Literature summary for 2.7.7.19 extracted from

Bai, Y.; Srivastava, S.K.; Chang, J.H.; Manley, J.L.; Tong, L.
Structural basis for dimerization and activity of human PAPD1, a noncanonical poly(A) polymerase (2011), Mol. Cell, 41, 311-320.

Crystallization (Commentary)

Crystallization (Comment)	Organism
mutant D325A, to 3.1 A resolution. The overall structure of the palm and fingers domains is similar to that in the canonical poly(A) polymerases. The active site is located at the interface between the two domains, with a large pocket that can accommodate the substrates. The structure reveals a domain in the N-terminal region of PAPD1, with a backbone-fold that is similar to that of RNP-type RNA binding domains. This domain, together with a beta-arm insertion in the palm domain, contributes to dimerization of PAPD1. The crystal structure reveals a dimer, formed by the two molecules in the asymmetric unit	Homo sapiens

Crystallization (Comment)

Organism

mutant D325A, to 3.1 A resolution. The overall structure of the palm and fingers domains is similar to that in the canonical poly(A) polymerases. The active site is located at the interface between the two domains, with a large pocket that can accommodate the substrates. The structure reveals a domain in the N-terminal region of PAPD1, with a backbone-fold that is similar to that of RNP-type RNA binding domains. This domain, together with a beta-arm insertion in the palm domain, contributes to dimerization of PAPD1. The crystal structure reveals a dimer, formed by the two molecules in the asymmetric unit

Homo sapiens

Protein Variants

Protein Variants	Comment	Organism
D325A	mutation of one of the conserved Asp residues in the active site, complete loss of activity. The mutant protein gives better quality crystals than the wild-type enzyme	Homo sapiens
H259A/K260A/I261A	mutation in beta-arm, mutant remains dimeric	Homo sapiens
H259A/K260A/I261A/H294A/F295A/P297A	mutations simultaneously disrupt both areas of contact in the dimer interface, mutant is a stable monomer in solution, complete loss of activity	Homo sapiens
H294A/F295A/P297A	mutation in helix alphaE, mutant exists in a monomer-dimer equilibrium	Homo sapiens
Y221A/F222A	mutation in helix alphaB, mutant exists in a monomer-dimer equilibrium	Homo sapiens

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Mg2+	or Mn2+, required	Homo sapiens
Mn2+	or Mg2+, required	Homo sapiens

Organism

Organism	UniProt	Comment	Textmining
Homo sapiens	Q9NVV4	-	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
additional information	isoform PapD1 can utilize all four nucleotides as substrates, although it is more active with ATP or UTP. the lowest activity is observed with GTP	Homo sapiens	?	-	?

Subunits

Subunits	Comment	Organism
More	dimerization is required for the catalytic activity of isoform PAPD1	Homo sapiens

Synonyms

Synonyms	Comment	Organism
PapD1	-	Homo sapiens