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Cytoplasmic partitioning of P granule components is not required to specify the germline in C. elegans.

ABSTRACT: Asymmetric segregation of P granules during the first four divisions of the Caenorhabditis elegans embryo is a classic example of cytoplasmic partitioning of germline determinants. It is thought that asymmetric partitioning of P granule components during mitosis is essential to distinguish germline from soma. We have identified a mutant (pptr-1) in which P granules become unstable during mitosis and P granule proteins and RNAs are distributed equally to somatic and germline blastomeres. Despite symmetric partitioning of P granule components, pptr-1 mutants segregate a germline that uniquely expresses P granules during postembryonic development. pptr-1 mutants are fertile, except at high temperatures. Hence, asymmetric partitioning of maternal P granules is not essential to specify germ cell fate. Instead, it may serve to protect the nascent germline from stress.

SUBMITTER: Gallo CM

PROVIDER: S-EPMC3072820 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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Cytoplasmic partitioning of P granule components is not required to specify the germline in C. elegans.

Gallo Christopher M CM Wang Jennifer T JT Motegi Fumio F Seydoux Geraldine G

Science (New York, N.Y.) 20101202 6011

Asymmetric segregation of P granules during the first four divisions of the Caenorhabditis elegans embryo is a classic example of cytoplasmic partitioning of germline determinants. It is thought that asymmetric partitioning of P granule components during mitosis is essential to distinguish germline from soma. We have identified a mutant (pptr-1) in which P granules become unstable during mitosis and P granule proteins and RNAs are distributed equally to somatic and germline blastomeres. Despite ...[more]

PMID: 21127218

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