Plasmodium falciparum enolase: stage-specific expression and sub-cellular localization.
BACKGROUND
In an earlier study, it was observed that the vaccination with Plasmodium falciparum enolase can confer partial protection against malaria in mice. Evidence has also build up to indicate that enolases may perform several non-glycolytic functions in pathogens. Investigating the stage-specific expression and sub-cellular localization of a protein may provide insights into its moonlighting functions.


METHODS
Sub-cellular localization of P. falciparum enolase was examined using immunofluorescence assay, immuno-gold electron microscopy and western blotting.


RESULTS
Enolase protein was detected at every stage in parasite life cycle examined. In asexual stages, enolase was predominantly (>or=85-90%) present in soluble fraction, while in sexual stages it was mostly associated with particulate fraction. Apart from cytosol, enolase was found to be associated with nucleus, food vacuole, cytoskeleton and plasma membrane.


CONCLUSIONS
Diverse localization of enolase suggests that apart from catalyzing the conversion of 2-phosphoglycericacid into phosphoenolpyruvate in glycolysis, enolase may be involved in a host of other biological functions. For instance, enolase localized on the merozoite surface may be involved in red blood cell invasion; vacuolar enolase may be involved in food vacuole formation and/or development; nuclear enolase may play a role in transcription.
Bhowmick
Ipsita Pal
IP
Department of Biological Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai-400005, India. ipsitapb@gmail.com
Kumar
Nirbhay
N
Sharma
Shobhona
S
Coppens
Isabelle
I
Jarori
Gotam K
GK
D000818:Animals; D015153:Blotting, Western; D002458:Cell Fractionation; D002467:Cell Nucleus / Q000737:chemistry; D003600:Cytosol / Q000737:chemistry; D051379:Mice; D008856:Microscopy, Fluorescence; D016253:Microscopy, Immunoelectron; D010751:Phosphopyruvate Hydratase / Q000032:analysis*; D010963:Plasmodium falciparum / Q000737:chemistry*; D014617:Vacuoles / Q000737:chemistry
D010751:Phosphopyruvate Hydratase