J Biol Chem, Vol. 273, Issue 12, 6900-6908, March 20, 1998
The Upstream Regulatory Regions of the Hepatocyte Growth Factor
Gene Promoter Are Essential for Its Expression in Transgenic Mice
Aaron W.
Bell,
Jie-Gen
Jiang,
Qiuyan
Chen,
Youhua
Liu, and
Reza
Zarnegar
From the Department of Pathology, Division of Cellular and
Molecular Pathology, University of Pittsburgh, School of Medicine,
Pittsburgh, Pennsylvania 15261
To understand the molecular mechanisms of
hepatocyte growth factor (HGF) gene transcription in vivo,
we report the generation and characterization of transgenic mice
harboring various lengths of the mouse HGF promoter linked to the
chloramphenicol acetyltransferase reporter gene. Analysis of different
tissues of the transgenic mouse lines having the 2.7-kilobase (kb)
promoter construct revealed a pattern of reporter gene expression in
embryonic and adult tissues that paralleled that of endogenous HGF gene
expression. A similar expression pattern was observed in the 0.7-kb
transgenic lines. However, in contrast to in vitro data, no
promoter activity was detected in four independent transgenic lines
harboring the 0.1-kb construct. Akin to the activity of the endogenous
HGF gene, which is induced in the liver, lung, and spleen in response
to 70% partial hepatectomy, the reporter gene driven by the 2.7-kb
promoter construct was strongly induced, whereas that driven by the
0.7-kb promoter construct was modestly induced in these organs after
partial hepatectomy. Together, these data suggest that the region
between
0.1 and
0.7 kb of the HGF gene promoter is essential to
drive its expression in vivo and that additional upstream
sequences located between
0.7 and
2.7 kb are also necessary for its
maximum inducibility in response to cues that stimulate tissue growth
and regeneration.
Copyright © 1998 by The American Society for Biochemistry and Molecular Biology, Inc.