1RJG: Structure Of Ppm1, A Leucine Carboxy Methyltransferase Involved In The Regulation Of Protein Phosphatase 2a Activity

The important role of the serine/threonine protein phosphatase 2A (PP2A) in various cellular processes requires a precise and dynamic regulation of PP2A activity, localization, and substrate specificity. The regulation of the function of PP2A involves the reversible methylation of the COOH group of the C-terminal leucine of the catalytic subunit, which, in turn, controls the enzyme's heteromultimeric composition and confers different protein recognition and substrate specificity. We have determined the structure of PPM1, the yeast methyltransferase responsible for methylation of PP2A. The structure of PPM1 reveals a common S-adenosyl-l-methionine-dependent methyltransferase fold, with several insertions conferring the specific function and substrate recognition. The complexes with the S-adenosyl-l-methionine methyl donor and the S-adenosyl-l-homocysteine product and inhibitor unambiguously revealed the co-substrate binding site and provided a convincing hypothesis for the PP2A C-terminal peptide binding site. The structure of PPM1 in a second crystal form provides clues to the dynamic nature of the PPM1/PP2A interaction.
PDB ID: 1RJGDownload
MMDB ID: 25486
PDB Deposition Date: 2003/11/19
Updated in MMDB: 2003/12
Experimental Method:
x-ray diffraction
Resolution: 2.61  Å
Source Organism:
Similar Structures:
Biological Unit for 1RJG: monomeric; determined by author
Molecular Components in 1RJG
Label Count Molecule
Protein (1 molecule)
Carboxy Methyl Transferase for Protein Phosphatase 2A Catalytic Subunit(Gene symbol: PPM1)
Molecule annotation
Chemical (1 molecule)
* Click molecule labels to explore molecular sequence information.

Citing MMDB