title: Functional analysis of the circadian clock gene timeless in Tribolium castaneum.
abstract: Circadian rhythms are endogenous oscillations with a period of about 24 h driven by a circadian clock. So far, variable oscillators have been found in insects. To explore the circadian clock of Tribolium castaneum, we cloned the clock gene timeless (Tctimeless). Its open reading frame is 3240 bp in length and consists of 10 exons. Tctimeless is highly expressed in the late pupal stage. Tissue-specific expression analysis in late adult stages revealed high expression of Tctimeless in the head, epidermis, fat body and accessory glands. Silencing of Tctimeless by RNA interference (RNAi) at the late larval stages caused a failure to initiate eclosion. Tctimeless knockdown in late pupal stages led to a gender-independent decline in egg production and progeny survival. As a core clock gene, Tctimeless exhibited one expression peak in the middle of the circadian day. Knockdown of Tctimeless disrupted daily expression patterns of Tccycle, Tcclock, Tcperiod and itself, while Tctimeless and Tcperiod expression patterns over the circadian day were also perturbed when Tccycle or Tcclock is suppressed by RNAi. This study identified a complex transcriptional relationship among circadian clock genes in T. castaneum.
authors.affiliation: Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China.|Institute of Life Sciences, School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China.
authors.forename: Cheng-Jun
authors.initials: CJ
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China.
authors.forename: Xiao-Pei
authors.initials: XP
authors.lastname: Yun
authors.affiliation: Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China.
authors.forename: Xiao-Juan
authors.initials: XJ
authors.lastname: Yu
authors.affiliation: Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Li
mesh_terms: D000818:Animals; D056926:CLOCK Proteins / Q000235:genetics* / Q000378:metabolism; D057906:Circadian Clocks / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D056950:Period Circadian Proteins / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D034622:RNA Interference; D014231:Tribolium / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D019476:Insect Proteins; D056950:Period Circadian Proteins; D056926:CLOCK Proteins
keywords: circadian rhythms; clock; cycle; eclosion; reproduction; timeless