The testis-specific histone H1t gene is expressed only in pachytene primary spermatocytes during spermatogenesis. There is a correlation between the specific binding of testis nuclear proteins to a rat histone H1t promoter sequence, designated the H1t/TE element, and the onset of transcription in primary spermatocytes. Our laboratory has shown that mice bearing the rat gene with a deletion of the TE promoter element and replacement with a heterologous stuffer DNA fragment fail to express the rat H1t transgene in any tissue. In this study we report that five CpGs located within the H1t proximal promoter, including two CpGs located within the essential TE promoter element, contain unmethylated cytosines in vivo in genomic DNA derived from primary spermatocytes where the H1t gene is expressed. All seven CpGs are hypermethylated in vivo in genomic DNA derived from liver cells where gene expression is repressed. Further, in vitro methylation of an H1t promoter-driven reporter plasmid markedly reduced expression in a transient transfection assay system. These results suggest that cytosine methylation may contribute to the transcriptional silencing of the testis-specific histone H1t gene in nonexpressing tissues such as liver.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.