Genome-wide analysis reveals increased levels of transcripts related with infectivity in peanut lectin non-agglutinated promastigotes of Leishmania infantum.
Metacyclic promastigotes are transmitted during bloodmeals after development inside the gut of the sandfly vector. The isolation from axenic cultures of procyclic and metacyclic promastigotes by peanut lectin agglutination followed by differential centrifugation is controversial in Leishmania infantum. The purpose of this study has been to isolate both fractions simultaneously from the same population in stationary phase of axenic culture and compare their expression profiles by whole-genome shotgun DNA microarrays. The 317 genes found with meaningful values of stage-specific regulation demonstrate that negative selection of metacyclic promastigotes by PNA agglutination is feasible in L. infantum and both fractions can be isolated. This subpopulation up-regulates a cysteine peptidase A and several genes involved in lipophosphoglycan, proteophosphoglycan and glycoprotein biosynthesis, all related with infectivity. In fact, we have confirmed the increased infection rate of PNA(-) promastigotes by U937 human cell line infection experiments. These data support that metacyclic promastigotes are related with infectivity and the lack of agglutination with PNA is a phenotypic marker for this subpopulation.
Departamento de Ciencia de Proteínas and Departamento de Microbiología Molecular, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), Calle Ramiro de Maeztu 9, 28040 Madrid, Spain.
Pedro J
PJ
Alcolea
Ana
A
Alonso
Alicia
A
Sánchez-Gorostiaga
Mercedes
M
Moreno-Paz
Manuel J
MJ
Gómez
Irene
I
Ramos
Víctor
V
Parro
Vicente
V
Larraga
D000371:Agglutination; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D003546:Cysteine Endopeptidases / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000235:genetics*; D018503:Genome, Protozoan / Q000235:genetics*; D006801:Humans; D018314:Leishmania infantum / Q000235:genetics* / Q000472:pathogenicity; D008018:Life Cycle Stages / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D019887:Peanut Agglutinin / Q000378:metabolism; D014774:Virulence
D000596:Amino Acids; D005227:Fatty Acids; D019887:Peanut Agglutinin; D003546:Cysteine Endopeptidases