A protein phosphatase 1 gamma (PP1γ) of the human protozoan parasite Trichomonas vaginalis is involved in proliferation and cell attachment to the host cell.
In this work, evidence for a critical role of Trichomonas vaginalis protein phosphatase 1 gamma (TvPP1γ) in proliferation and attachment of the parasite to the mammalian cell is provided. Firstly, proliferation and attachment of T. vaginalis parasites to HeLa cells was blocked by calyculin A (CA), a potent PP1 inhibitor. Secondly, it was demonstrated that the enzyme activity of native and recombinant TvPP1γ proteins was inhibited by CA. Thirdly, reverse genetic studies confirmed that antisense oligonucleotides targeted to PP1γ but not PP1α or β inhibited proliferation and attachment of trichomonads CA-treated parasites underwent cytoskeletal modifications, including a lack of axostyle typical labelling, suggesting that cytoskeletal phosphorylation could be regulated by a CA-sensitive phosphatase where the role of PP1γ could not be ruled out. Analysis of subcellular distribution of TvPP1γ by cell fractionation and electron microscopy demonstrated the association between TvPP1γ and the cytoskeleton. The expression of adhesins, AP120 and AP65, at the cell surface was also inhibited by CA. The concomitant inhibition of expression of adhesins and changes in the cytoskeleton in CA-treated parasites suggest a specific role for PP1γ -dependent dephosphorylation in the early stages of the host-parasite interaction. Molecular modelling of TvPP1γ showed the conservation of residues critical for maintaining proper folding into the gross structure common to PP1 proteins. Taken together, these results suggest that TvPP1γ could be considered a potential novel drug target for treatment of trichomoniasis.
Department of Medical Technology, University of Antofagasta, Antofagasta, P.O. Box 170, Chile.
Christian
C
Muñoz
Mauricio
M
Pérez
Patricio R
PR
Orrego
Luis
L
Osorio
Bessy
B
Gutiérrez
Hernán
H
Sagua
Juan L
JL
Castillo
Jose
J
Martínez-Oyanedel
Rossana
R
Arroyo
Patricia
P
Meza-Cervantez
Jose Franco
JF
da Silveira
Victor
V
Midlej
Marlene
M
Benchimol
Esteban
E
Cordero
Patricio
P
Morales
Jorge E
JE
Araya
Jorge
J
González
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D002448:Cell Adhesion; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000469:parasitology; D005260:Female; D006367:HeLa Cells; D006790:Host-Parasite Interactions; D006801:Humans; D008969:Molecular Sequence Data; D054645:Protein Phosphatase 1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D014247:Trichomonas Vaginitis / Q000469:parasitology*; D014246:Trichomonas vaginalis / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000502:physiology
D015800:Protozoan Proteins; D054645:Protein Phosphatase 1