caa a22 4500 397574932 CHVBK 20180308164852.0 cr unu---uuuuu 161202e199611 xx s 000 0 eng 10.1093/hmg/5.11.1749 doi (NATIONALLICENCE)oxford-10.1093/hmg/5.11.1749 Alternate Promoters and Alternate Splicing of Human Tenascin-X, a Gene with 5′ and 3′ Ends Buried in Other Genes [Elektronische Daten] [Mart Speek, Floyd Barry, Walter L. Miller] Tenascin-X (TN-X) is an extracellular matrix protein encoded by a large gene that overlaps the steroid 21-hydroxylase (P450c21) gene in the HLA locus on chromosome 6p21.3. This may be the most complex locus in the human genome identified to date, containing 13 overlapping transcription units in 160 kb of DNA. Previous studies determined the sequence of 39 TN-X exons, encoding a 12 kb open reading frame, but the promoter(s) of the gene had not been located. We identify the principal TN-X promoter and a previously unknown 5′ untranslated exon that lies more than 10 kb upstream from the previously known exons. This promoter, which is substantially different from the promoter for TN-C, initiates transcription in human fetal adrenal and muscle, but expression in human NCI-H295 adrenocortical carcinoma cells is initiated by two other promoters lying further upstream. One of these is the same as the promoter for a recently identified Creb-related protein (Creb-rp), but transcripts initiated from this promoter in human adrenal NCI-H295 tumor cells are spliced differently from Creb-rp, and are largely retained in the nuclei of these cells. By analogy with the other two members of the tenascin family, TN-C and TN-R, it has been predicted that TN-X should undergo alternate splicing in its fibronectin-like domains. RACE cloning and RNase protection experiments reveal no such alternate splicing. The TN-X gene appears to be unique in having both its 5′ and 3′ ends buried in other genes. © 1996 Oxford University Press Speek Mart Department of Pediatrics and the Metabolic Research Unit, University of California, San Francisco, CA 94143-0978, USA aut Barry Floyd Department of Pediatrics and the Metabolic Research Unit, University of California, San Francisco, CA 94143-0978, USA aut Miller Walter L. Department of Pediatrics and the Metabolic Research Unit, University of California, San Francisco, CA 94143-0978, USA aut Human Molecular Genetics Oxford University Press 5/11(1996-11), 1749-1758 0964-6906 5:11<1749 1996 5 hmg https://doi.org/10.1093/hmg/5.11.1749 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/hmg/5.11.1749 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Speek Mart Department of Pediatrics and the Metabolic Research Unit, University of California, San Francisco, CA 94143-0978, USA aut NATIONALLICENCE 700 1- Barry Floyd Department of Pediatrics and the Metabolic Research Unit, University of California, San Francisco, CA 94143-0978, USA aut NATIONALLICENCE 700 1- Miller Walter L. Department of Pediatrics and the Metabolic Research Unit, University of California, San Francisco, CA 94143-0978, USA aut NATIONALLICENCE 773 0- Human Molecular Genetics Oxford University Press 5/11(1996-11), 1749-1758 0964-6906 5:11<1749 1996 5 hmg Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford