Premium
The increase of calmodulin in PC12 cells induced by NGF is caused by differential expression of multiple mRNAs for calmodulin
Author(s) -
Bai Guang,
Weiss Benjamin
Publication year - 1991
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1041490309
Subject(s) - calmodulin , microbiology and biotechnology , calmodulin binding proteins , messenger rna , chemistry , biology , biochemistry , enzyme , gene
A rat pheochromocytoma cell line (PC12 cells) was used as a model to investigate the role of calmodulin and its multiple mRNAs in NGF‐induced neuronal differentiation. The effect of NGF on the degree of differentiation was assayed using a simple differentiation scoring system. Significant increases in the differentiation score were seen by one day, and the scores increased about 10‐fold by 8 days of treatment. NGF also increased calmodulin in the PC12 cells; significant increases were seen by 2 days of treatment, and a maximum increase of 3‐fold was seen by 4 days. Northern blot analysis using a calmodulin riboprobe revealed that all five calmodulin mRNAs found in rat tissue were present in PC12 cells. The relative abundance of the calmodulin mRNAs was 1.7 ≥ 1.4 ≥ 2.3 ≥ 4.1 ≥ 0.9 kb. NGF treatment caused a differential increase in these mRNAs. The 1.4 kb transcript (from Gene II) was increased earlier (at 1 day) and to a greater extent (3‐fold) than any of the other mRNAs. Studies of the half‐lives (t 1/2 ) of these mRNAs suggested that the t1/2 varied with the mRNA; the smaller the mRNA, the shorter the t1/2. However, there were no significant effects of NGF on the t1/2 of any of the mRNAs. These studies indicate that NGF elevates calmodulin in PC12 cells by causing a differential increase in the multiple mRNAs for calmodulin and that the increase in calmodulin may play some part in NGF‐induced neuronal differentiation in PC12 cells.