α-Actinin TvACTN3 of Trichomonas vaginalis Is an RNA-Binding Protein That Could Participate in Its Posttranscriptional Iron Regulatory Mechanism

Table 3

Putative motifs present in tvactn3 that may be involved in DNA-RNA interactions.

Domain	Sequence^a	Consensus sequence/60%^b	Location aa*	GO Function	Reference
BRIGHT/ARID	VKSKLFNCIKFGRVVRPVIVDKRGVAMKTWGQ; LVTKCNSNGRPIPQVKEELLPPTLNLKFEEIEKT; ASDRRDELTKILEELQAKLINAFDEAANA	pppp.FbppLbpFbccptp...b.plPhls; .cs..lDLapLa.hVpcbGGbppVsps+p.; Wpclsppbsbss.......sssthpL+pbYb+bLbsaEpbbp.	292–386	DNA-binding	[32]
B5	PPTLNLKFEEIEKTASDRRDELTKILEELQAKLI; NAFDEAANAKIAVCDDINNKAINL	.pslplphsclscllGhsls.....pclhclLpcLG....; bplp.ps.....s.bpVplPsaR..hDlpbc....hDLlEEltRlaGY	344–401	RNA-binding,; Magnesium ion; binding, ATP; binding	[33]
LA	DDINNKAINLTGDLYEQRDALNNYLQQAQEAA; GTVKELQPQFVELVELRLNNRVKRT	pclppplb+QlEaYFScbNLspDbFLpcpbs; c..-GaVPlphlssFp+l+ sL*p-....hpbIspAL.+p S.....sblcls-c...sp+ lRRp..	392–448	RNA-binding	[34]
Pumilio-Binding	ELQPQFVELVELRLNNRVKRTVIAVDGEFEQLIATIK	.bpsplhplsp.cpaGspllQ+hlcbss.p...; pppbllp...	428–464	RNA-binding	[35–37]
KH	FVELVELRLNNRVKRTVIAVDGEFEQLIATIKRL; IEGNKAAIFEYENKKKIEEYNQAAQKYVDEVAQLKQ	..s.hpbpl..lss....pb htblIG+pG.; ..pslcplppps.ssplpl. p.............pphlpl pts....pslpbsbpbl.pblp....	433–502	RNA binding domain	[36–38]

aThe protein sequence of tvactn3 was used to search in the SMART 7 program to identify the presence of DNA-RNA binding putative domains in the aa sequence. The computational program used for this analysis presented the aa in a single word code. The other codes mean the following: (−) aa negatively charged: D or E; (*) aa S or T; (l) Aliphatic aa: I, L, V; (+) aa positive charged; (t) A, G, S aa; (a) aa with aromatic group: F, H, W, Y; (c) charged aa: D, E, H, K, R; (s) small aa: A, C, D, G, N, P, S, T, V; (p) polar aa: C, D, E, H, K, N, Q, R, S, T; (b) Big aa: E, F, H, I, K, L, M, Q, R, W, Y; (h) Hydrophobic aa: A, C, F, G, H, I, L, M, T, V, W, Y. ^bA PSI-BLAST search using the complete tvactn3 sequence (residues 1–1129) of T. vaginalis and 𝐸<0.01 enable us to identify each of the DNA-RNA binding domains sequences (BRIGHT/ARID, B5, LA, Pumilio-Binding, and KH domains) present in the DII of tvactn3 shown in Figure 8(d). These aa sequences showed a 60% similitude with the consensus sequences of these motifs by multiple alignments.