Nucleic Acids Research, Vol 26, Issue 17 4025-4033, Copyright © 1998 by Oxford University Press
MG Lee
An increase in the transcriptional efficiency at elevated temperatures is a
characteristic of transcription of heat shock protein (hsp) coding genes in
most eukaryotes analyzed to date. The regulatory mechanism for hsp 70 genes
expression in Trypanosoma brucei does not follow the conventional
transcriptional induction mechanism. The hsp 70 locus of T.brucei appears
in a permanently activated state, and transcriptional induction of hsp 70
genes by heat shock does not occur in this organism. Therefore, the
differential expression of the hsp 70 genes in trypanosomes is, to a large
extent, post-transcriptionally controlled. Mechanisms of
post-transcriptional control of the hsp 70 gene expression were
investigated. Procyclic trypanosomes were normally maintained at
approximately 25 degreesC. Incubation of procyclic trypanosomes at 41
degreesC drastically reduced the steady state mRNA levels of many protein
coding genes. In contrast, the expression of the hsp 70 genes is either
maintained at a high level or is up-regulated. The hsp 70 intergenic region
promoter together with its 3' splice acceptor sites and the 5' untranslated
region (UTR) are not sufficient to maintain or up-regulate the mRNA level
of a reporter gene upon heat shock. However, addition of the 3' UTR of hsp
70 genes to a reporter gene, driven by different promoters, maintained a
high level expression of the mRNA during heat shock. These results
suggested that the 3' UTR of the hsp 70 genes is primarily responsible for
the maintenance of mRNA level during heat shock, while mRNA containing the
3' UTR from many other genes may be rapidly degraded by heat shock induced
processes.
ARTICLES
The 3' untranslated region of the hsp 70 genes maintains the level of steady state mRNA in Trypanosoma brucei upon heat shock
Department of Pathology, New York University Medical Center, 550 First Avenue, New York, NY 10016, USA. lee02@mcrcr6.med.nyu.edu
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  S. Kramer, R. Queiroz, L. Ellis, H. Webb, J. D. Hoheisel, C. Clayton, and M. Carrington Heat shock causes a decrease in polysomes and the appearance of stress granules in trypanosomes independently of eIF2{alpha} phosphorylation at Thr169 J. Cell Sci., September 15, 2008; 121(18): 3002 - 3014. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Zilka, S. Garlapati, E. Dahan, V. Yaolsky, and M. Shapira Developmental Regulation of Heat Shock Protein 83 in Leishmania. 3' PROCESSING AND mRNA STABILITY CONTROL TRANSCRIPT ABUNDANCE, AND TRANSLATION IS DIRECTED BY A DETERMINANT IN THE 3'-UNTRANSLATED REGION J. Biol. Chem., December 14, 2001; 276(51): 47922 - 47929. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Di Noia, I. D'Orso, D. O. Sanchez, and A. C. C. Frasch AU-rich Elements in the 3'-Untranslated Region of a New Mucin-type Gene Family of Trypanosoma cruzi Confers mRNA Instability and Modulates Translation Efficiency J. Biol. Chem., March 31, 2000; 275(14): 10218 - 10227. [Abstract] [Full Text] [PDF]
|
|