Identification and characterization of xpac protein, the gene product of the human XPAC (xeroderma pigmentosum group A complementing) gene.
We have cloned human xeroderma pigmentosum group A complementing (XPAC) cDNA that encodes a "zinc finger" protein with a predicted size of 31 kDa. To detect the xpac protein in cells, we raised antibody against a recombinant human xpac protein. Using this antibody, we identified the xpac protein in the nucleus of cells. In normal human cells, 40- and 38-kDa proteins were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A reduced amount of the smaller protein was detected in XP 39OSSV cells, which show low UV sensitivity, and no xpac proteins were detected in XP 2OSSV cells, which show high UV sensitivity. These levels of xpac proteins in xeroderma pigmentosum cells were determinants of heterogeneity of the DNA repair defect in group A xeroderma pigmentosum. Synthesis of the xpac protein did not increase after UV irradiation.
Institute for Molecular and Cellular Biology, Osaka University, Japan.
N
N
Miura
I
I
Miyamoto
H
H
Asahina
I
I
Satokata
K
K
Tanaka
Y
Y
Okada
D015153:Blotting, Western; D002460:Cell Line / Q000528:radiation effects; D004247:DNA / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006801:Humans; D011233:Precipitin Tests; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D014466:Ultraviolet Rays; D014983:Xeroderma Pigmentosum / Q000235:genetics*; D051760:Xeroderma Pigmentosum Group A Protein; D016335:Zinc Fingers / Q000235:genetics
D004268:DNA-Binding Proteins; D012333:RNA, Messenger; C497314:XPA protein, human; D051760:Xeroderma Pigmentosum Group A Protein; D004247:DNA