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A novel form of actin in Leishmania: molecular characterisation,subcellular localisation and association with subpellicular microtubules

IR@CDRI: CSIR-Central Drug Research Institute, Lucknow

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Field Value
 
Creator Sahasrabuddhe, Amogh A
Bajpai, V K
Gupta, C M
 
Date 2008-10-23T20:54:15Z
2008-10-23T20:54:15Z
2004
 
Identifier Mol.Biochem.Parasitol.134,105-114(105-114)
http://hdl.handle.net/123456789/204
 
Description To study the occurrence and subcellular distribution of actin in trypanosomatid parasites, we have cloned and overexpressed Leishmania donovani actin gene in bacteria, purified the protein, and employed the affinity purified rabbit polyclonal anti-recombinant actin antibodies as a probe to study the organisation and subcellular distribution of actin in Leishmania cells. The Leishmania actin did not cross react with antimammalianactin antibodiesbut was readilyrecognizedby the anti-Leishmaniaactin antibodiesin both the promastigote and amastigote forms of the parasite. About 106copies per cell of this protein (Mr 42.05 kDa) were present in the Leishmania promastigote.Unlike other eukaryotic actins, the oligomeric forms of Leishmania actin were not stained by phalloidin nor were dissociated by actin filament-disrupting agents, like Latrunculin Band Cytochalasin D. Analysis of the primary structure of this protein revealed that these unusual characteristics may be related to the presence of highly diverged amino acids in the DNase I-binding loop (amino acids 40-50)and the hydrophobic plug (amino acids 262-272) regions of Leishmania actin. The subcellular distribution of actin was studied in the Leishmania promastigotes by employing immunoelectron and immunofluorescence microscopies. This protein was present not only in the flagella, flagellar pocket. nucleus and the kinetoplast but it was also localized on the nuclear, vacuolar and cytoplasmic face of the plasma membranes. Further, the plasma membrane-associated actin was colocalised with subpellicular microtubules, while most of the actin present in the kinetoplast colocalised with the k-DNA network. These results clearly indicate that Leishmania contains a novel form of actin which may structurally and functionally differ from other eukaryotic actins. The functional significance of these observations is discussed.
 
Format 5225975 bytes
application/pdf
 
Language en
 
Relation CDRI.Communication no 6366
 
Subject Trypanosomatids
Actin
Microtubules
k-DNA network
Association
Cellular functions
 
Title A novel form of actin in Leishmania: molecular characterisation,subcellular localisation and association with subpellicular microtubules
 
Type Article