Abundance of female-biased and paucity of male-biased somatically expressed genes on the mouse X-chromosome

BMC Genomics

Research Article

Robert W Williams¹  Gaurav K Pandey²  Chandrasekhar Kanduri³  Elena Jazin⁴  Martin M Johansson⁴  Katarzyna J Radomska⁴  Björn Reinius⁵  Rickard Sandberg⁶  Edward H Morrow⁷ 

[1] Department of Anatomy and Neurobiology, University of Tennessee, Knoxville, USA;Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden;Department of Medical and Clinical Genetics, Department of Biomedicine, The Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden;Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden;Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden;Ludwig Institute for Cancer Research, Stockholm, Sweden;Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden;Ludwig Institute for Cancer Research, Stockholm, Sweden;Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden;School of Life Sciences, University of Sussex, Brighton, United Kingdom;

关键词: X-chromosome;    Sex chromosome;    Somatic;    Gene expression;    Sexual antagonism;    Sexual selection;    Gender;    Sex-bias;    Female-bias;    Male-bias;    Sexual dimorphism;    Dosage compensation;    X-inactivation;    Escape;    Feminisation;    Masculinisation;    De-masculinisation;    Microarray;    Non-coding RNA;    lncRNA;    Tmem29;    Kdm5c;    Xist;   

DOI  :  10.1186/1471-2164-13-607

 received in 2011-12-23, accepted in 2012-10-08,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundEmpirical evaluations of sexually dimorphic expression of genes on the mammalian X-chromosome are needed to understand the evolutionary forces and the gene-regulatory mechanisms controlling this chromosome. We performed a large-scale sex-bias expression analysis of genes on the X-chromosome in six different somatic tissues from mouse.ResultsOur results show that the mouse X-chromosome is enriched with female-biased genes and depleted of male-biased genes. This suggests that feminisation as well as de-masculinisation of the X-chromosome has occurred in terms of gene expression in non-reproductive tissues. Several mechanisms may be responsible for the control of female-biased expression on chromosome X, and escape from X-inactivation is a main candidate. We confirmed escape in case of Tmem29 using RNA-FISH analysis. In addition, we identified novel female-biased non-coding transcripts located in the same female-biased cluster as the well-known coding X-inactivation escapee Kdm5c, likely transcribed from the transition-region between active and silenced domains. We also found that previously known escapees only partially explained the overrepresentation of female-biased X-genes, particularly for tissue-specific female-biased genes. Therefore, the gene set we have identified contains tissue-specific escapees and/or genes controlled by other sexually skewed regulatory mechanisms. Analysis of gene age showed that evolutionarily old X-genes (>100 myr, preceding the radiation of placental mammals) are more frequently female-biased than younger genes.ConclusionAltogether, our results have implications for understanding both gene regulation and gene evolution of mammalian X-chromosomes, and suggest that the final result in terms of the X-gene composition (masculinisation versus feminisation) is a compromise between different evolutionary forces acting on reproductive and somatic tissues.

【 授权许可】

CC BY   
© Reinius et al.; licensee BioMed Central Ltd. 2012