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X Chromosome and Autosome Dosage Responses in Drosophila melanogaster Heads.

ABSTRACT: X chromosome dosage compensation is required for male viability in Drosophila. Dosage compensation relative to autosomes is two-fold, but this is likely to be due to a combination of homeostatic gene-by-gene regulation and chromosome-wide regulation. We have baseline values for gene-by-gene dosage compensation on autosomes, but not for the X chromosome. Given the evolutionary history of sex chromosomes, these baseline values could differ. We used a series of deficiencies on the X and autosomes, along with mutations in the sex-determination gene transformer-2, to carefully measure the sex-independent X-chromosome response to gene dosage in adult heads by RNA sequencing. We observed modest and indistinguishable dosage compensation for both X chromosome and autosome genes, suggesting that the X chromosome is neither inherently more robust nor sensitive to dosage change.

SUBMITTER: Chen ZX

PROVIDER: S-EPMC4478536 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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X Chromosome and Autosome Dosage Responses in Drosophila melanogaster Heads.

Chen Zhen-Xia ZX Oliver Brian B

G3 (Bethesda, Md.) 20150407 6

X chromosome dosage compensation is required for male viability in Drosophila. Dosage compensation relative to autosomes is two-fold, but this is likely to be due to a combination of homeostatic gene-by-gene regulation and chromosome-wide regulation. We have baseline values for gene-by-gene dosage compensation on autosomes, but not for the X chromosome. Given the evolutionary history of sex chromosomes, these baseline values could differ. We used a series of deficiencies on the X and autosomes, ...[more]

PMID: 25850426

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