HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 16/1/119    most recent 00167.2002v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (5) Citing Articles via Google Scholar Google Scholar Articles by Squire, T. L. Articles by Andrews, M. T. Search for Related Content PubMed PubMed Citation Articles by Squire, T. L. Articles by Andrews, M. T.

Pancreatic triacylglycerol lipase in a hibernating mammal. I. Novel genomic organization

¹ Department of Genetics, North Carolina State University, Raleigh, North Carolina 27695-7614
² Department of Biology, University of Minnesota Duluth, Duluth, Minnesota 55812

Pancreatic triacylglycerol lipase (PTL) is expressed in novel locations during hibernation in the thirteen-lined ground squirrel (Spermophilus tridecemlineatus). PTL cDNAs isolated from two of these locations, heart and white adipose tissue (WAT), contain divergent 5'-untranslated regions (5'-UTRs) suggesting alternative promoter usage or the possibility of multiple PTL genes in the ground squirrel genome. In addition, cDNAs isolated from WAT contain tracts of retroviral sequence in their 5'-UTRs. Our examination of PTL genomic clones isolated from a thirteen-lined ground squirrel genomic DNA library, coupled with genomic Southern blot analysis, enabled us to conclude that PTL mRNAs expressed in heart and WAT are the products of the same single-copy gene. The 5' portion of this gene spans 9.2 kb, is composed of 6 exons, and contains a full-length endogenous retroviral genome with conserved long terminal repeats (LTRs). Alignment of the ground squirrel PTL gene with the mouse, rat, and human PTL genes indicates that this retrovirus inserted into the ground squirrel genome 200 bases upstream of the original PTL transcriptional start site. The insertion is a relatively recent event based on largely intact open-reading frames containing minimal frame-shift and nonsense mutations. The high-percentage identity (99.2%) shared between the 5'- and 3'-LTRs of this endogenous retrovirus suggests that the insertion occurred as recently as 300,000 years ago.

endogenous retrovirus; retroviral insertion; hibernation; promoter; genome

This article has been cited by other articles:

				K. M. Brauch, N. D. Dhruv, E. A. Hanse, and M. T. Andrews Digital transcriptome analysis indicates adaptive mechanisms in the heart of a hibernating mammal Physiol Genomics, October 17, 2005; 23(2): 227 - 234. [Abstract] [Full Text] [PDF]

				T. L. Squire, M. E. Lowe, V. W. Bauer, and M. T. Andrews Pancreatic triacylglycerol lipase in a hibernating mammal. II. Cold-adapted function and differential expression Physiol Genomics, December 16, 2003; 16(1): 131 - 140. [Abstract] [Full Text] [PDF]