Expression of calmodulin and calmodulin binding proteins in rat fibroblasts stably transfected with protein kinase C and oncogenes

TY - JOUR

T1 - Expression of calmodulin and calmodulin binding proteins in rat fibroblasts stably transfected with protein kinase C and oncogenes

AU - Ye, Q

AU - Wei, Y

AU - Fischer, R

AU - Borner, C

AU - Berchtold, M W

N1 - Keywords: Animals; Blotting, Northern; Calcium; Calmodulin; Calmodulin-Binding Proteins; Cell Line; Cell Line, Transformed; Cell Transformation, Neoplastic; DNA Probes; Egtazic Acid; Fibroblasts; Gene Expression Regulation; Isoenzymes; Oncogenes; Protein Kinase C; RNA, Messenger; Rats; Transcription, Genetic; Transfection

PY - 1997

Y1 - 1997

N2 - Molecular mechanisms leading to elevated calmodulin (CaM) expression in cancer have not yet been discovered. We have quantitated the levels of transcripts derived from all three CaM genes in a variety of the same origin rat fibroblasts transformed with oncogenes in combination with gene for protein kinase C using Northern blot analysis with three CaM gene specific cDNA probes. Five species of CaM mRNA were detected in all these cells. Surprisingly many of the investigated cell lines exhibited a decreased content of all CaM mRNAs as compared to control cells with CaMI and CaMII transcripts showing the most pronounced alterations. In contrast, CaM protein levels were increased in all these cell lines as determined by a radioimmunoassay. These results suggest that oncogenic up-regulation of CaM synthesis takes place posttranscriptionally. Several CaM binding proteins were found at different concentrations in the studied cell lines depending on the oncogenes used for transformation. However, CaM overexpression does not seem to affect the overall levels of CaM binding proteins.

AB - Molecular mechanisms leading to elevated calmodulin (CaM) expression in cancer have not yet been discovered. We have quantitated the levels of transcripts derived from all three CaM genes in a variety of the same origin rat fibroblasts transformed with oncogenes in combination with gene for protein kinase C using Northern blot analysis with three CaM gene specific cDNA probes. Five species of CaM mRNA were detected in all these cells. Surprisingly many of the investigated cell lines exhibited a decreased content of all CaM mRNAs as compared to control cells with CaMI and CaMII transcripts showing the most pronounced alterations. In contrast, CaM protein levels were increased in all these cell lines as determined by a radioimmunoassay. These results suggest that oncogenic up-regulation of CaM synthesis takes place posttranscriptionally. Several CaM binding proteins were found at different concentrations in the studied cell lines depending on the oncogenes used for transformation. However, CaM overexpression does not seem to affect the overall levels of CaM binding proteins.

U2 - 10.1016/S0167-4889(97)00086-4

DO - 10.1016/S0167-4889(97)00086-4

M3 - Journal article

C2 - 9398089

SN - 0167-4889

VL - 1359

SP - 89

EP - 96

JO - Biochimica et Biophysica Acta - Molecular Cell Research

JF - Biochimica et Biophysica Acta - Molecular Cell Research

IS - 1

ER -