Taxonomic identification of Drosophila nasuta subgroup strains by glue protein analysis

Protein fractions of salivary glands were analyzed from 30 wildtype strains of eight species belonging to the Drosophila nasuta subgroup by SDS-polyacrylamide gel electrophoresis. The electrophoretic patterns indicated several prominent bands which could be shown to represent the major glue protein fractions. The glue protein fractions are species-specific as well as wildtype strain-specific. Wildtype strain specificities are characterized by variations of the species-specific patterns. The patterns of the different wildtypes, species, and hybrids were used for taxonomic identification within the nasuta subgroup, in which the females are morphologically indistinguishable and the males differ only by the markings of their frons. The hybrids provide evidence for gonosomal as well as autosomal linkage of individual genes coding for the major glue protein fractions.     

Comparative analysis of glue proteins in theDrosophila nasuta subgroup

The patterns of protein fractions from total salivary glands and from glue plugs were compared in seven members of the Drosophila nasuta subgroup by the use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The glue protein patterns are member specific concerning the numbers and the electrophoretic mobilities of major and minor glue protein fractions. However, the major fractions of all subgroup members could be grouped into five SDS-PAGE domains according to the homologies of their electrophoretic mobilities, prominence of Coomassie blue staining, and PAS reaction. In all subgroup members, major fractions are involved in posttranslational modifications into larger protein molecules of the final glue. Quantitative estimations of the glue proteins in D. n. nasuta and D. n. albomicans reveal that they constitute between 55 and 60% of the total salivary gland proteins, whereas in D. melanogaster and in D. hydei the fraction is only 32 and 35%, respectively.     

Introgressive hybridization and evolution of a novel protein phenotype: Glue protein profiles in thenasuta-albomicans complex ofDrosophila

Glue proteins are tissue-specific proteins synthesized by larval salivary gland cells ofDrosophila. InDrosophila nasuta nasuta andD. n. albomicans of thenasuta subgroup, the genes that encode the major glue protein fractions are X-linked. In the present study, these X-linked markers have been employed to trace the pattern of introgression ofD. n. nasuta andD. n. albomicans genomes with respect to the major glue protein fractions in their interracial hybrids, called cytoraces. These cytoraces have inherited the chromosomes of both parents and have been maintained in the laboratory for over 400–550 generations. The analysis has revealed that cytoraces withD. n. albomicans X chromosome show eitherD. n. nasuta pattern or a completely novel pattern of glue protein fractions. Further, quantitative analysis also shows lack of correlation between the chromosomal pattern of inheritance and overall quantity of the major glue protein fractions in the cytoraces. Thus, in cytoraces the parental chromosomes are not just differentially represented but there is evidence for introgression even at the gene level.     

Male accessory gland secretory proteins in nasuta subgroup of Drosophila: nature and SDS-PAGE patterns

Male accessory gland secretory proteins in seven members of Drosophila nasuta subgroup were analyzed by SDS-PAGE in combination with different staining techniques such as CBB-R250, Silver, PAS, PAS-silver and zinc-imidazole reverse staining. Based on coomassie blue patterns the protein fractions could be classified in to 3 major groups namely group I, group II as well as group III; with high molecular weight fractions falling into group I and low molecular weight fractions into group III. All the three groups of fractions are post-translationally modified by way of glycosylation and group III fractions are found to be highly glycosylated. Fractions of groups I and II when localized with silver stain and group III fractions when localized with PAS-silver stain appear yellow; suggesting that they are sialoglycoproteins. A 40 kD fraction of group II shows differential staining property with zinc-imidazole stain in closely related species namely D. n. nasuta and D. n. albomicans. Analysis of this protein fraction in F1 males of an interspecific cross revealed that it is synthesized by X-chromosomal gene.     

