Sexual Dimorphism in Mammalian Autosomal Gene Regulation Is Determined Not Only by Sry but by Sex Chromosome Complement As Well

SummaryDifferences between males and females are normally attributed to developmental and hormonal differences between the sexes. Here, we demonstrate differences between males and females in gene silencing using a heterochromatin-sensitive reporter gene. Using “sex-reversal” mouse models with varying sex chromosome complements, we found that this differential gene silencing was determined by X chromosome complement, rather than sex. Genome-wide transcription profiling showed that the expression of hundreds of autosomal genes was also sensitive to sex chromosome complement. These genome-wide analyses also uncovered a role for Sry in modulating autosomal gene expression in a sex chromosome complement-specific manner. The identification of this additional layer in the establishment of sexual dimorphisms has implications for understanding sexual dimorphisms in physiology and disease.PaperClip To listen to this audio, enable JavaScript on your browser. However, you can download and play the audio by clicking on the icon belowHelp with MP3 filesOptionsDownload audio (2130 K)

► Heterochromatin-mediated gene silencing varies between males and females ► X chromosome dosage regulates heterochromatin-mediated gene silencing ► Sex chromosome complement regulates a subset of autosomal genes ► Sry affects sexually dimorphic gene expression in a sex chromosome-dependent manner