Studies on the CPA cysteine peptidase in the Leishmania infantum genome strain JPCM5

Autor: Graham H. Coombs, Audrey Ambit, Maribel Jiménez, Arno N Vermeulen, Jeremy C. Mottram, Jacqueline Poot, Daland C Herrmann, Hubert Denise
Rok vydání: 2006
Předmět:
lcsh:QH426-470
030231 tropical medicine
Leishmania mexicana
Molecular Sequence Data
Protozoan Proteins
Virulence
medicine.disease_cause
Genome
Gene Expression Regulation
Enzymologic
03 medical and health sciences
0302 clinical medicine
Dogs
Cricetinae
parasitic diseases
medicine
Parasite hosting
Animals
Humans
Amino Acid Sequence
lcsh:QH573-671
Leishmania infantum
Molecular Biology
030304 developmental biology
QR355
Genetics
0303 health sciences
Mutation
biology
Mesocricetus
Sequence Homology
Amino Acid
lcsh:Cytology
Reverse Transcriptase Polymerase Chain Reaction
Leishmaniasis
U937 Cells
biology.organism_classification
medicine.disease
Blotting
Northern
3. Good health
lcsh:Genetics
Blotting
Southern
Cysteine Endopeptidases
Visceral leishmaniasis
Leishmaniasis
Visceral
Genome
Protozoan
Gene Deletion
Research Article
Zdroj: BMC Molecular Biology
Repisalud
Instituto de Salud Carlos III (ISCIII)
BMC Molecular Biology, Vol 7, Iss 1, p 42 (2006)
ISSN: 1471-2199
Popis: BackgroundVisceral leishmaniasis caused by members of theLeishmania donovanicomplex is often fatal in the absence of treatment. Research has been hampered by the lack of good laboratory models and tools for genetic manipulation. In this study, we have characterised aL. infantumline (JPCM5) that was isolated from a naturally infected dog and then cloned. We found that JPCM5 has attributes that make it an excellent laboratory model; different stages of the parasite life cycle can be studiedin vitro, it is accessible to genetic manipulation and it has retained its virulence. Furthermore, theL. infantumJPCM5 genome has now been fully sequenced.ResultsWe have further focused our studies onLiCPA, theL. infantumhomologue toL. mexicanacysteine peptidase CPA. LiCPA was found to share a high percentage of amino acid identity with CPA proteins of otherLeishmaniaspecies. Two independentLiCPA-deficient promastigote clones (ΔLicpa) were generated and their phenotype characterised. In contrast toL. mexicana CPA-deficient mutants, both clones of ΔLicpawere found to have significantly reduced virulencein vitroandin vivo. Re-expression of just oneLiCPAallele (giving ΔLicpa::CPA) was sufficient to complement the reduced infectivity of both ΔLicpamutants for human macrophages, which confirms the importance of LiCPA forL. infantumvirulence. In contrast,in vivoexperiments did not show any virulence recovery of the re-expressor clone ΔLicpaC1::CPA compared with the CPA-deficient mutant ΔLicpaC1.ConclusionThe data suggest that CPA is not essential for replication ofL. infantumpromastigotes, but is important for the host-parasite interaction. Further studies will be necessary to elucidate the precise roles that LiCPA plays and why the re-expression of LiCPA in the ΔLicpamutants complemented the gene deletion phenotype only inin vitroand not inin vivoinfection of hamsters.
Databáze: OpenAIRE
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