Mouse RAD50 has limited epitopic homology to p53 and is expressed in the adult myocardium.
Previous studies have identified a 180-kDa mouse cardiomyocyte phosphoprotein with limited epitopic homology to p53. In this study, the protein was purified and partially sequenced. Oligonucleotide probes based on the available amino acid sequence data were used to isolate cDNA clones. Sequence analyses revealed that the clones encoded a protein with regional homology to the yeast RAD50 gene product. Expression of the mouse cDNA rescued the methyl methanesulfonate-sensitive phenotype in rad50 mutant yeast, indicating that the cardiomyocyte phosphoprotein is the mammalian homologue of the yeast RAD50 gene product. Fluorescence in situ hybridization analyses localized the mouse RAD50 gene to the A5-B1 region of chromosome 11. Northern blot analyses demonstrated a complex pattern of RAD50 expression during mouse development which was further complicated by the presence of several alternatively spliced transcripts. High levels of RAD50 expression was evident in the adult myocardium, a somewhat surprising observation given the absence of DNA synthesis in adult cardiomyocytes.
Kim
K K
KK
Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, Indiana 46202-4800, USA.
Daud
A I
AI
Wong
S C
SC
Pajak
L
L
Tsai
S C
SC
Wang
H
H
Henzel
W J
WJ
Field
L J
LJ
D016475:3T3 Cells; D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D000939:Epitopes / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008809:Mice, Inbred C3H; D008969:Molecular Sequence Data; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D016159:Tumor Suppressor Protein p53 / Q000276:immunology*
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D000939:Epitopes; D005656:Fungal Proteins; C086930:RAD50 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D016159:Tumor Suppressor Protein p53