The broad goal of this work is to understand the genetic and molecular mechanisms of the control of cell division and differentiation during animal development. We will chiefly use C. elegans as a model system. Genetic and molecular analysis of C. elegans heterochronic genes will be performed to determine how this regulatory pathway controls the temporally coordinated expression of diverse developmental events in C. elegans larvae. Genetic and biochemical experiments will be performed to explore the molecular mechanisms of how lin-14 and lin-28, genes that play central roles in the control of diverse larval cell lineages, are regulated post-transcriptionally by the microRNA products of the lin-4 and let-7 family genes. There are at least 100 distinct microRNA genes in C. elegans, besides lin-4 and let-7, and the functions of these are largely unknown. We will use molecular and computational approaches to identify additional microRNA genes, and their regulatory targets, and we will employ genetic methods to determine the biological functions of all the C. elegans microRNA genes. C. elegans is an excellent system for the genetic analysis of microRNA function, and since many of the C. elegans microRNAs are conserved in mammals, understanding their roles in C. elegans should inform about the human health significance of microRNA-based regulatory circuits.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
2R01GM034028-21
Application #
6876873
Study Section
Special Emphasis Panel (ZRG1-DEV-1 (01))
Program Officer
Haynes, Susan R
Project Start
1984-07-01
Project End
2008-11-30
Budget Start
2004-12-02
Budget End
2005-11-30
Support Year
21
Fiscal Year
2005
Total Cost
$584,352
Indirect Cost
Name
Dartmouth College
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
041027822
City
Hanover
State
NH
Country
United States
Zip Code
03755
Ambros, Victor; Ruvkun, Gary (2018) Recent Molecular Genetic Explorations of Caenorhabditis elegans MicroRNAs. Genetics 209:651-673
McJunkin, Katherine; Ambros, Victor (2017) A microRNA family exerts maternal control on sex determination in C. elegans. Genes Dev 31:422-437
Ren, Zhiji; Veksler-Lublinsky, Isana; Morrissey, David et al. (2016) Staufen Negatively Modulates MicroRNA Activity in Caenorhabditis elegans. G3 (Bethesda) 6:1227-37
Burke, Samantha L; Hammell, Molly; Ambros, Victor (2015) Robust Distal Tip Cell Pathfinding in the Face of Temperature Stress Is Ensured by Two Conserved microRNAS in Caenorhabditis elegans. Genetics 200:1201-18
Ren, Zhiji; Ambros, Victor R (2015) Caenorhabditis elegans microRNAs of the let-7 family act in innate immune response circuits and confer robust developmental timing against pathogen stress. Proc Natl Acad Sci U S A 112:E2366-75
Sterling, Catherine H; Veksler-Lublinsky, Isana; Ambros, Victor (2015) An efficient and sensitive method for preparing cDNA libraries from scarce biological samples. Nucleic Acids Res 43:e1
Zinovyeva, Anna Y; Veksler-Lublinsky, Isana; Vashisht, Ajay A et al. (2015) Caenorhabditis elegans ALG-1 antimorphic mutations uncover functions for Argonaute in microRNA guide strand selection and passenger strand disposal. Proc Natl Acad Sci U S A 112:E5271-80
Harandi, Omid F; Ambros, Victor R (2015) Control of stem cell self-renewal and differentiation by the heterochronic genes and the cellular asymmetry machinery in Caenorhabditis elegans. Proc Natl Acad Sci U S A 112:E287-96
Nelson, Charles; Ambros, Victor; Baehrecke, Eric H (2014) miR-14 regulates autophagy during developmental cell death by targeting ip3-kinase 2. Mol Cell 56:376-88
Zinovyeva, Anna Y; Bouasker, Samir; Simard, Martin J et al. (2014) Mutations in conserved residues of the C. elegans microRNA Argonaute ALG-1 identify separable functions in ALG-1 miRISC loading and target repression. PLoS Genet 10:e1004286

Showing the most recent 10 out of 52 publications