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Two classes of dosage compensation complex binding elements along Caenorhabditis elegans X chromosomes.

ABSTRACT: Dosage compensation equalizes X-linked gene products between the sexes. In Caenorhabditis elegans, the dosage compensation complex (DCC) binds both X chromosomes in XX animals and halves the transcription from each. The DCC is recruited to the X chromosomes by a number of loci, rex sites, and is thought to spread from these sites by an unknown mechanism to cover the rest of the chromosome. Here we describe a novel class of DCC-binding elements that we propose serve as "way stations" for DCC binding and spreading. Both rex sites and way stations comprise strong foci of DCC binding on the native X chromosome. However, rex sites maintain their ability to bind large amounts of DCC even on X duplications detached from the native X, while way stations do not. These results suggest that two distinct classes of DCC-binding elements facilitate recruitment and spreading of the DCC along the X chromosome.

SUBMITTER: Blauwkamp TA

PROVIDER: S-EPMC2663307 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Two classes of dosage compensation complex binding elements along Caenorhabditis elegans X chromosomes.

Blauwkamp Timothy A TA Csankovszki Gyorgyi G

Molecular and cellular biology 20090202 8

Dosage compensation equalizes X-linked gene products between the sexes. In Caenorhabditis elegans, the dosage compensation complex (DCC) binds both X chromosomes in XX animals and halves the transcription from each. The DCC is recruited to the X chromosomes by a number of loci, rex sites, and is thought to spread from these sites by an unknown mechanism to cover the rest of the chromosome. Here we describe a novel class of DCC-binding elements that we propose serve as "way stations" for DCC bind ...[more]

PMID: 19188444

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