›› 2005, Vol. 48 ›› Issue (4): 473-482.

• 研究论文 •    下一篇


G. MITROFANOV,薛东,杨长举,姚英娟,蔡万伦   

  • 出版日期:2005-09-07 发布日期:2005-08-20
  • 通讯作者: 薛东

Temperature sensitive periods and autonomy of pleiotropic effects of dlts, a conditional discless lethal mutation in Drosophila virilis

Vladimir G. MITROFANOV, XUE Dong, YANG Chang-Ju,YAO Ying-Juan, CAI Wan-Lun   

  • Online:2005-09-07 Published:2005-08-20

摘要: 本文采用D.T.Suzuki的方法,研究了黑果蝇Drosophila virilis Sturt dlts品系的温度敏感时期和致死时期的相互关系。选择了31℃为限制温度,25℃为许可温度。对于成虫盘缺损的研究用了12个小时为一个脉冲或24个小时为一个脉冲的热处理,用扫描电镜技术辅助对成虫形态缺损的研究。对于成虫盘缺失和重复的关系主要在48小时为一个脉冲的热处理盘中进行,对dlts基因的表达采用了遗传嵌合性的研究,其结果如下:1两个不连续的温度敏感时态对致死的影响是在第1龄幼虫、第2龄幼虫、第3龄幼虫和进入蛹期后的10个小时。温度敏感时态和致死时态并不一致,而是先于致死时态几个小时。2温度敏感时态对成虫形态的影响是:触角的重复和复眼的缺失发生在第2龄和第3龄幼虫期。足关节融合及跗节和腿节的缩短发生在第3龄幼虫期,翅脉硬化主要发生在第3龄幼虫期即将结束进入前蛹期的这段时间。第3龄幼虫期是成虫盘发生缺陷比较集中的时期,可以明显见到足、复眼、翅和刚毛的缺陷,同源异型突变体也在这个时期发生。同源突变体的变化主要是足、触角片段及刚毛和触角片段的相互转移。3每一个成虫盘缺陷部有自己明显的特征,根据它们成虫盘的形态缺陷和热处理的时间性,所有的成虫盘缺陷变化都可以分为这样三类:缺失,重复,缺失和重复并存。4遗传镶嵌测试表明:dlts基因是自主表达的,且具有一定的时间、环境和组织的特殊性。

关键词: 黑果蝇, 成虫盘, 温度敏感时态, 致死时态, 模式结构


A series of temperature shift experiments have been conducted with homo and/or hemizygous strains for temperature sensitive (ts) mutations of the discless, dlts in Drosophila virilis Sturt, where the restrictive temperature is 31℃, and the permissive temperature is 25℃. The temperature threshold is set at 29℃ and fluctuates between 25℃ and 31℃ at an interval of 2℃. The temperaturesensitive period (TSP) is determined by the analysis of both shift up and shift down experiments. Discrete TSPs for lethality are localized on the first, the second and the third larval instar for a 10 hr period after pupation with an interval of a few hours between TSP and the lethal phase (LP). TSPs for adult morphology defects are localized on the second, the third larval instars and the early pupal period. Animals during TSPs are subjected to 12 hr pulse, 24 hr pulse, and 48 hr pulse treatments respectively, and have produced a large number of defects. The defects include: eye scar, clumping pigment eye, small and lozenge shaped eye, missing facets, small wing, thick wing vein, shortened tarsal segments, fused leg segments, extra macrochaetae or bristles, missing antennal segments, and duplicating palpus and/or lacinia, with distinct patterns of eye, wing, bristle and leg defects observed within the third larval instar. Homoeotic mutants also occur in this period. Each defect has its own specific timedependent pattern. The patterns of damage are observed in imaginal tissue and all the defects are categorized into three classes: repeat, deletion and repeat and deletion happened at the same time. There is evidence from genetic somatics that there are some specific time patterns for dlts to produce the pleiotropic effects.

Key words: Drosophila virilis, imaginal disc, temperaturesensitive period, lethal phase, pattern formation