PERSONAL DE APOYO
DIAZ AÑEL Alberto Marcelo
artículos
Título:
Stimulation of Trypanosoma cruzi adenylyl cyclase by an alphaD-globin fragment from Triatoma hindgut: Effect on differentiation of epimastigote to trypomastigote forms
Autor/es:
FRAIDENRAICH, D.; PEÑA,; ISOLA,; LAMMEL,; COSO, O.; DIAZ AÑEL, A. M.; PONGOR,; BARALLE,; TORRES, H.; FLAWIA, M.
Revista:
Proceedings of the National Academy of Sciences of the United States of America
Editorial:
National Academy of Sciences
Referencias:
Año: 1993 vol. 90 p. 10140 - 10144
ISSN:
0027-8424
Resumen:
A peptide from hindguts of the Triatoma hematophagous Chagas insect
vector activates adenylyl cyclase activity in Trypanosoma cruzi
epimastigote membranes and stimulates the in vitro differentiation of
epimastigotes to metacyclic trypomastigotes. Hindguts were obtained
from insects fed 2 days earlier with chicken blood. Purification was
performed by gel filtration and HPLC on C18 and C4 columns. SDS/PAGE of
the purified peptide showed a single band of about 10 kDa. The
following sequence was determined for the 20 amino-terminal residues of
this peptide: H2N-Met-Leu-Thr-Ala-Glu-Asp-Lys-Lys-Leu-Ile-Gln-
Gln-Ala-Trp-Glu-Lys-Ala-Ala-Ser-His. This sequence is identical to the
amino terminus of chicken alpha D-globin. On a Western blot, the
peptide immunoreacted with a polyclonal antibody against chicken globin
D. A synthetic peptide corresponding to residues 1-40 of the alpha
D-globin amino terminus also stimulated adenylyl cyclase activity and
promoted differentiation. This 125I-labeled synthetic peptide bound
specifically to T. cruzi epimastigote cells. Activation of epimastigote
adenylyl cyclase by the hemoglobin-derived peptide may play an
important role in T. cruzi differentiation and consequently in the
transmission of Chagas disease.