Q95237977
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The circadian transcription of the tim gene is tightly regulated by the protein complex dCLK/CYC, which directly interacts with a series of closely spaced E-box and E-box-like elements in the Drosophila timeless promoter. The tim promoter from D. melanogaster has been studied in detail both in tissue cultures and in living flies yet has never been investigated in other species. This article presents a detailed functional analysis of the tim promoter from the drosophilid fly, Chymomyza costata, in Drosophila tissue cultures. A comparison of tim promoters from wt and npd-mutants confirmed that the 1855 bp deletion in the latter removes crucial regulatory cis-elements as well as the minimal promoter, being subsequently responsible for the lack of tim mRNA expression. Deletion and substitution mutations of the wt tim promoter showed that the region containing the canonical E-box, TER-box, and 2 incomplete E-box sequences is essential for CLK/CYC-mediated expression, while the PERR element appears to be a repressor in S2 cells. Furthermore, the expression of the circadian genes timeless, period , vrille, and doubletime was quantified in C. costata adults. Striking differences were found in expression profiles for tim, per, and vri between wild-type and npd-mutant individuals.
- MeSH
- buněčné linie MeSH
- cirkadiánní hodiny genetika MeSH
- Drosophila melanogaster cytologie genetika MeSH
- Drosophilidae genetika MeSH
- druhová specificita MeSH
- elementy E-Box genetika MeSH
- genetická transkripce MeSH
- hmyzí proteiny genetika MeSH
- molekulární sekvence - údaje MeSH
- mutace MeSH
- promotorové oblasti (genetika) genetika MeSH
- proteiny Drosophily genetika MeSH
- sekvence nukleotidů MeSH
- sekvenční homologie nukleových kyselin MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Current models state that insect peripheral oscillators are directly responsive to light, while mammalian peripheral clock genes are coordinated by a master clock in the brain via intermediate factors, possibly hormonal. We show that the expression levels of two circadian clock genes, period (per) and Par Domain Protein 1 (Pdp1) in the peripheral tissue of an insect model species, the linden bug Pyrrhocoris apterus, are inversely affected by contrasting photoperiods. The effect of photoperiod on per and Pdp1 mRNA levels was found to be mediated by the corpus allatum, an endocrine gland producing juvenile hormone. Our results provide the first experimental evidence for the effect of an endocrine gland on circadian clock gene expression in insects.
- MeSH
- cirkadiánní rytmus MeSH
- endokrinní systém MeSH
- financování organizované MeSH
- Heteroptera genetika MeSH
- jaderné proteiny genetika MeSH
- regulace genové exprese genetika MeSH
- trans-aktivátory genetika MeSH
- transkripční faktory bZIP genetika MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH