Transcriptional changes in response to X chromosome dosage in the mouse: implications for X inactivation and the molecular basis of Turner Syndrome

• Tipo: Artigo em Revista Científica Internacional
• Data: 2010

Autores

Alexandra M Lopes (Autor) FCUP; Paul S Burgoyne (Autor) Outra; Andrew Ojarikre (Autor) Outra; Julien Bauer (Autor) Outra; Carole A Sargent (Autor) Outra; Antonio Amorim (Autor) FCUP; Nabeel A Affara (Autor) Outra

Revista

Título: BMC Genomics

Vol. 11

Página Final: 82

ISSN: 1471-2164

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 44 Citações

Scopus - 47 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Ciências biológicas

Outras Informações

ID Authenticus: P-003-98H

DOI: 10.1186/1471-2164-11-82

Abstract (EN): Background: X monosomic mice (39, XO) have a remarkably mild phenotype when compared to women with Turner syndrome (45, XO). The generally accepted hypothesis to explain this discrepancy is that the number of genes on the mouse X chromosome which escape X inactivation, and thus are expressed at higher levels in females, is very small. However this hypothesis has never been tested and only a small number of genes have been assayed for their X-inactivation status in the mouse. We performed a global expression analysis in four somatic tissues (brain, liver, kidney and muscle) of adult 40, XX and 39, XO mice using the Illumina Mouse WG-6 v1_1 Expression BeadChip and an extensive validation by quantitative real time PCR, in order to identify which genes are expressed from both X chromosomes. Results: We identified several genes on the X chromosome which are overexpressed in XX females, including those previously reported as escaping X inactivation, as well as new candidates. However, the results obtained by microarray and qPCR were not fully concordant, illustrating the difficulty in ascertaining modest fold changes, such as those expected for genes escaping X inactivation. Remarkably, considerable variation was observed between tissues, suggesting that inactivation patterns may be tissue-dependent. Our analysis also exposed several autosomal genes involved in mitochondrial metabolism and in protein translation which are differentially expressed between XX and XO mice, revealing secondary transcriptional changes to the alteration in X chromosome dosage. Conclusions: Our results support the prediction that the mouse inactive X chromosome is largely silent, while providing a list of the genes potentially escaping X inactivation in rodents. Although the lower expression of X-linked genes in XO mice may not be relevant in the particular tissues/systems which are affected in human X chromosome monosomy, genes deregulated in XO mice are good candidates for further study in an involvement in Turner Syndrome phenotype.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 12