Experiments on sexual isolation between Chilean and European strains ofDrosophila subobscura

Summary Males and females of Chilean strains ofDrosophila subobscura exhibit a pronounced tendency toward homogamic mating. This tendency shows a clear relation to the distance between the geographic localities from which the respective strains came. Nevertheless, when the Chilean flies are confronted with European strains, the ethological isolation is observed in some cases but not in others, depending on the geographic origin of the strains.Acknowledgments. This work has been partially supported by grants from the Univ. of Chile (Project B 729-8345) and PNUD/UNESCO (RLA 78/024). We are most grateful to Prof. D. Sperlich of the University of Tübingen who provided theD. subobscura strains from Tübingen and Sicily, and Prof. A. Prevosti from the University of Barcelona and R. de Frutos from the University of Valencia who provided the strains of Mallorca and Almería. We are finally obliged to Mr E. Zárate for his technical assistance.     

The ovicidal activity ofcis-dehydromatricaria ester: time-dependance of its enhancement by UV light

Summary Freshly laid eggs ofDrosophila melanogaster were treated with the polyacetylenic compoundcis-dehydromatricaria ester. The toxicity of the chemical was enhanced by treatments with long-wavelength ultraviolet light, and the maximum effect was observed when the UV irradiation was performed 4–5 h after the initial contact of the eggs with the chemical.We are grateful to Professor E. Spiess for advice and assistance, and to the National Institutes of Health (GM 24144) for financial support.     

基于S2细胞建立钙库调控钙离子通道特异分子的筛选模型

应用Flexstation胞质溶胶钙离子检测技术,研究利用果蝇S2细胞建立钙库调控钙离子通道SOC的特异分子的筛选模型.通过三种已知钙通道拮抗剂的检测,发现培养温度为24℃,细胞密度为2×106个/mL时,利用终浓度为2μmol/L的SOC通道激动剂TG可建立稳定的细胞筛选模型.     

Axon guidance at the central nervous system midline

A key feature of the central nervous system of most higher organisms is their bilateral symmetry about the midline. The specialised cells that lie at the midline have an essential role in regulating the axon guidance decisions of both neurons that project axons across the midline and those that project on one side. The midline cells produce both attractive and repellent short- and long-range signals to guide axonal growth. The axons themselves express specific receptors that can be dynamically regulated in response to midline-derived signals. In this way, axons extend toward or away from the midline and those that do cross change their behaviour to respond to longitudinal signals on the contralateral side.     

紫甘薯提取物对果蝇的紫外辐射保护作用

研究紫外线诱导后(20,W紫外灯下照射40,min)紫甘薯提取物对果蝇辐射损伤的保护作用.在紫外线氧化损伤果蝇模型中添加紫甘薯提取物后,果蝇寿命显著提高,且有剂量依赖性.紫甘薯提取物提高了紫外线氧化损伤果蝇体内的超氧化物歧化酶(SOD)比活力和过氧化氢酶(CAT)比活力,降低了丙二醛(MDA)水平.说明紫甘薯提取物具有抗氧化损伤、延缓衰老的作用,为紫甘薯提取物更好地应用于营养食品、保健食品中提供理论依据.     

培养果蝇的最佳生态因子研究

研究了饲养空间、温度、光照和饲料成分等生态因子对野生型黑腹果蝇发育和繁殖的影响.结果表明:除光照时间外,其他因子对果蝇的生长、繁殖都有明显的影响.果蝇繁殖的子代数量随饲养空间的增大而增加,最适培养温度为25~28℃,饲料中酵母粉最适用量为常规用量的3~4倍,糖含量高或低都不利于果蝇的发育和繁殖.     

果蝇分子群体遗传研究分析方法概述

果蝇属物种长期以来被作为基础生物学、特别是群体和进化遗传学的模式物种,来探讨生物学中的一些基本问题,如物种形成的遗传机制、新基因的起源及其方式、适应性进化的遗传机制等.群体遗传的方法贯穿于遗传学、生态学、古生物学、系统发育学等领域之中,已渐成为基础生物学研究的重要方法.围绕果蝇群体遗传研究中的3个主要问题,即起源地、群体历史动态和群体遗传结构,就当前用于分析上述问题的方法进行了概述,并强调了发展适用于多个座位数据的分析方法是将来的一个重要发展方向.     

苯甲酸对果蝇生长发育的影响

研究不同浓度的苯甲酸对果蝇生长发育的影响.采用野生型的果蝇,分别喂饲含有不同浓度的苯甲酸（浓度分别为0.05%,0.10%,0.15%）的培养基,记录F1代的数目.不同浓度的苯甲酸组与对照组比较,随着苯甲酸浓度的增大,对果蝇的成蛹时间、羽化时间延长,体重减轻,F1代数量减少.结论：苯甲酸对果蝇的生长发育有着明显的抑制作用.     

Genetic load and effective size of natural populations ofDrosophila melanogaster in Korea

Summary The effect of 750 second chromosomes ofDrosophila melanogaster on viability was studied. 19.3% of them proved letal or semilethal (=drastics) in homozygous condition. Compared to data obtained in previous years at the same sampling site, a significant frequency decrease of drastics during the past decade could be observed. The dynamic processes taking place in the Korean wild populations ofD. melanogaster are discussed.Acknowledgment. This work was supported by a research grant from the Korean Science and Engineering Foundation.