Glue proteins inDrosophila nasuta

Larval glue protein fractions ofDrosophila nasuta nasuta were analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Seven major and at least four minor glue protein fractions were recognized. Six of the major fractions are glycosylated. They migrate as three prominent doublets (>100, 43, and 30/28 kd). The synthesis of traceable amounts of these major fractions begins already during the second as well as during the early stages of the third larval instar. The 43-kd and the 30/28-kd fractions are coded by X-chromosomal genes. They are probably clustered within the huge puff of division 10, which is the most prominent X-chromosomal puff in the polytene chromosomes of the third larval instar. Complex posttranslational modification of all but one major glue protein fraction (14 kd) leads to the formation of about 15 different protein fractions in the final glue product. The amount of glue protein produced byD. n. nasuta larvae (in relation to the total saliva proteins) is nearly twice the amount produced byD. melanogaster larvae (ca. 55 and 32%, respectively). This work was supported by the University Grants Commission, New Delhi, India, the Deutscher Akademischer Austauschdienst, FR Germany (to S.R.R.), and the Deutsche Forschungsgemeinschaft (Ka 309/9-1).     

Male accessory gland secretory proteins in a few members of the Drosophila nasuta subgroup

Male accessory gland secretory proteins in seven members of the Drosophila nasuta subgroup have been analyzed by SDS-PAGE. The study revealed remarkable simplicity in the patterns. The protein fractions, which migrate in three groups, could be categorized as major and minor. The number of major fractions varies from a maximum of eight to a minimum of four. Group I consists of high molecular weight fractions, and group III, low molecular weight fractions. Among different members analyzed, the variation with respect to pattern and the number of fractions are confined largely to group III protein fractions, while group I and II fractions are found to be conserved to a greater extent. These proteins are PAS positive and group III fractions are not sensitive to silver staining. Analysis of these tissue specific proteins in the F₁ and F₂ of interspecific crosses and backcross progeny as well as volume analysis revealed that a 26-kD fraction in D. n. nasuta follows an autosomal pattern of inheritance, while a 55-kD and a 25-kD fraction in D. n. albomicans and a 24-kD fraction in D. n. kepulauana follow an X-linked pattern of inheritance.     

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。     

Molecular phylogeny of the nasuta subgroup of Drosophila based on 12S rRNA, 16S rRNA and CoI mitochondrial genes, RAPD and ISSR polymorphisms

The nasuta subgroup is a cluster of morphologically almost similar forms with a wide range of geographic distribution. During the last three decades nature of inter-relationship among the members has been investigated at different levels of organization. The phylogenetic relationships of the members of the nasuta subgroup of the immigrans species group of Drosophila was made by employing Random Amplified Polymorphic DNA (RAPD), Inter Simple Sequence Repeats-PCR (ISSR-PCR) polymorphisms, mitochondrial 12S rRNA, 16S rRNA and Cytochrome C Oxidase subunit I (CoI) gene sequences. The phylogenetic tree generated by RAPD analysis is in nearly complete congruence with the classification based on morphophenotypic characters. The 12S and 16S rRNA genes were highly conserved across the nasuta subgroup and revealed only 3 and 4 variable sites respectively, of which only one site was informative. The CoI gene, on the other hand, revealed 57 variable sites of which 25 sites were informative. All the three species of orbital sheen complex were included in a major cluster in the phylogenetic trees derived from mitochondrial gene sequence data consistent with the morphophenotypic classification. The CoI analysis placed two species of frontal sheen complex, D. n. nasuta and D. n. albomicans in two different clades and this is inconsistent with morphological classification. The molecular clock suggested that divergence between the kohkoa complex and the albomicans complex occurred approximately 2.2 MYA, indicating recent evolution of the nasuta subgroup. The higher transition bias in the mitochondrial genes reported in the present study also suggested recent evolution of the nasuta subgroup.     

