DEVELOPMENTAL EXPRESSION OF H3.3A VARIANT HISTONE MESSENGER-RNA IN MOUSE

Cloning and characterization of H3.3A variant histone expression has r ecently been reported to be associated with meiotic development in mou se testis and ovary. Using Northern analysis and in situ hybridization , the pattern of H3.3A expression was studied during the development o f different tissues. In addition to the differential expression detect ed in male and female meiosis, H3.3A was found to be highly expressed in preantral follicles of adult ovaries and in the basal regions of se miniferous epithelium corresponding to spermatogonia. Different patter ns of expression were observed in somatic tissues, which also differed with respect to the developmental stage of the tissue. The lowest exp ression was detected in adult skeletal muscle. High expressions were f ound in foetal liver and spinal cord. These different expressions migh t reflect a possible function of H3.3A in cell differentiation as dete cted in MEL cells.