The Caenorhabditis elegans hunchback-like Gene lin-57/hbl-1 Controls Developmental Time and Is Regulated by MicroRNAs

• Published in: Developmental cell Vol. 4; no. 5; pp. 625 - 637
• Main Authors: Abrahante, Juan E., Daul, Aric L., Li, Ming, Volk, Mandy L., Tennessen, Jason M., Miller, Eric A., Rougvie, Ann E.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.2003
• Subjects: 3' Untranslated Regions - genetics; 3' Untranslated Regions - metabolism; Animals; Base Sequence; Binding Sites; Caenorhabditis elegans - genetics; Caenorhabditis elegans - growth & development; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Cell Differentiation; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Epistasis, Genetic; Female; Gene Expression Regulation, Developmental; Locomotion; MicroRNAs - genetics; MicroRNAs - metabolism; Molecular Sequence Data; Mutation; RNA Interference; Time Factors; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 1534-5807; 1878-1551
• DOI: 10.1016/S1534-5807(03)00127-8

Temporal control of development is an important aspect of pattern formation that awaits complete molecular analysis. We identified lin-57 as a member of the C. elegans heterochronic gene pathway, which ensures that postembryonic developmental events are appropriately timed. Loss of lin-57 function causes the hypodermis to terminally differentiate and acquire adult character prematurely. lin-57 is hbl-1, revealing a role for the worm hunchback homolog in control of developmental time. Significantly, fly hunchback ( hb) temporally specifies cell fates in the nervous system. The hbl-1/lin-57 3′UTR is required for postembryonic downregulation in the hypodermis and nervous system and contains multiple putative binding sites for temporally regulated microRNAs, including let-7. Indeed, we find that hbl-1/lin-57 is regulated by let-7, at least in the nervous system. Examination of the hb 3′UTR reveals potential binding sites for known fly miRNAs. Thus, evolutionary conservation of hunchback genes may include temporal control of cell fate specification and microRNA-mediated regulation.