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PUF-8, a Pumilio homolog, inhibits the proliferative fate in the Caenorhabditis elegans germline.

ABSTRACT: Stem cell populations are maintained by keeping a balance between self-renewal (proliferation) and differentiation of dividing stem cells. Within the Caenorhabditis elegans germline, the key regulator maintaining this balance is the canonical Notch signaling pathway, with GLP-1/Notch activity promoting the proliferative fate. We identified the Pumilio homolog, PUF-8, as an inhibitor of the proliferative fate of stem cells in the C. elegans germline. puf-8(0) strongly enhances overproliferation of glp-1(gf) mutants and partially suppresses underproliferation of a weak glp-1(lf) mutant. The germline tumor that is formed in a puf-8(0); glp-1(gf) double mutant is due to a failure of germ cells to enter meiotic prophase. puf-8 likely inhibits the proliferative fate through negatively regulating GLP-1/Notch signaling or by functioning parallel to it.

SUBMITTER: Racher H

PROVIDER: S-EPMC3464112 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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PUF-8, a Pumilio homolog, inhibits the proliferative fate in the Caenorhabditis elegans germline.

Racher Hilary H Hansen Dave D

G3 (Bethesda, Md.) 20121001 10

Stem cell populations are maintained by keeping a balance between self-renewal (proliferation) and differentiation of dividing stem cells. Within the Caenorhabditis elegans germline, the key regulator maintaining this balance is the canonical Notch signaling pathway, with GLP-1/Notch activity promoting the proliferative fate. We identified the Pumilio homolog, PUF-8, as an inhibitor of the proliferative fate of stem cells in the C. elegans germline. puf-8(0) strongly enhances overproliferation o ...[more]

PMID: 23050230

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