| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Abstract
The mammalian epididymis plays a critical role in sperm
maturation, a function dependent upon testicular
androgens. However, the function of the initial segment,
the most proximal part of the epididymis, is also
dependent upon luminal factors of testicular origin.
Efferent duct ligation (EDL), which prevents luminal
testicular fluid from reaching the epididymis, results in
changes in gene expression within this region.
Cystatin-related epididymal specific (cres) gene
and 
-glutamyl transpeptidase (GGT) mRNA IV are
highly expressed in the initial segment and are regulated
by luminal testicular factors. EDL results in decreased
expression of both genes. To evaluate these promoters in
the context of their native physiological state, an in
vivo electroporation procedure was used. Significant
differences were observed in vivo compared to
previous in vitro results. Whereas two C/EBP sites
were necessary for transcriptional activity from a 135 bp
cres promoter in vitro, only the 5' site
displayed functional activity in the in vivo
system. A 135 bp GGT promoter IV construct was sufficient
for reporter gene expression in vitro. However,
in vivo, substantial expression was not observed
until the construct was extended to 530 bp. Three
polyomavirus enhancer activator 3 (PEA3) sites were found
to be necessary for in vivo reporter gene
expression from this construct. A cis-acting
negative regulatory element between -530 and -681 bp was
also identified that was not previously recognized in the
in vitro studies. These studies demonstrate the
utility of in vivo electroporation for elucidating
promoter elements that may not be identified when
traditional in vitro methods are used.
Key words:
Male Reproductive Tract •
Epididymis •
Gene regulation
This article has been cited by other articles:
|
|
 |
|
  W. R. Lagor, R. Heller, E. D. De Groh, and G. C. Ness Functional Analysis of the Hepatic HMG-CoA Reductase Promoter by In Vivo Electroporation Experimental Biology and Medicine, March 1, 2007; 232(3): 353 - 361. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Yang, S. A. Fox, J. L. Kirby, B. V. Troan, and B. T. Hinton Putative Regulation of Expression of Members of the Ets Variant 4 Transcription Factor Family and Their Downstream Targets in the Rat Epididymis Biol Reprod, April 1, 2006; 74(4): 714 - 720. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. V. Zubkova and B. Robaire Editorial Commentary J Androl, September 1, 2005; 26(5): 638 - 640. [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
