Phosphatase Family SSU72

Phosphatase Classification: Superfamily CC2: Family SSU72

Evolution

Ssu72 can be found in all the unikonts (animals, choanoflagellates, fungi, and amoebozoan), plants/algae, Heterokonts, Trichomonas vaginalis (but not Giardia or Trypanasoma or Leishmania). Most SSU72 consist almost entirely of the phosphatase domain.

Function

The phosphatase activity of Ssu72 is important for Pol II transcription and termination and for gene looping. It catalyzes CTD Serine-5 dephosphorylation in association with the Pta1 component of the CPF complex. In yeast, Ssu72 is required for pre-mRNA 3’-end cleavage, but so far no evidence exists implicating mammalian Ssu72 in that processing [1] [2].

Reference

1. Krishnamurthy S, He X, Reyes-Reyes M, Moore C, and Hampsey M. Ssu72 Is an RNA polymerase II CTD phosphatase. Mol Cell. 2004 May 7;14(3):387-94. DOI:10.1016/s1097-2765(04)00235-7 |
2. Xiang K, Nagaike T, Xiang S, Kilic T, Beh MM, Manley JL, and Tong L. Crystal structure of the human symplekin-Ssu72-CTD phosphopeptide complex. Nature. 2010 Oct 7;467(7316):729-33. DOI:10.1038/nature09391 |