaster/D. simulans. These findings are consistent with the idea that greater postcopulatory selection results in more adaptive evolution of seminal fluid proteins in the repleta group flies. Here we report another interesting evolutionary difference between the repleta group and the D. melanogaster subgroup Acp's. Acp gene duplications are present in D. melanogaster, but their high sequence divergence indicates that the fixation rate of duplicated Acp's has been low in this lineage. Here we report that D. mojavensis and D. arizonae genomes contain several very young duplicated Acp's and that these Acp's have experienced very rapid, adaptive protein divergence. We propose that rapid remating of female desert Drosophila generates selection for continuous diversification of the male Acp complement to improve male fertilization potential. Thus, mating system variation may be associated with adaptive protein divergence as well as with duplication of Acp's in Drosophila.     

Isozyme Variation among Biological Species in the Gibberella fujikuroi Species Complex (Fusarium Section Liseola)

Isozyme phenotypes were determined for 101 strains of Gibberella fujikuroi and 2 strains of Gibberella nygamai that represent seven biological species (mating populations) isolated from a variety of plant hosts in dispersed geographic locations. Fourteen enzymes were resolved in one or more of three buffer systems. Two of the enzymes, arylesterase and acid phosphatase, were polymorphic within two or more biological species and are suitable for intraspecific studies of population variation. Six enzymes, alcohol dehydrogenase, aspartate aminotransferase, glucose-6-phosphate dehydrogenase, mannitol dehydrogenase, phosphoglucomutase, and phosphogluconate dehydrogenase, were monomorphic in all of the isolates examined. The remaining six enzymes, fumarase, glucose phosphate isomerase, glutamate dehydrogenase (NADP), isocitrate dehydrogenase (NADP), malate dehydrogenase, and triose-phosphate isomerase, could potentially be used to distinguish the different biological species. Mating populations C and D are the most similar, since the mating population C isolates examined had the same isozyme phenotype as did a subset of the isolates in mating population D. Mating population E is the least similar to the other taxa examined. Unique isozyme phenotypes are present but are composed of banding patterns shared among the biological species. This finding supports the hypothesis that these biological species, with the possible exception of mating populations C and D, are reproductively isolated from one another and that no significant gene flow is occurring between them. Isozyme analysis is a useful method to distinguish these closely related biological species. Examination of isozyme phenotypes is more rapid than the present technique, which is based on sexual crosses; can be applied to strains that are not sexually fertile; and is more sensitive than traditional morphological characters, which cannot distinguish more than three or four morphological groups among the seven biological species. While emphasizing the discreteness of the mating populations as biological entities, our isozyme data also reaffirm the close genetic relationship among these groups.