Molecular basis for DNA repair synthesis on short gaps by mycobacterial Primase-Polymerase C.

ABSTRACT: Cells utilise specialized polymerases from the Primase-Polymerase (Prim-Pol) superfamily to maintain genome stability. Prim-Pol's function in genome maintenance pathways including replication, repair and damage tolerance. Mycobacteria contain multiple Prim-Pols required for lesion repair, including Prim-PolC that performs short gap repair synthesis during excision repair. To understand the molecular basis of Prim-PolC's gap recognition and synthesis activities, we elucidated crystal structures of pre- and post-catalytic complexes bound to gapped DNA substrates. These intermediates explain its binding preference for short gaps and reveal a distinctive modus operandi called Synthesis-dependent Template Displacement (STD). This mechanism enables Prim-PolC to couple primer extension with templ

SUBMITTER: Brissett NC 

PROVIDER: S-EPMC7442782 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature