Abstract
Truncated and full-length epidermal growth factor (EGF) receptors are produced in rat liver cells. The truncated EGF receptor mRNA is almost identical to the full-length EGF receptor mRNA except for the lack of a 3' region of the full-length receptor mRNA. To understand the stability of rat EGF receptor mRNAs, we analyzed the expression of EGF receptor mRNAs in the hepatoma cell line, AH66 and liver cells. Ten, 7 and 5kb full-length and 2.7kb truncated EGF receptor mRNAs were detected in both of them. The half-lives of the 10 and 2.7kb EGF receptor mRNAs were determined in AH66 cells using a transcriptional inhibitor, 5, 6-dichlororibofuranosylbenzimidazole. The half-lives of the 10 and 2.7kb mRNAs were 1.2 and 11h, respectively. These results indicated that the truncated mRNA is 4 times more stable than the full-length mRNA in rat cells. As for the stability, the role of a sequence of 3'-untranslated region of the EGF receptor mRNA was discussed.