Tissue and lineage-specific variation in inactive X chromosome expression of the murine Smcx gene.
To understand how gene expression patterns are established on the inactive X chromosome during development, we have studied the murine gene Smcx, which is expressed from both the active and inactive mouse X chromosomes. In all tissues assayed, Smcx only partially escapes X inactivation, with expression levels from the inactive X allele approximately 30-65% that of the active X allele. Additionally, inactive X expression levels differed between extraembryonic and embryonic tissues and among different tissues from newborn and adult mice. Imprinted extraembryonic tissue had the lowest levels of inactive X Smcx expression, whereas the highest levels were in heart. These data suggest that the chromosomal basis of X inactivation differs among tissues, perhaps reflecting differences in the timing or regulation of inactivation in these cell lineages.
Carrel
L
L
Department of Genetics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
Hunt
P A
PA
Willard
H F
HF
D000818:Animals; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D056466:Histone Demethylases; D051379:Mice; D010089:Oxidoreductases, N-Demethylating; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000235:genetics*; D014960:X Chromosome / Q000235:genetics*
D011506:Proteins; D056466:Histone Demethylases; C490173:Kdm5c protein, mouse; D010089:Oxidoreductases, N-Demethylating