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X-chromosome targeting and dosage compensation are mediated by distinct domains in MSL-3.

ABSTRACT: In Drosophila, dosage compensation of X-linked genes is achieved by transcriptional upregulation of the male X chromosome. Genetic and biochemical studies have demonstrated that male-specific lethal (MSL) proteins together with roX RNAs regulate this process. Here, we show that MSL-3 is essential for cell viability and that three domains in the protein have distinct roles in dosage compensation. The chromo-barrel domain (CBD) is not necessary for MSL targeting to the male X chromosome but is important for male viability and equalization of X-linked gene transcription. The polar region cooperates with the CBD in MSL-3 function, whereas the MRG domain is responsible for targeting the protein to the X chromosome. Our results demonstrate that MSL-3 localization to the male X chromosome and transcriptional upregulation of X-linked genes are two separable functions of the MSL-3 protein.

SUBMITTER: Buscaino A

PROVIDER: S-EPMC1479548 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature

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X-chromosome targeting and dosage compensation are mediated by distinct domains in MSL-3.

Buscaino Alessia A Legube Gaëlle G Akhtar Asifa A

EMBO reports 20060310 5

In Drosophila, dosage compensation of X-linked genes is achieved by transcriptional upregulation of the male X chromosome. Genetic and biochemical studies have demonstrated that male-specific lethal (MSL) proteins together with roX RNAs regulate this process. Here, we show that MSL-3 is essential for cell viability and that three domains in the protein have distinct roles in dosage compensation. The chromo-barrel domain (CBD) is not necessary for MSL targeting to the male X chromosome but is imp ...[more]

PMID: 16547465

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