Title

Characterization of expression at the human XIST locus in somatic, embryonal carcinoma, and transgenic cell lines

Student Author(s)

Christine Clemson

GSBS Program

MS in Clinical Investigation

UMMS Affiliation

Department of Cell Biology

Date

8-9-2003

Document Type

Article

Medical Subject Headings

Animals; Anti-Bacterial Agents; Carcinoma, Embryonal; Cattle; Dactinomycin; Female; Gene Expression; Humans; Male; Mice; RNA, Untranslated; Transgenes

Disciplines

Cell Biology | Life Sciences | Medicine and Health Sciences

Abstract

X inactivation requires XIST, a functional RNA that is expressed exclusively from, and localizes to, the inactive X in female somatic cells. In mouse, low-level unstable transcription of Xist is observed prior to the time of inactivation, and an antisense transcript, Tsix, is a critical regulator of early Xist expression. To examine the presence and impact of an antisense transcript in humans we have characterized the extent of sense and antisense transcription in human somatic, transgenic, and embryonal carcinoma (EC) cell lines. Downstream antisense expression at the human XIST locus was not detected in somatic cells, but was detected in the EC line N-Tera2D1 and in somatic cells with an ectopic XIST locus. Presence of the antisense did not disrupt the stability or localization of the sense transcript. We have also identified additional sense transcripts in EC and female somatic cells and demonstrate that the 5' flanking JPX/ENOX gene is expressed from both the active and the inactive X chromosome in somatic cell hybrids, delimiting the extent of inactive X-specific transcriptional control in somatic cells. These analyses reveal similarities to and differences from the murine Xist and Tsix transcripts and generate a complex picture of developmentally regulated transcription through the region.

Rights and Permissions

Citation: Genomics. 2003 Sep;82(3):309-22.

Related Resources

Link to article in PubMed