伊米果蝇种组（Drosophila immigrans species group）H2a-H2b和Cyt b分子系统发育关系（简报）

伊米果蝇种组(Drosophila immigrans speciesgroup)是果蝇科(Drosophilidae)、果蝇属(Drosophi-la)、果蝇亚属(Drosophila)中数量最多的一个类群,主要分布于东洋区。在分类学上该种组分为nasuta、immigrans、hypocausta、quadrilineata和curviceps五个种亚组(species subgroup)[1],东洋区果蝇区系中伊米果蝇种组中包括94个种,其中有45个种分布在中国[2]。而且curviceps种亚组是1992年新建立的中国特有果蝇类群[3]。迄今,对伊米果蝇种组分子系统关系的报道还很少,有些物种的归属仍存在争议。伊米果蝇种组还有些问题需要探讨[4]。组蛋白基因…     

The speciation history of the Drosophila nasuta complex

The Drosophila nasuta subgroup of the immigrans species group is widely distributed throughout the South-East Asian region, consisting of morphologically similar species with varying degrees of reproductive isolation. Here, I report nucleotide variability data for five X-linked and two mtDNA loci in eight taxa from the nasuta subgroup, with deeper sampling from D. albomicans and its sister species D. nasuta. Phylogenetic relationships among these species vary among different genomic regions, and levels of genetic differentiation suggest that this species group diversified only about one million years ago. D. albomicans and D. nasuta share nucleotide polymorphisms and are distinguished by relatively few fixed differences. Patterns of genetic differentiation between this species pair are compatible with a simple isolation model with no gene flow. Nucleotide variability levels of species in the nasuta group are comparable to those in members of the melanogaster and pseudoobscura species groups, indicating effective population sizes on the order of several million. Population genetic analyses reveal that summaries of the frequency distribution of neutral polymorphisms in both D. albomicans and D. nasuta generally fit the assumptions of the standard neutral model. D. albomicans is of particular interest for evolutionary studies because of its recently formed neo-sex chromosomes, and our phylogenetic and population genetic analyses suggest that it might be an ideal model to study the very early stages of Y chromosome evolution.     

Comparative examination of soluble red muscle proteins of fifteen Sparidae species

Soluble red muscle proteins from the lateral line of 15 Sparidae species were analysed by isoelectric focusing. Species-specific patterns were found. The species-specific protein fractions could be correlated with different metabolic activities and with different growth indexes. More protein fractions were identified for Pagellus acarne (Risso) and Diplodus annularis (L.) than for the other 13 species. This would appear to be related to growth index. The existence of red muscle with a greater number of protein bands than white muscle was confirmed in almost all species. The similarity coefficients have shown that closely related species have similar patterns and, thus, higher similarity coefficients. The derived dendrogram agrees with previous classifications based on morphological information.     

Metaphase chromosomes of four species of the Drosophila nasuta subgroup

Metaphase chromosomes of four species of the Drosophila nasuta subgroup, D. nasuta, D. kepulauana, D. kohkoa, and D. neveifrons, were analysed by the C banding method to clarify the chromosomal differentiation during speciation. Four species were different in heterochromatic regions of their chromosomes, especially microchromosomes of the fourth chromosomes and the Y chromosomes. Intraspecific variations of heterochromatic regions were also found among isofemale lines from various localities of D. nasuta, D. kepulauana, and D. kohkoa. Intraspecific variations of heterochromatic regions were not different from interspecific variations morphologically. From these results, the evolutionary process of heterochromatic regions was discussed.     

Circular DNA Molecules in the Genus Drosophila

The satellite DNA's from the embryos of five species of Drosophila (D. melanogaster, D. simulans, D. nasuta, D. virilis and D. hydei) have been analyzed for the presence of closed circular duplex DNA molecules, as determined by CsCl-EBr gradients. Circular DNA molecules were found in every species but D. melanogaster. Analyses of cell fractions from adult Drosophila and organ fractions from Drosophila larvae show that fractions containing mitochondria are highly enriched in these molecules.     

果蝇Drosophila nasuta亚群系统发育问题的探讨

果蝇Ｄｒｏｓｏｐｈｉｌａｎａｓｕｔａ亚群由在１４个处于不同物种分化阶段的种,亚种和分类元组成,这个亚群的物种有许多进化上的独特之处,使得它在物种分化研究方面倍受关注,然而,在形态学,生殖隔离,染色体和同工酶多态,线粒体ＤＮＡＲＦＬＰ,求偶歌特征惟及线粒体和核基因序列分析等方面的研究都未能清楚地阐明这一亚群的系统进化关系,本文综合分析了关于这一亚群的进化遗传学的研究结果,并提出了有待进一步的一些问题     

