AJP - Gastrointestinal and Liver Physiology, Vol 268, Issue 6 1074-G1078, Copyright © 1995 by American Physiological Society
Facilitated DNA transfer to rat submandibular gland in vivo and GRP-Ca gene regulation
B. C. O'Connell, K. G. Ten Hagen, K. W. Lazowski, L. A. Tabak and B. J. Baum
Clinical Investigations and Patient Care Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, Maryland 20892-1190, USA.
The internalization of DNA can be facilitated by adenovirus infection.
Using the replication-deficient adenovirus, Ad-dl312, and a plasmid-based
firefly luciferase gene as a reporter, we have optimized the uptake and
expression of DNA in rat submandibular glands in vivo. Luciferase
expression is transient and peaked at approximately 18 h after infection.
Luciferase activity increased with plasmid concentration and was greatest
at 10(9) to 10(10) plaque-forming units of Ad-dl312 per gland. We next
examined the expression in vivo of plasmids containing deletions of the
glutamine/glutamic acid-rich protein (GRP-Ca isoform) gene upstream region
linked to a chloramphenicol acetyltransferase (CAT) reporter. Constructs
with 9.4, 6.3, and 2.7 kb and 17 base pairs of upstream sequence gave
relative CAT activities of 100, 30, 7.6, and 38.5, respectively. With the
9.4-kb GRP-Ca construct, CAT was preferentially expressed in acinar cells,
which is characteristic of GRP. This gene transfer approach should prove
useful in the further study of gene expression in salivary glands and other
organs.
