TY - JOUR
T1 - Trichomonas vaginalis Repair of Iron Centres Proteins
T2 - The Different Role of Two Paralogs
AU - Nobre, Lígia S.
AU - Meloni, Dionigia
AU - Teixeira, Miguel
AU - Viscogliosi, Eric
AU - Saraiva, Lígia M.
PY - 2016/6/1
Y1 - 2016/6/1
N2 - Trichomonas vaginalis, the causative parasite of one of the most prevalent sexually transmitted diseases is, so far, the only protozoan encoding two putative Repair of Iron Centres (RIC) proteins. Homologs of these proteins have been shown to protect bacteria from the chemical stress imposed by mammalian immunity. In this work, the biochemical and functional characterisation of the T. vaginalis RICs revealed that the two proteins have different properties. Expression of ric1 is induced by nitrosative stress but not by hydrogen peroxide, while ric2 transcription remained unaltered under similar conditions. T. vaginalis RIC1 contains a di-iron centre, but RIC2 apparently does not. Only RIC1 resembles bacterial RICs on spectroscopic profiling and repairing ability of oxidatively-damaged iron-sulfur clusters. Unexpectedly, RIC2 was found to bind DNA plasmid and T. vaginalis genomic DNA, a function proposed to be related with its leucine zipper domain. The two proteins also differ in their cellular localization: RIC1 is expressed in the cytoplasm only, and RIC2 occurs both in the nucleus and cytoplasm. Therefore, we concluded that the two RIC paralogs have different roles in T. vaginalis, with RIC2 showing an unprecedented DNA binding ability when compared with all other until now studied RICs.
AB - Trichomonas vaginalis, the causative parasite of one of the most prevalent sexually transmitted diseases is, so far, the only protozoan encoding two putative Repair of Iron Centres (RIC) proteins. Homologs of these proteins have been shown to protect bacteria from the chemical stress imposed by mammalian immunity. In this work, the biochemical and functional characterisation of the T. vaginalis RICs revealed that the two proteins have different properties. Expression of ric1 is induced by nitrosative stress but not by hydrogen peroxide, while ric2 transcription remained unaltered under similar conditions. T. vaginalis RIC1 contains a di-iron centre, but RIC2 apparently does not. Only RIC1 resembles bacterial RICs on spectroscopic profiling and repairing ability of oxidatively-damaged iron-sulfur clusters. Unexpectedly, RIC2 was found to bind DNA plasmid and T. vaginalis genomic DNA, a function proposed to be related with its leucine zipper domain. The two proteins also differ in their cellular localization: RIC1 is expressed in the cytoplasm only, and RIC2 occurs both in the nucleus and cytoplasm. Therefore, we concluded that the two RIC paralogs have different roles in T. vaginalis, with RIC2 showing an unprecedented DNA binding ability when compared with all other until now studied RICs.
KW - Iron-sulfur repair
KW - Leucine zipper
KW - Nitrosative stress
KW - RIC
KW - Trichomonas vaginalis
KW - YtfE
UR - http://www.scopus.com/inward/record.url?scp=84964409718&partnerID=8YFLogxK
U2 - 10.1016/j.protis.2016.03.001
DO - 10.1016/j.protis.2016.03.001
M3 - Article
AN - SCOPUS:84964409718
SN - 1434-4610
VL - 167
SP - 222
EP - 233
JO - Protist
JF - Protist
IS - 3
ER -