TIMELESS: A link between fly's circadian and photoperiodic clocks?
By J. Pavelka, K. Shimada, V. Košťál. 2003
89 citations recorded by the source corpus.
Potential involvement of circadian clock genes in so far unknown mechanism of photoperiodic time measurement is an important question of insect life-cycle regulation science. Here we report about the cloning of full-length cDNA of the structural homologue of the Drosophila's timeless gene in Chymomyza costata. Its expression was compared in two strains: a wild-type strain, responding to short days by entering larval diapause and a npd-mutant strain, showing no photoperiodic response. The timeless mRNA transcripts were not detectable by Northern blot analysis in the fly heads of npd-mutants, while they were detectable and showed typical daily oscillations in the wild-type strain. After disrupting the normal process of timeless transcription in the wild-type strain by injection of timeless double-strandRNA into early embryos of wild-type (RNAi method: Kennerdell & Carthew 1998, 2000), a certain proportion of the individuals adopted a npd-mutant phenotype, showing no-diapause in response to short-daylength. Cloning of genomic DNA fragments revealed that npd-mutants carry a different allele, timelessnpd, with a 13-bp insertion in an intron positioned within the 5'-leader sequence. Genetic linkage analysis showed that the 13-bp insertion (a marker for timelessnpd) and the absence of response to short days (a marker for npd-phenotype) are strictly co-inherited in the F2 progeny of the reciprocal crosses between wild-type and npd-mutant flies. Such results indicated that the locus npd could code for the timeless gene in C. costata and its product might thus represent a molecular link between circadian and photoperiodic clock systems in this fly.
Subfields: Aging, Endocrine and Autonomic Systems, Plant Science
View Paper: https://www.semanticscholar.org/paper/4db6d1084a4c370e18fc5b3e58fdc1c07c84b712
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In Aging
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Citations in the corpus
- Eco-physiological phases of insect diapause. (2006, background): “…clock proteins with influnce on diapause induction (Saunders et al., 1989; Shimada, 1999; Kosˇtaí and Shimada, 2001; Goto and Denlinger, 2002a; Pavelka et al., 2003; Hodkovaét al., 2003; Syrovaét al., 2003; Spieth et al., 2004; Dolezěl et al., 2005), or (e) with some other functions (Lee…”
- Roles of circadian clock genes in insect photoperiodism (2013, background): “The tim mRNA is barely detectable in npd-mutant flies (Pavelka et al. 2003; Stehlík et al. 2008).”