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Identification of chromosome sequence motifs that mediate meiotic pairing and synapsis in C. elegans.

ABSTRACT: Caenorhabditis elegans chromosomes contain specialized regions called pairing centres, which mediate homologous pairing and synapsis during meiosis. Four related proteins, ZIM-1, 2, 3 and HIM-8, associate with these sites and are required for their essential functions. Here we show that short sequence elements enriched in the corresponding chromosome regions selectively recruit these proteins in vivo. In vitro analysis using SELEX indicates that the binding specificity of each protein arises from a combination of two zinc fingers and an adjacent domain. Insertion of a cluster of recruiting motifs into a chromosome lacking its endogenous pairing centre is sufficient to restore homologous pairing, synapsis, crossover recombination and segregation. These findings help to illuminate how chromosome sites mediate essential aspects of meiotic chromosome dynamics.

SUBMITTER: Phillips CM

PROVIDER: S-EPMC4001799 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Identification of chromosome sequence motifs that mediate meiotic pairing and synapsis in C. elegans.

Phillips Carolyn M CM Meng Xiangdong X Zhang Lei L Chretien Jacqueline H JH Urnov Fyodor D FD Dernburg Abby F AF

Nature cell biology 20090720 8

Caenorhabditis elegans chromosomes contain specialized regions called pairing centres, which mediate homologous pairing and synapsis during meiosis. Four related proteins, ZIM-1, 2, 3 and HIM-8, associate with these sites and are required for their essential functions. Here we show that short sequence elements enriched in the corresponding chromosome regions selectively recruit these proteins in vivo. In vitro analysis using SELEX indicates that the binding specificity of each protein arises fro ...[more]

PMID: 19620970

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