Growth-suppressive function of human connexin32 in a conditional immortalized mouse hepatocyte cell line

Citation
T. Kojima et al., Growth-suppressive function of human connexin32 in a conditional immortalized mouse hepatocyte cell line, IN VITRO-AN, 37(9), 2001, pp. 589-598
Citations number
41
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell & Developmental Biology
Journal title
IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY-ANIMAL
ISSN journal
1071-2690 → ACNP
Volume
37
Issue
9
Year of publication
2001
Pages
589 - 598
Database
ISI
SICI code
1071-2690(200110)37:9<589:GFOHCI>2.0.ZU;2-3
Abstract
Mouse hepatocytes immortalized with a temperature-sensitive allele of the S V40 large T-antigen (CHST8 cells) were found to lack the high expression of the gap junction proteins Gx26 and Cx32 that characterizes normal mouse he patocytes. expressing instead Cx43 and Cx45 at minimal levels. In order to examine the growth suppressive function of Cx32 on hepatocytes we transfect ed these CHST8 cells with human Cx32 complementary deoxyribonucleic acid an d measured the growth rates at 33, 37, and 39 degrees C. Expression of huma n Cx32 and its messenger ribonucleic acid in the stable cell lines was conf irmed by immunocytochemistry and by Western and Northern blots analyses. Dy e transfer following lucifer yellow injection into the transfectants was ex tensive; Cx32 channels displayed unitary conductances of about 70 pS and we re moderately voltage sensitive. When cultured at 33 and 39 degrees C, grow th rates of both parental cells and transfectants were of the same level. W hen examined at 37 degrees C. growth rate of the transfectant, which highly expressed Cx32 at the membranes, was significantly decreased compared to t he parental cells. However. no changes in the expression of Cx32 protein in the transfectants were observed between 33 and 37 degrees C. These results suggest that Cx32 expression could inhibit hepatocyte growth in vitro usin g the conditional immortalized cells. Cx32 transfectants using a conditiona l immortalized mouse hepatocyte may be useful for examining the mechanisms of growth and differentiation in hepatocytes by gap junction expression.