Developmental Timing in C. elegans Is Regulated by kin-20 and tim-1, Homologs of Core Circadian Clock Genes

• Published in: Developmental cell 2005-02, Vol.8 (2), p.287-295
• Main Authors: Banerjee, Diya, Kwok, Alvin, Lin, Shin-Yi, Slack, Frank J.
• Format: Article
• Language: English
• Subjects: Animals; Animals, Genetically Modified; Biological and medical sciences; Caenorhabditis elegans; Caenorhabditis elegans - genetics; Caenorhabditis elegans - growth & development; Caenorhabditis elegans - metabolism; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Casein Kinase Idelta - genetics; Casein Kinase Idelta - metabolism; Cell differentiation, maturation, development, hematopoiesis; Cell physiology; Circadian Rhythm - genetics; Drosophila; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Developmental; Genes, Helminth; Isoenzymes - genetics; Isoenzymes - metabolism; MicroRNAs; Models, Biological; Molecular and cellular biology; Molecular Sequence Data; Mutation; Phenotype; Phylogeny; RNA Interference
• ISSN: 1534-5807; 1878-1551
• DOI: 10.1016/j.devcel.2004.12.006

In Caenorhabditis elegans, heterochronic genes constitute a developmental timer that specifies temporal cell fate selection. The heterochronic gene lin-42 is the C. elegans homolog of Drosophila and mammalian period, key regulators of circadian rhythms, which specify changes in behavior and physiology over a 24 hr day/night cycle. We show a role for two other circadian gene homologs, tim-1 and kin-20, in the developmental timer. Along with lin-42, tim-1 and kin-20, the C. elegans homologs of the Drosophila circadian clock genes timeless and doubletime, respectively, are required to maintain late-larval identity and prevent premature expression of adult cell fates. The molecular parallels between circadian and developmental timing pathways suggest the existence of a conserved molecular mechanism that may be used for different types of biological timing.