Poly(A) RNA polymerase

spinqualitylabelsall models Cid1 complex with UTP (PDB code 4e80) Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Function Poly(A) RNA polymerase protein Cid1 (Caffeine-Induced Death protein 1) is involved in cell cycle arrest where it inhibits unscheduled mitosis. Cid1 is found in fission yeast. Cid1 exists in 3 forms: apo I consists of 4 subunits; apo II consists of 2 subunits; UTP-bound form consists of 4 subunits. Poly(A) RNA polymerase Gld2 is responsible for poly(A) tail lengthening. Gld2 activity in the brain is required for long-term memory. Structural highlights The UTP binding site of Cid1 is between the N-terminal and C-terminal. The active site contains the catalytic triad of aspartic acids (in magenta) in the N-terminal and the His residue (in cyan) whose two conformations select between binding of UTP and ATP to Cid1 . Water molecules are shown as red spheres.

3D Structures of poly(A) RNA polymerase

Updated on 02-June-2026

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• Poly(A) RNA polymerase Cid1
  • 4e7x, 4e8f – fyCid1 - fission yeast
    
  • 4ud4, 4ud5 – fyCid1 (mutant)
    
  • 4e80 – fyCid1 + UTP
    
  • 4fh3 – fyCid1 residues 33-377
    
  • 4ep7, 4fh5, 4fhp – fyCid1 residues 30-377 + UTP
    
  • 4fhv – fyCid1 residues 30-377 + CTP
    
  • 4fhw – fyCid1 residues 30-377 + GTP
    
  • 4fhy – fyCid1 residues 30-377 + ATP
    
  • 4fhx – fyCid1 residues 30-377 (mutant) + ATP
    
  • 4nkt – fyCid1 residues 30-377 + UMPNPP
    
  • 4nku – fyCid1 residues 40-377 (mutant) + dinucleotide
    
• Poly(A) RNA polymerase Gld2 or terminal nucleotidyltransferase 2
  • 6lbj - Gld2 residues 143-484 (mutant) – mouse
    
  • 6lbk - Gld2 residues 131-484 (mutant) – rat
    
  • 5jnb - CeGld2 residues 546-923 + RNP-8 – Caenorhabditis elegans
    
  • 4zrl – CeGld2 residues 527-923 + defective in germ line development protein
    
  • 3nyb - Gld2 residues 161-481 (mutant) + AIR2 – yeast
    
• Poly(A) RNA polymerase
  • 3pq1 – hPAP (mutant) - human
    

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