Regulation of alpha 1b-adrenergic receptor gene expression in rat liver cell lines.
alpha 1b-Adrenergic receptor gene expression was investigated in two rat hepatic cell lines, Clone 9 and McA-RH7777 cells. By Northern blot analysis, Clone 9 cells expressed a 2.7 kb alpha 1b-adrenergic receptor gene transcript whereas two transcripts, 3.3 kb and 2.7 kb, were observed in total cellular RNA isolated from rat liver. A binding site for the alpha 1-adrenergic antagonist [3H]prazosin was observed in Clone 9 cell membrane preparations (Bmax = 47 +/- 7 fmol/mg protein and Kd = 0.11 +/- 0.02 nM, n = 5). In contrast, alpha 1b-adrenergic receptor gene transcripts could not be detected in total cellular RNA prepared from McA-RH7777 cells by either Northern blot analysis or ribonuclease protection assays. However, results from nuclear run-off assays indicated that the alpha 1b-adrenergic receptor gene was transcribed in McA-RH7777 cells and alpha 1b-adrenergic receptor gene transcripts were observed in McA-RH7777 cell nuclear RNA. These results suggest that alpha 1b-adrenergic receptor gene expression in liver may be regulated in part post-transcriptionally and that this level of regulation may be altered or disrupted in the Clone 9 and McA-RH7777 cell lines.
Deng
C L
CL
Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock 72205-7199.
Cornett
L E
LE
D000818:Animals; D002451:Cell Compartmentation; D002999:Clone Cells; D003513:Cycloheximide / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D008099:Liver / Q000378:metabolism*; D011224:Prazosin / Q000494:pharmacology; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D011869:Radioligand Assay; D051381:Rats; D017207:Rats, Sprague-Dawley; D018340:Receptors, Adrenergic, alpha-1 / Q000235:genetics*; D014158:Transcription, Genetic
C547718:Adra1b protein, rat; D012333:RNA, Messenger; D018340:Receptors, Adrenergic, alpha-1; D003513:Cycloheximide; D011224:Prazosin