AN ULTRASHORT CLOCK MUTATION AT THE PERIOD LOCUS OF DROSOPHILA-MELANOGASTER THAT REVEALS SOME NEW FEATURES OF THE FLYS CIRCADIAN SYSTEM
AN ULTRASHORT CLOCK MUTATION AT THE PERIOD LOCUS OF DROSOPHILA-MELANOGASTER THAT REVEALS SOME NEW FEATURES OF THE FLYS CIRCADIAN SYSTEM
复制标题
DOI：
10.1177/074873049400900303
复制
发表时间：
1994-12-01
影响因子：
3.5
通讯作者：
HALL, JC
中科院分区：
文献类型：
--
作者：
KONOPKA, RJ;HAMBLENCOYLE, MJ;HALL, JC
通过化学诱变诱导黑腹果蝇的节律突变体，并通过测试运动活动节律分离，在新的变体中，其周期约为16小时。当与正常X染色体杂合时，导致这种超短周期的性连锁突变导致20小时节律。尽管有这种半显性现象，但新的突变被发现是周期（per）基因的等位基因，它与per-无效变异体不互补，从某种意义上说，对于per（T）（超快时钟等位基因）和per（-）杂合子的女性，其周期比per（T）/+的情况短得多。这些测试也比以前的情况更清楚地表明，每个突变两次“剂量”的快时钟导致的时间比一次剂量的女性所表现出的时间要短得多，而女性的另一个等位基因是功能丧失的变体。在光暗循环（LD 12：12）中，在基因型条件下携带per（T）的死亡导致比正常快8小时的自由运行期，但通过每天相移大量的小时数而夹带;然而，运动活动的晚上高峰比正常早许多小时。使用一种新开发的用于自动监测果蝇羽化的装置表明，per（T）在25 ℃时表现出非常边缘的羽化节律，但在25 ℃时表现出大约2.5 ℃的周期性。17-18小时，19度。在per（T）与正常pharate成人切片中的per编码蛋白（PER）的染色首次揭示了在野生型中以类似于先前在成人中证明的PER节律的方式化学检测到的信号强度周期。表达per（T）的pharate成虫的染色周期与野生型不同。发现per（T）的成年活动节律的温度补偿是错误的，因为当苍蝇被加热时，周期明显变短。然而，突变体表现出正常程度的延长期时，其自发活动进行监测，在重水的存在下。per（T）突变与dusky基因座的长周期Andante等位基因以异常的方式相互作用（与dy（And）与per（+）或另一个短周期per突变的相互作用相比）。这一点和其他独特的功能，每（T）的新突变的启发式价值的观点进行了讨论，包括可能会刺激更深入地了解周期基因的行动在分子水平上。
A rhythm mutant of Drosophila melanogaster was induced by chemical mutagenesis and isolated by testing for locomotor activity rhythms, which in the new variant had periods of approximately 16 hr. The sex-linked mutation responsible for this ultrashort period causes 20-hr rhythms when heterozygous with a normal X. This semidominance notwithstanding, the new mutation was revealed to be an allele of the period (per) gene by noncomplementation with per-null variants, in the sense that females heterozygous for per(T) (as the ultrafast-clock allele is called) and per(-) exhibited periods that were much shorter than in the case of per(T)/+. These tests also revealed in a clearer manner than in previous cases that two ''doses'' of a fast-clock per mutation lead to appreciably shorter periods than those exhibited by one-dose females whose other per allele is a loss-of-function variant. In light-dark cycles (LD 12:12), dies carrying per(T) in a genotypic condition leading to free-running periods that are 8 hr faster than normal nevertheless entrained, by phase-shifting that large number of hours each day; the evening peak of locomotor activity was, however, many hours earlier than normal. The use of a newly developed device for monitoring Drosophila eclosion automatically showed that per(T) exhibits a very marginal emergence rhythm at 25 degrees C, but periodicity of ca. 17-18 hr at 19 degrees. Staining of the per-encoded protein (PER) in sections of per(T) versus normal pharate adults revealed for the first time that the immunohistochemically detected signal cycles in its intensity in wild-type, in a manner that is similar to the PER rhythm previously demonstrated in adults. The staining cycle in pharate adults expressing per(T) differed from that of wild-type. Temperature compensation of the adult activity rhythm of per(T) was found to be faulty, in that periods became appreciably shorter as the flies were heated. However, the mutant exhibited a normal degree of period lengthening when its locomotor activity was monitored in the presence of heavy water. The per(T) mutation interacted with the long-period Andante allele of the dusky locus in a manner that was anomalous (in comparison to dy(And) interactions with per(+) or another short-period per mutation). This and other unique features of per(T) are discussed from the standpoint of the new mutation's heuristic value, including that which may stimulate a deeper understanding of the period gene's action at the molecular level.