TY - JOUR
T1 - A tyrosyl DNA phosphodiesterase 1 from kinetoplastid parasite Leishmania donovani (LdTdp1) capable of removing topo I-DNA covalent complexes
AU - Banerjee, Bijoylaxmi
AU - Roy, Amit
AU - Sen, Nilkantha
AU - Majumder, Hemanta K.
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2010/10
Y1 - 2010/10
N2 - Tyrosyl DNA phosphodiesterase 1 (Tdp1) is a member of phospholipase D superfamily, which cleaves a broad range of 3′-DNA adducts, the best characterized of which is the phosphodiester bond formed between DNA and topoisomerase IB. This study describes cloning and functional characterization of the enzyme, termed as LdTdp1 in the kinetoplastid parasite Leishmania donovani. Sequence analysis confirmed conservation of the active site motifs typical for all Tdp1 proteins. LdTdp1 activity was detected in the parasite nucleus as well as in the kinetoplast. The enzyme harbours a nuclear localization signal at its C-terminus. Overexpression of the active enzyme protected the parasites against topoisomerase IB inhibitor camptothecin (CPT) and oxidative agent H 2O 2-mediated cytotoxicity and its downregulation rendered the parasites hypersensitive to CPT. Trapping of mutant LdTdp1 on DNA takes place following CPT treatment in L. donovani cells. The expression level and associated activity of LdTdp1 were found to be higher in CPT-resistant L. donovani parasites. Altogether, this is the first report of Tdp1 from the kinetoplastid parasite L. donovani, which actively participates in topoisomerase I-mediated DNA damage repair process and thereby counteracts the cytotoxic effect of topoisomerase I inhibitors.
AB - Tyrosyl DNA phosphodiesterase 1 (Tdp1) is a member of phospholipase D superfamily, which cleaves a broad range of 3′-DNA adducts, the best characterized of which is the phosphodiester bond formed between DNA and topoisomerase IB. This study describes cloning and functional characterization of the enzyme, termed as LdTdp1 in the kinetoplastid parasite Leishmania donovani. Sequence analysis confirmed conservation of the active site motifs typical for all Tdp1 proteins. LdTdp1 activity was detected in the parasite nucleus as well as in the kinetoplast. The enzyme harbours a nuclear localization signal at its C-terminus. Overexpression of the active enzyme protected the parasites against topoisomerase IB inhibitor camptothecin (CPT) and oxidative agent H 2O 2-mediated cytotoxicity and its downregulation rendered the parasites hypersensitive to CPT. Trapping of mutant LdTdp1 on DNA takes place following CPT treatment in L. donovani cells. The expression level and associated activity of LdTdp1 were found to be higher in CPT-resistant L. donovani parasites. Altogether, this is the first report of Tdp1 from the kinetoplastid parasite L. donovani, which actively participates in topoisomerase I-mediated DNA damage repair process and thereby counteracts the cytotoxic effect of topoisomerase I inhibitors.
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U2 - 10.1111/j.1365-2958.2010.07318.x
DO - 10.1111/j.1365-2958.2010.07318.x
M3 - Article
C2 - 20659295
AN - SCOPUS:77957233906
SN - 0950-382X
VL - 78
SP - 119
EP - 137
JO - Molecular Microbiology
JF - Molecular Microbiology
IS - 1
ER -