Influence of mating histories and age on female remating behaviour in a few closely related species of Drosophila nasuta subgroup

Female remating with more than one male leads to coexistence of sperm from different males in the same female, thus creating a selection pressure on sperm. To understand the extent of divergence in the reproductive behaviour among closely related species, in the present study, the influence of first mating histories like mating latency, duration of copulation and age of flies have been analysed on female remating behaviour in closely related Drosophila nasuta subgroup species with varying levels of reproductive isolation. The time taken for the once mated females to remate varied from 7 days in D. s. sulfurigaster to 19 days in D. s. neonasuta after first mating. The female remating frequency varied from a minimum of 29% in D. s. neonasuta to a maximum of 95% in D. s. sulfurigaster. The younger flies, which had remating latency of three times less than aged flies, show 100% remating frequency. In addition, it was observed that the duration of copulation in the first mating influences the remating behaviour among the nasuta subgroup members. The results revealed that D. nasuta subgroup members despite being closely related differ in their reproductive behaviour.     

Interspecific hybridization in Daphnia: distinction and origin of hybrid matrilines

Three coexisting Daphnia species belonging to the D. longispina group (D. galeata, D. hyalina, and D. cucullata) form species-hybrid complexes by producing interspecific hybrids in several lakes in Germany and The Netherlands. To evaluate the genetic consequences of interspecific hybridization, I studied the patterns of mitochondrial DNA (mtDNA) sequence variation. The directionality of interspecific hybridization and divergence of hybrids from parental species was tested, using the DNA sequences of a segment of mtDNA. Via the polymerase chain reaction, it was possible to investigate single animals and even single resting eggs. A species-specific marker was established, using restriction patterns of amplified cytochrome b segments. mtDNA genotypes of hybrids revealed unidirectional mitochondrial gene flow for two hybrids, which were investigated by using multiple clones. No evidence for introgression of mtDNA was found. On the basis of a phylogenetic analysis, the species exhibit considerable distinctness, whereas differences between clones within species and between hybrids and maternal species tend to be very low. These results indicate a recent origin of hybrids and suggest that the radiation of the D. longispina group occurred > 5 Mya.      

Hybridization and introgression of the genomes of Drosophila nasuta and Drosophila albomicans: evolution of new karyotypes.

Drosophila nasuta (2n = 8) and Drosophila albomicans (2n = 6) are cross-fertile allopatric sibling chromosomal races of the nasuta subgroup of Drosophila. Hybrids of these races can be maintained for any number of generations. Some of the introgressed hybrid lineages of D. nasuta and D. albomicans, after passing through a transient phase of karyotypic polymorphism, ended up with a stable karyotype whose composition is different from those of the parental races. Such hybrid populations were called cytoraces, in which the chromosomes of D. nasuta and D. albomicans are represented in different combinations. The karyotypic composition of 16 such cytoraces have been presented and discussed with reference to evolutionary strategies such as balancing selection, directional selection, and sex-specific effect on different components of the evolving karyotypes.     

Male accessory gland secretory protein polymorphism in natural populations of <Emphasis Type="Italic">Drosophila nasuta nasuta</Emphasis> and <Emphasis Type="Italic">Drosophila sulfurigaster neonasuta</Emphasis>

Male accessory gland secretory protein polymorphism was analysed in natural populations of Drosophila nasuta nasuta and D. sulfurigaster neonasuta for the first time, using SDS-PAGE to score polymorphism of these proteins in 2788 individuals of D. n. nasuta and 2232 individuals of D. s. neonasuta from 12 different populations from southern India. A total of 25 and 18 variant protein phenotypes were identified in D. n. nasuta and D. s. neonasuta, respectively. Protein fractions of group III were more polymorphic than those from groups I and II. The results show that accessory gland secretory proteins show high levels of polymorphism, irrespective of species or habitat. Moreover, we have used the variation in the accessory gland proteins to assess the extent of divergence between the species and to infer their population structure. The study suggests that though both D. n. nasuta and D. s. neonasuta belong to the same subgroup, they differ in population structure, as far as accessory gland protein polymorphism is concerned.     

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