The sequence analysis of the D.mel TIM50 presequence receptor paralogs suggest that they do not have phosphatase activity. - Attrill, H. (2026)
Trypanosoma brucei Tim50 have been shown to possesses phosphatase activity important for function (PMID:23212919). Human Tim50 has also been shown to have some phosphatase activity but it is not thought to be physiologically relevant (PMID:15044455). Other Tim50 orthologs have not been shown to possess phosphatase activity, lacking the canonical DxDxT active site motif associated with the prototypic Fcp1 phosophatase (PMID:12556522). Alignment of the CTD family of putative protein serine/threonine phosphatases shows that the Tim50 family members lack a DxDxT motif and are therefore members of the PSEUDOPHOSPHATASES gene group: FBgn0035124 ttm2 FBgn0032971 ttm3 FBgn0250874 ttm50 The candidates that do contain this motif and are therefore are placed in the CTD FAMILY PROTEIN SERINE/THREONINE PHOSPHATASES gene group: FBgn0035426 CG12078 FBgn0033322 CG8584 FBgn0029067 Ctdnep1 FBgn0035026 Fcp1 FBgn0027526 Ublcp1 FBgn0036556 hzg