Telokin expression is mediated by a smooth muscle cell-specific
promoter.
Herring, B. Paul, and Aiping F. Smith.
Department of Physiology and Biophysics, Indiana University School
of Medicine, Indianapolis, IN 46202-5120
APStracts 2:0420C, 1995.
The carboxyl-terminus of the smooth muscle myosin light chain kinase
(smMLCK) is expressed as an independent protein, telokin. Western and
Northern blotting analysis demonstrated that telokin protein and mRNA
are expressed at high levels only in adult and embryonic smooth
muscle tissues and cells. In vitro transfection assays, in A10 smooth
muscle cells, identified a functional promoter located in an intron
in the 3' region of the smMLCK gene that directs the smooth muscle
cell-specific transcription of telokin. To test the cell specificity
of the telokin promoter in vivo, transgenic mice were generated in
which the telokin promoter was used to drive expression of SV40 Large
T-antigen. Expression of T-antigen in the transgenic mice paralleled
that of the endogenous telokin gene. High levels of T-antigen
expression were observed in smooth muscle tissues of the digestive,
urinary and reproductive tract, and lower levels of expression in
airway and vascular smooth muscle. Expression was restricted to
smooth muscle cells, with no expression detected in any other cell
type.
Received 26 September 1995; accepted in final form 17 November
1995.
APS Manuscript Number C589-5.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 8 December 95