Identification of a mitochondrial superoxide dismutase with an unusual targeting sequence in Plasmodium falciparum

Natasha Sienkiewicz; Wassim Daher; Daniel Dive; Carsten Wrenger; Eric Viscogliosi; René Wintjens; Helène Jouin; Monique Capron; Sylke Müller; Jamal Khalife

doi:10.1016/j.molbiopara.2004.05.005

Identification of a mitochondrial superoxide dismutase with an unusual targeting sequence in Plasmodium falciparum

Mol Biochem Parasitol. 2004 Sep;137(1):121-32. doi: 10.1016/j.molbiopara.2004.05.005.

Authors

Natasha Sienkiewicz¹, Wassim Daher, Daniel Dive, Carsten Wrenger, Eric Viscogliosi, René Wintjens, Helène Jouin, Monique Capron, Sylke Müller, Jamal Khalife

Affiliation

¹ Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, WTB/MSI Complex, DD15EH, UK.

PMID: 15279958
DOI: 10.1016/j.molbiopara.2004.05.005

Abstract

The intraerythrocytic stages of Plasmodium falciparum are exposed to oxidative stress and require functional anti-oxidant systems to survive. In addition to the parasite's known iron-dependent superoxide dismutase PfSOD1, a second SOD gene (PfSOD2) interrupted by 8 introns was identified on chromosome 6. Molecular modelling shows that the structure of PfSOD2 is similar to other iron-dependent SODs and phylogenetic analysis suggests PfSOD1 and PfSOD2 are the result of an ancestral gene duplication. The deduced amino acid sequence of PfSOD2 is similar to PfSOD1 but has a long N-terminal extension. Immunofluorescence studies show that PfSOD1 is cytosolic, whereas the N-terminal extension of PfSOD2 targets a green fluorescent protein fusion into the parasite's mitochondrion. Both SOD genes are transcribed during the erythrocytic cycle with PfSOD1 mRNA levels up to 35-fold higher than those of PfSOD2. Northern blots demonstrated that the mRNA levels of both SOD genes are up-regulated upon exposure to oxidative stress.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adaptation, Psychological
Amino Acid Sequence
Animals
Cytoplasm / enzymology
DNA, Complementary
DNA, Protozoan / chemistry
Erythrocytes / parasitology
Fluorescent Antibody Technique, Indirect
Gene Duplication
Gene Expression Regulation
Introns / genetics
Mitochondria / enzymology*
Models, Molecular
Molecular Sequence Data
Oxidative Stress
Phylogeny
Plasmodium falciparum / enzymology*
Plasmodium falciparum / genetics
Plasmodium falciparum / growth & development
Protein Sorting Signals*
Protein Transport*
RNA, Messenger / analysis
RNA, Protozoan / analysis
Recombinant Fusion Proteins / metabolism
Sequence Analysis, DNA
Sequence Homology
Superoxide Dismutase / chemistry*
Superoxide Dismutase / genetics*
Superoxide Dismutase / metabolism
Superoxide Dismutase-1

Substances

DNA, Complementary
DNA, Protozoan
Protein Sorting Signals
RNA, Messenger
RNA, Protozoan
Recombinant Fusion Proteins
Superoxide Dismutase
Superoxide Dismutase-1
superoxide dismutase 2

Associated data

GENBANK/AY586514