TY - JOUR
T1 - Two human homologs of Rad23 are functionally interchangeable in complex formation and stimulation of XPC repair activity
AU - Sugasawa, Kaoru
AU - Ng, Jessica M.Y.
AU - Masutani, Chikahide
AU - Maekawa, Takafumi
AU - Uchida, Akio
AU - Van Der Spek, Peter J.
AU - Eker, André P.M.
AU - Rademakers, Suzanne
AU - Visser, Cécile
AU - Aboussekhra, Abdelilah
AU - Wood, Richard D.
AU - Hanaoka, Fumio
AU - Bootsma, Dirk
AU - Hoeijmakers, Jan H.J.
PY - 1997/12
Y1 - 1997/12
N2 - XPC-hHR23B protein complex is specifically involved in nucleotide excision repair (NER) of DNA lesions on transcriptionally inactive sequences as well as the nontranscribed strand of active genes. Here we demonstrate that not only highly purified recombinant hHR23B (rhHR23B) but also a second human homolog of the Saccharomyces cerevisiae Rad23 repair protein, hHR23A, stimulates the in vitro repair activity of recombinant human XPC (rhXPC), revealing functional redundancy between these human Rad23 homologs. Coprecipitation experiments with His-tagged rhHR23 as well as sedimentation velocity analysis showed that both rhHR23 proteins in vitro reconstitute a physical complex with rhXPC. Both complexes were more active than free rhXPC, indicating that complex assembly is required for the stimulation. rhHR23B was shown to stimulate an early stage of NER at or prior to incision. Furthermore, both rhHR23 proteins function in a defined NER system reconstituted with purified proteins, indicating direct involvement of hHR23 proteins in the DNA repair reaction via interaction with XPC.
AB - XPC-hHR23B protein complex is specifically involved in nucleotide excision repair (NER) of DNA lesions on transcriptionally inactive sequences as well as the nontranscribed strand of active genes. Here we demonstrate that not only highly purified recombinant hHR23B (rhHR23B) but also a second human homolog of the Saccharomyces cerevisiae Rad23 repair protein, hHR23A, stimulates the in vitro repair activity of recombinant human XPC (rhXPC), revealing functional redundancy between these human Rad23 homologs. Coprecipitation experiments with His-tagged rhHR23 as well as sedimentation velocity analysis showed that both rhHR23 proteins in vitro reconstitute a physical complex with rhXPC. Both complexes were more active than free rhXPC, indicating that complex assembly is required for the stimulation. rhHR23B was shown to stimulate an early stage of NER at or prior to incision. Furthermore, both rhHR23 proteins function in a defined NER system reconstituted with purified proteins, indicating direct involvement of hHR23 proteins in the DNA repair reaction via interaction with XPC.
UR - http://www.scopus.com/inward/record.url?scp=0030688064&partnerID=8YFLogxK
U2 - 10.1128/MCB.17.12.6924
DO - 10.1128/MCB.17.12.6924
M3 - Article
C2 - 9372924
AN - SCOPUS:0030688064
SN - 0270-7306
VL - 17
SP - 6924
EP - 6931
JO - Molecular and Cellular Biology
JF - Molecular and Cellular Biology
IS - 12
ER -