Caenorhabditis elegans compensates for the difference in X chromosome dosage between the sexes by regulating transcript levels.
The primary sex-determining signal in the nematode C. elegans is the ratio of X chromosomes to sets of autosomes (X/A ratio). As a consequence, males (XO; ratio 0.5) and hermaphrodites (XX; ratio 1.0) possess different doses of X-linked genes. Here we demonstrate that C. elegans compensates for this disparity in gene dose by equalizing the levels of X-specific mRNA transcripts in the two sexes. Moreover, we show that mutations in three autosomal genes disrupt the process of dosage compensation. Reduction in the activity of either dpy-21, dpy-27, or dpy-28 results in the overexpression of X-specific genes, 2- to 3-fold above wild-type levels.
D000818:Animals; D002107:Caenorhabditis / Q000235:genetics*; D012734:Disorders of Sex Development; D004303:Dosage Compensation, Genetic; D005260:Female; D008040:Genetic Linkage; D008297:Male; D009154:Mutation; D009218:Myosins / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D014960:X Chromosome
D012333:RNA, Messenger; D009218:Myosins