Induction of apoptosis by Elk-1 and deltaElk-1 proteins.
Elk-1, an ets related gene codes for at least two splice variants Elk-1, which regulates c-fos transcription and deltaElk-1, both of which function as transcriptional activators. To investigate the role of Elk-1 and deltaElk-1 proteins in apoptosis; we have developed rat fibroblast cell lines and human breast cancer cell lines expressing Elk-1 and deltaElk-1. The expression of Elk-1 and deltaElk-1 proteins in the Elk-1/deltaElk-1 transfectants were analysed by immunofluorescence, immunohistochemistry, and Western blot analysis. The Elk-1 unlike deltaElk-1 transfectants showed a shortened and flattened morphology compared to the parental cells. We have found that calcium ionophore treatment of Rat-1 Elk-1, MCF-7 Elk-1, Rat-1 deltaElk-1 and MCF-7 deltaElk-1 transfectants resulted in programmed cell death. These results indicate that constitutive expression of Elk-1 and deltaElk-1 proteins triggers apoptosis in Rat-1 fibroblasts and breast cancer cells when treated with calcium ionophore.
Department of Human Genetics, Allegheny University of the Health Sciences, Philadelphia, Pennsylvania 19102, USA.
N
N
Shao
Y
Y
Chai
J Q
JQ
Cui
N
N
Wang
K
K
Aysola
E S
ES
Reddy
V N
VN
Rao
D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D004268:DNA-Binding Proteins; D005260:Female; D006801:Humans; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology*; D051381:Rats; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014407:Tumor Cells, Cultured; D050807:ets-Domain Protein Elk-1
D004268:DNA-Binding Proteins; C494112:ELK1 protein, human; C494114:Elk1 protein, rat; D011518:Proto-Oncogene Proteins; D014157:Transcription Factors; D050807:ets-Domain Protein Elk-1