|
|
||||||||
Correspondence to:
Wolfgang Patsch
Previous studies have shown that the elongation phase of apoA-I gene transcription is regulated and contributes to hormone-induced changes in the expression of this gene in rat liver. We have now identified, by in vitro transcription studies with HeLa nuclear extracts, two transcriptional arrest sites within exon 3 and intron 3, respectively. Two truncated transcripts of 510 and ~1100 nucleotides in length, termed attenuator 1 RNA and attenuator 2 RNA, respectively, were observed when a rat apoA-I genomic fragment extending from -309 to +1842 relative to the transcription start site was transcribed in vitro in the presence of KCl or Sarkosyl. The attenuation events were promoter-independent as transcription of the apoA-I gene driven by the cytomegalovirus promoter resulted in transcriptional arrest at both sites. Transcription studies using deletion constructs as templates identified nucleotides +976 to +1158 as a region that contained the signal for transcriptional arrest at attenuator site 2. Computational analysis predicted a stem;loop structure in the nascent RNA immediately upstream of the arrest site. Deletion of attenuator 2 signal or deletion of sequences +147 to +216 located far upstream of the actual elongation block site 1 abrogated arrest at site 1. Thus, complex long-range interactions may be involved in the transcriptional arrest at site 1.
These elongation blocks identified in vitro are consistent with earlier in vivo data based on nuclear run-on assays and represent, to our knowledge, the first example describing transcriptional attenuation as a mechanism controlling the expression of a member of the apolipoprotein gene family.Dallinger, G., H. Oberkofler, C. Seelos, and W. Patsch. Transcriptional elongation of the rat apolipoprotein A-I gene: identification and mapping of two arrest sites and their signals. J. Lipid Res. 1999. 40: 1229;1239.
Supplementary key words:
apolipoprotein A-I, transcriptional attenuation, elongation block, in vitro transcription
Copyright © 1999 by Lipid Research, Inc.
Original Article
Transcriptional elongation of the rat apolipoprotein A-I gene: identification and mapping of two arrest sites and their signals
Guenter Dallingera,
Hannes Oberkoflera,
Christian Seelosb, and
Wolfgang Patscha
a Department of Laboratory Medicine, Landeskrankenanstalten Salzburg, Salzburg, Austria
b Institute for Tumorbiologie-Krebsforschung, Wien, Austria
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
P. J. Cejas, L. M. Carlson, D. Kolonias, J. Zhang, I. Lindner, D. D. Billadeau, L. H. Boise, and K. P. Lee Regulation of RelB Expression during the Initiation of Dendritic Cell Differentiation Mol. Cell. Biol., September 1, 2005; 25(17): 7900 - 7916. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Journal of Biological Chemistry |
| Molecular and Cellular Proteomics | ASBMB Today |