2GAF

Crystal Structure of the Vaccinia Polyadenylate Polymerase Heterodimer (apo form)

Summary for 2GAF

• Entry DOI: 10.2210/pdb2gaf/pdb
• Related: 2GA9
• Descriptor: Cap-specific mRNA (nucleoside-2'-O-)-methyltransferase, Poly(A) polymerase catalytic subunit (3 entities in total)
• Functional Keywords: polyadenylate polymerase, pox virus, nucleotidyltransferase, heterodimer, processivity, transferase
• Biological source: Vaccinia virus; More
• Total number of polymer chains: 2
• Total formula weight: 89446.75

Authors

Moure, C.M.,Bowman, B.R.,Gershon, P.D.,Quiocho, F.A. (deposition date: 2006-03-08, release date: 2006-05-16, Last modification date: 2024-10-09)

Primary citation

Moure, C.M.,Bowman, B.R.,Gershon, P.D.,Quiocho, F.A.
Crystal structures of the vaccinia virus polyadenylate polymerase heterodimer: insights into ATP selectivity and processivity.
Mol.Cell, 22:339-349, 2006

PubMed Abstract: Polyadenylation of mRNAs in poxviruses, crucial for virion maturation, is carried out by a poly(A) polymerase heterodimer composed of a catalytic component, VP55, and a processivity factor, VP39. The ATP-gamma-S bound and unbound crystal structures of the vaccinia polymerase reveal an unusual architecture for VP55 that comprises of N-terminal, central or catalytic, and C-terminal domains with different topologies and that differs from many polymerases, including the eukaryotic poly(A) polymerases. Residues in the active site of VP55, located between the catalytic and C-terminal domains, make specific interactions with the adenine of the ATP analog, establishing the molecular basis of ATP recognition. VP55's concave surface docks the globular VP39. A model for RNA primer binding that involves all three VP55 domains and VP39 is proposed. The model supports biochemical evidence that VP39 functions as a processivity factor by partially enclosing the RNA primer at the heterodimer interface.

PubMed: 16678106
DOI: 10.1016/j.molcel.2006.03.015

Experimental method

X-RAY DIFFRACTION (2.4 Å)