TY - JOUR
T1 - XPC-RAD23B enhances UV-DDB binding to DNA to facilitate lesion search in nucleotide excision repair
AU - An, Soyeong
AU - Kusakabe, Masayuki
AU - Kim, Hyun Suk
AU - Kozono, Hidetsugu
AU - Cheon, Na Young
AU - Kim, Jeongeun
AU - Kang, Jieun
AU - Jang, Sunbok
AU - Sugasawa, Kaoru
AU - Schärer, Orlando D.
AU - Lee, Ja Yil
N1 - Publisher Copyright:
© The Author(s) 2025.
PY - 2025/6/24
Y1 - 2025/6/24
N2 - Ultraviolet-induced DNA lesions are removed by the nucleotide excision repair (NER) pathway. In global-genome NER (GG-NER), XPC-RAD23B recognizes the lesions and initiates NER. However, cyclobutane pyrimidine dimers (CPDs), which do not significantly destabilize the DNA duplex, are not bound by XPC-RAD23B with high selectivity. Instead, CPD is preferentially sensed by UV-DDB, which is believed to hand over the lesion to XPC-RAD23B via ubiquitination of both proteins. Here, by combining biochemical and single-molecule DNA curtain assays, we investigate the interactions between UV-DDB and XPC-RAD23B on DNA. Surprisingly, we discover that XPC-RAD23B enhances the binding of UV-DDB to DNA. We demonstrate that this enhancement can be attributed to the complex formation of UV-DDB and XPC-RAD23B (UX-complex), which increases the binding affinity of UV-DDB to undamaged DNA. We further show that UV-DDB finds CPDs through one-dimensional (1D) diffusion along DNA. Collectively, the UX-complex enhances UV-DDB loading to DNA to accelerate the search for CPD via 1D diffusion. Moreover, we find that UV-DDB and XPC-RAD23B can bind CPDs as a complex, which facilitates the transfer of CPD. Altogether, our results show that UV-DDB and XPC-RAD23B cooperatively interact for rapid CPD search, providing a new mechanism for lesion search in GG-NER.
AB - Ultraviolet-induced DNA lesions are removed by the nucleotide excision repair (NER) pathway. In global-genome NER (GG-NER), XPC-RAD23B recognizes the lesions and initiates NER. However, cyclobutane pyrimidine dimers (CPDs), which do not significantly destabilize the DNA duplex, are not bound by XPC-RAD23B with high selectivity. Instead, CPD is preferentially sensed by UV-DDB, which is believed to hand over the lesion to XPC-RAD23B via ubiquitination of both proteins. Here, by combining biochemical and single-molecule DNA curtain assays, we investigate the interactions between UV-DDB and XPC-RAD23B on DNA. Surprisingly, we discover that XPC-RAD23B enhances the binding of UV-DDB to DNA. We demonstrate that this enhancement can be attributed to the complex formation of UV-DDB and XPC-RAD23B (UX-complex), which increases the binding affinity of UV-DDB to undamaged DNA. We further show that UV-DDB finds CPDs through one-dimensional (1D) diffusion along DNA. Collectively, the UX-complex enhances UV-DDB loading to DNA to accelerate the search for CPD via 1D diffusion. Moreover, we find that UV-DDB and XPC-RAD23B can bind CPDs as a complex, which facilitates the transfer of CPD. Altogether, our results show that UV-DDB and XPC-RAD23B cooperatively interact for rapid CPD search, providing a new mechanism for lesion search in GG-NER.
UR - https://www.scopus.com/pages/publications/105008993067
U2 - 10.1093/nar/gkaf463
DO - 10.1093/nar/gkaf463
M3 - Article
C2 - 40530698
AN - SCOPUS:105008993067
SN - 0305-1048
VL - 53
JO - Nucleic Acids Research
JF - Nucleic Acids Research
IS - 11
M1 - gkaf463
ER -