This domain is the bound prodomain fragment ProdP9 of the SUB1 protein present in Plasmodium falciparum. SUB1 is a serine protease that processes a subset of parasite proteins that play indispensable roles in egress and invasion. The C-terminal stalk of ProdP9 binds in the active site groove in a substrate-like manner and is truncated at the N terminus as a result of the chymotrypsin digestion step used during purification. ProdP9 is structural similar to MIC5 from Toxoplasma gondii, despite low sequence identity [].
This entry represents a group of RNA polymerase II transcriptional coactivators, including Sub1 from budding yeasts, Tcp4 from animals and KIWI/KELP from plants.Tcp4, also known as p15, is a coactivator that functions cooperatively with TAFs and mediates functional interactions between upstream activators and the general transcriptional machinery. It has a bipartite structure composed of an amino-terminal regulatory domain and a carboxy-terminal cryptic DNA-binding domain []. The DNA-binding activity of the carboxy-terminal is disguised by the amino-terminal p15 domain. Activity is controlled by protein kinases that target the regulatory domain.Sub1 facilitates elongation by influencing enzymes that modify RNAP II (RNA polymerase II) []. It is required for NHEJ repair of DSBs in plasmid DNA, but not in chromosomal DNA [].KELP has been shown to bind to movement protein (MP) of tomato mosaic virus (ToMV) and interferes with virus cell-to-cell movement [].
