Testis-expressed protein 10 (TEX10) is a vertebrate protein and a component of the Five Friends of Methylated CHTOP (5FMC) [], PELP1 []and MLL1/MLL []complexes. Pre-rRNA-processing protein Ipi1 is found in fungi and is a component of the RIX1 complex, which is a critical determinant of DNA replication licensing [].
SENP5 peptidase (sentrin-specific peptidase 5, MEROPS identifier C48.008) is a deSUMOylating peptidase localized predominantly to the nucleolus. SENP5 releases the tag proteins SUMO-2 and -3 from conjugates, preferentially acting as an isopeptidase rather than an endopeptidase []. Simultaneous depletion of SENP3 and SENP5 results in enhanced SUMOylation of proteins such as RPL37A and GNL2, which are involved in the processing of pre-rRNA [], PELP1 and LAS1L, which are involved in the release of mature ribosomal particles [], and Nop58, which is a component of small nucleolar ribonucleoprotein (snoRNP) and SUMOlyation is required for binding of Nop58 to snoRNA to maintain nucleolar retention []. SENP5 depletion also affects mitotic progression, and cells arrest at the G2/M transition []. SENP5 is also involved in mitochondrial fusion and fission, because SUMOylated dynamin-1-like protein (Drp1), which is a mitochondrial fission factor, is a target for SENP5 []. DeSUMOylation of Drp1 is a contributory factor to cardiomyopathy []. During the G2/M transition stage of mitosis, SENP5 transiently locates to the mitochondrion []. SENP5 is also required for neutrophil differentiation, and the SNP5 gene is repressed in clinical acute myeloid leukemia [].
