Role of H1-calponin in pancreatic AR42J cell differentiation into insulin-producing cells.
Basic or h1-calponin is a smooth muscle-specific, actin-binding protein that is involved in the regulation of smooth muscle contractile activity. We found in this study the expression of mRNA and protein for h1-calponin in AR42J-B13 cells, which is a useful model for investigating islet beta-cell differentiation from pancreatic common precursor cells. Following treatment of AR42J cells with activin A and hepatocyte growth factor, the protein levels of h1-calponin decreased in a time-dependent manner during the course of the cell differentiation. When h1-calponin was continuously overexpressed by utilizing recombinant adenovirus-mediated gene transfer, the percentage of cell differentiation in h1-calponin overexpressing cells was markedly suppressed as compared with that in the cells without overexpression (6.7 +/- 2.5 vs. 28.6 +/- 3.2%, P < 0.001, Student's t test). Finally, overexpression of h1-calponin (65.6 +/- 3.4), or that lacking actin-binding domain (55.9 +/- 3.4%), significantly (P < 0.001) suppressed the activin A-stimulated transcriptional activity of activin responsive element (ARE), whereas calponin homology-domain disruption mutant did not (100.6 +/- 1.9%). These results suggest that regulation of h1-calponin is involved in the regulation of differentiation of AR42J cells into insulin-producing cells at least partly through modulating ARE transcriptional activity.
Morioka
Tomoaki
T
Department of Metabolism, Endocrinology, and Molecular Medicine, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585, Japan.
Koyama
Hidenori
H
Yamamura
Hisako
H
Tanaka
Shinji
S
Fukumoto
Shinya
S
Emoto
Masanori
M
Mizuguchi
Hiroyuki
H
Hayakawa
Takao
T
Kojima
Itaru
I
Takahashi
Katsuhito
K
Nishizawa
Yoshiki
Y
D000199:Actins / Q000378:metabolism; D028341:Activins / Q000494:pharmacology; D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D001665:Binding Sites; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000502:physiology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D005822:Genetic Vectors; D017228:Hepatocyte Growth Factor / Q000494:pharmacology; D006801:Humans; D028322:Inhibin-beta Subunits / Q000494:pharmacology; D007328:Insulin / Q000096:biosynthesis*; D007515:Islets of Langerhans / Q000166:cytology* / Q000378:metabolism; D008840:Microfilament Proteins; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology; D020218:Response Elements; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured; D000096985:Calponins
D000199:Actins; D028341:Activins; D002135:Calcium-Binding Proteins; D017228:Hepatocyte Growth Factor; D028322:Inhibin-beta Subunits; D007328:Insulin; D008840:Microfilament Proteins; D011994:Recombinant Proteins; D000096985:Calponins; C422405:activin A