A feedback circuit involving let-7-family miRNAs and DAF-12 integrates environmental signals and developmental timing in Caenorhabditis elegans

Hammell, C. M., Karp, X., Ambros, V. (November 2009) A feedback circuit involving let-7-family miRNAs and DAF-12 integrates environmental signals and developmental timing in Caenorhabditis elegans. Proc Natl Acad Sci U S A, 106 (44). pp. 18668-73. ISSN 1091-6490 (Electronic)0027-8424 (Linking)

[thumbnail of Paper]
Preview
PDF (Paper)
Hammell PNAS 2009.pdf - Published Version

Download (847kB) | Preview

Abstract

Animal development is remarkably robust; cell fates are specified with spatial and temporal precision despite physiological and environmental contingencies. Favorable conditions cause Caenorhabditis elegans to develop rapidly through four larval stages (L1-L4) to the reproductive adult. In unfavorable conditions, L2 larvae can enter the developmentally quiescent, stress-resistant dauer larva stage, enabling them to survive for prolonged periods before completing development. A specific progression of cell division and differentiation events occurs with fidelity during the larval stages, regardless of whether an animal undergoes continuous or dauer-interrupted development. The temporal patterning of developmental events is controlled by the heterochronic genes, whose products include microRNAs (miRNAs) and regulatory proteins. One of these proteins, the DAF-12 nuclear hormone receptor, modulates the transcription of certain let-7-family miRNAs, and also mediates the choice between the continuous vs. dauer-interrupted life history. Here, we report a complex feedback loop between DAF-12 and the let-7-family miRNAs involving both the repression of DAF-12 by let-7-family miRNAs and the ligand-modulated transcriptional activation and repression of the let-7-Fam miRNAs by DAF-12. We propose that this feedback loop functions to ensure robustness of cell fate decisions and to coordinate cell fate with developmental arrest.

Item Type: Paper
Uncontrolled Keywords: Animals Caenorhabditis elegans/ growth & development/ metabolism Caenorhabditis elegans Proteins/genetics/ metabolism Environment Feedback, Physiological Gene Expression Regulation, Developmental Ligands MicroRNAs/ metabolism Models, Biological Mutation/genetics Receptors, Cytoplasmic and Nuclear/ metabolism Time Factors
Subjects: organism description > animal > C elegans
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification
bioinformatics > genomics and proteomics > genetics & nucleic acid processing
bioinformatics > genomics and proteomics
organism description > animal
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > miRNA
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > miRNA
CSHL Authors:
Communities: CSHL labs > Hammell C. lab
Depositing User: Matt Covey
Date: 3 November 2009
Date Deposited: 21 Feb 2013 16:48
Last Modified: 08 Nov 2017 20:45
PMCID: PMC2774035
Related URLs:
URI: https://repository.cshl.edu/id/eprint/27376

Actions (login required)

Administrator's edit/view item Administrator's edit/view item