Plasmodium falciparum RUVBL3 protein: a novel DNA modifying enzyme and an interacting partner of essential HAT protein MYST

Abstract

RUVBLs constitute a conserved group of ATPase proteins that play significant role in a variety of cellular processes including transcriptional regulation, cell cycle and DNA damage repair. Three RUVBL homologues, namely, PfRUVBL1, PfRUVBL2 and PfRUVBL3 have been identified in P. falciparum, unlike its eukaryotic counterparts, which have two RUVBL proteins (RUVBL1 & RUVBL2). The present study expands our understanding of PfRUVBL3 protein and thereby basic biology of Plasmodium in general. Here, we have shown that parasite PfRUVBL3 is a true homolog of human/yeast RUVBL2 protein. Our result show that PfRUVBL3 constitutively expresses throughout the stages of intra-erythrocytic cycle (IDC) with varied localization. In addition to ATPase and oligomerization activity, we have for the first time shown that PfRUVBL3 possess DNA cleavage activity which interestingly is dependent on its insertion domain. Furthermore, we have also identified RUVBL3 to be an interacting partner of an essential chromatin remodeling protein PfMYST and together they colocalize with H3K9me1 histone in parasitophorous vacuole during the ring stage of IDC suggesting their potential involvement in chromatin remodeling and gene transcription.

Diversity-oriented synthesis derived indole based spiro and fused small molecules kills artemisinin-resistant Plasmodium falciparum

“…For routine culture, haematocrit was maintained at 5% and the stages and growth of parasite was routinely monitored by microscopic examination of Giemsa-stained blood smears. Synchronization of parasite culture was done using 5% sorbitol method as discussed elsewhere [ 30 ].…”

Plasmodium falciparum R2TP complex: driver of parasite Hsp90 function

“…2 0 0 9 ) : P F 3 D 7 _ 0 8 0 9 7 0 0 ( P f R U V B L 1 ) , PF3D7_1106000 (PfRUVBL2), and PF3D7_1362200 (PfRUVBL3). Sequence analysis has shown that PfRUVBL1 and PfRUVBL2 proteins are closer to yeast and human Rvb1/RUVBL1, whereas PfRUVBL3 is closer to Rvb2/RUVBL2 (Ahmad et al 2012(Ahmad et al , 2013Tuteja 2013a, 2013b;Sen et al 2018). The similarity between PfRUVBL3 and yeast Rvb2 has been demonstrated, since it was able to complement Rvb2 functions in yeast (Sen et al 2018).…”

“…Sequence analysis has shown that PfRUVBL1 and PfRUVBL2 proteins are closer to yeast and human Rvb1/RUVBL1, whereas PfRUVBL3 is closer to Rvb2/RUVBL2 (Ahmad et al 2012(Ahmad et al , 2013Tuteja 2013a, 2013b;Sen et al 2018). The similarity between PfRUVBL3 and yeast Rvb2 has been demonstrated, since it was able to complement Rvb2 functions in yeast (Sen et al 2018). Interestingly, PfRUVBL1 has a longer N-terminal region in comparison with its human and yeast orthologues, yet its functional role is unknown (Ahmad and Tuteja 2013a).…”

“…c Cryo-electron microscopy structure of the human R2TP complex (EMDB ID: EMD-4290). RPAP3 domains are shown in blue; RUVBL1 and RUVBL2 are colored in orange and green, respectively; PIH1D1 is shown in red malaria parasite (Ahmad et al 2012;Ahmad and Tuteja 2013b;Sen et al 2018). PfRUVBL1 has been shown as an active ATPase in the absence and, more robustly, in the presence of singlestranded DNA (ssDNA).…”

“…In contrast, PfRUVBL2 showed ATPase activity only in the presence of ssDNA and a weak helicase activity (Ahmad and Tuteja 2013b). PfRUVBL3 has been found as hexamers and also had ATPase activity but, unlike PfRUVBL1 and PfRUVBL2, PfRUVBL3 ATPase was stimulated by doublestranded DNA (dsDNA) and the recombinant protein did not show helicase activity (Ahmad and Tuteja 2013b;Sen et al 2018). The deletion of PfRUVBL3 domain II increased the ATPase activity of the protein, suggesting a regulatory role for this domain (Sen et al 2018).…”