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From Proteopedia

Poly(A) Polymerase (polynucleotide adenylytransferase, EC 2.7.7.19) is the enzyme responsible for adding a polyadenine tail to the 3' end of a nascent pre-mRNA transcript. Its substrates are ATP and RNA. The poly(A) tail that poly-A polymerase adds to the 3' end of the pre-mRNA transcript is important for nuclear export, translation and stability of the mRNA.

Determinants of ATP Recognition

This section complements the article on Poly(A) Polymerase in the Molecule of the Month Series. See also Teaching Scenes, Tutorials, and Educators' Pages.

3D structures of poly(A) polymerase

3aqk, 3aql, 3aqm, 3aqn – PAP residues 18-431 – Escherichia coli
1jsz - VvPAP regulatory subunit residues 1-307 – Vaccinia virus
1jte, 1eam - VvPAP regulatory subunit residues 1-307 (mutant)
2hhp, 2o1p – yPAP - yeast
1q79, 1f5a - bPAP-α - bovine

Poly(A) polymerase complex

3er8, 3er9, 3erc – VvPAP catalytic subunit + RNA
2ga9 - VvPAP catalytic subunit + CAP-specific mRNA methyltransferase + ATP
2gaf - VvPAP catalytic subunit (mutant) + CAP-specific mRNA methyltransferase
1jtf, 2vp3 - VvPAP regulatory subunit residues 1-307 (mutant) + M7GPPPG
1b42, 1bky, 1eqa, 3mag, 3mct, 4dcg, 1av6, 1p39, 1v39 - VvPAP regulatory subunit residues 1-297 (mutant) + purine derivative + adenosylhomocysteine
1vp3 - VvPAP regulatory subunit + adenosylhomocysteine
1vp9 - VvPAP regulatory subunit (mutant) + adenosylhomocysteine
1vpt - VvPAP regulatory subunit (mutant) + adenosylmethionine
3c66 - yPAP residues 1-526 + Fip1 peptide
2q66 – yPAP + polyA + ATP
1q78 – bPAP-α + Mg + ATP

Additional Resources

For additional information, see: Translation
For additional examples of transferases, see: Transferase

• PDB entry 2q66

Reference

Mechanism of poly(A) polymerase: structure of the enzyme-MgATP-RNA ternary complex and kinetic analysis., Balbo PB, Bohm A, Structure. 2007 Sep;15(9):1117-31. PMID:17850751