Cdt1 Self-associates via the Winged-Helix Domain of the Central Region during the Licensing Reaction, Which Is Inhibited by Geminin.
Biol Pharm Bull
; 47(7): 1338-1344, 2024.
Article
in En
| MEDLINE
| ID: mdl-39048355
ABSTRACT
The initiation of DNA replication is tightly controlled by the licensing system that loads replicative DNA helicases onto replication origins to form pre-replicative complexes (pre-RCs) once per cell cycle. Cdc10-dependent transcript 1 (Cdt1) plays an essential role in the licensing reaction by recruiting mini-chromosome maintenance (MCM) complexes, which are eukaryotic replicative DNA helicases, to their origins via direct protein-protein interactions. Cdt1 interacts with other pre-RC components, the origin recognition complex, and the cell division cycle 6 (Cdc6) protein; however, the molecular mechanism by which Cdt1 functions in the MCM complex loading process has not been fully elucidated. Here, we analyzed the protein-protein interactions of recombinant Cdt1 and observed that Cdt1 self-associates via the central region of the molecule, which is inhibited by the endogenous licensing inhibitor, geminin. Mutation of two ß-strands of the winged-helix domain in the central region of Cdt1 attenuated its self-association but could still interact with other pre-RC components and DNA similarly to wild-type Cdt1. Moreover, the Cdt1 mutant showed decreased licensing activity in Xenopus egg extracts. Together, these results suggest that the self-association of Cdt1 is crucial for licensing.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cell Cycle Proteins
/
Geminin
Limits:
Animals
/
Humans
Language:
En
Journal:
Biol Pharm Bull
Year:
2024
Document type:
Article