DmCatD, a cathepsin D-like peptidase of the hematophagous insect Dipetalogaster maxima (Hemiptera: Reduviidae): Purification, bioinformatic analyses and the significance of its interaction with lipophorin in the internalization by developing oocytes.

Autor: Leyria J; Departamento de Bioquímica Clínica-CIBICI-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina. Electronic address: jleyria@fcq.unc.edu.ar., Fruttero LL; Departamento de Bioquímica Clínica-CIBICI-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina; Brain Institute (Instituto do Cérebro-INSCER), Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil. Electronic address: lfruttero@fcq.unc.edu.ar., Ligabue-Braun R; Center of Biotechnology, Universidade Federal do Rio Grande do Sul Porto Alegre, RS, Brazil. Electronic address: rodrigobraun@cbiot.ufrgs.br., Defferrari MS; Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada. Electronic address: marina.defferrari@utoronto.ca., Arrese EL; Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA. Electronic address: destela@okstate.edu., Soulages JL; Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA. Electronic address: jose.soulages@okstate.edu., Settembrini BP; Museo Argentino de Ciencias Naturales, Ciudad Autónoma de Buenos Aires, Argentina. Electronic address: settembrini@macn.gov.ar., Carlini CR; Brain Institute (Instituto do Cérebro-INSCER), Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil; Center of Biotechnology, Universidade Federal do Rio Grande do Sul Porto Alegre, RS, Brazil. Electronic address: celia.carlini@pucrs.br., Canavoso LE; Departamento de Bioquímica Clínica-CIBICI-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina. Electronic address: lcanavo@fcq.unc.edu.ar.
Jazyk: angličtina
Zdroj: Journal of insect physiology [J Insect Physiol] 2018 Feb - Mar; Vol. 105, pp. 28-39. Date of Electronic Publication: 2018 Jan 08.
DOI: 10.1016/j.jinsphys.2018.01.002
Abstrakt: DmCatD, a cathepsin D-like peptidase of the hematophagous insect Dipetalogaster maxima, is synthesized by the fat body and the ovary and functions as yolk protein precursor. Functionally, DmCatD is involved in vitellin proteolysis. In this work, we purified and sequenced DmCatD, performed bioinformatic analyses and investigated the events involved in its targeting and storage in developing oocytes. By ion exchange and gel filtration chromatography, DmCatD was purified from egg homogenates and its identity was confirmed by mass spectrometry. Approximately 73% of the full-length transcript was sequenced. The phylogeny indicated that DmCatD has features which suggest its distancing from "classical" cathepsins D. Bioinformatic analyses using a chimeric construct were employed to predict post-translational modifications. Structural modeling showed that DmCatD exhibited the expected folding for this type of enzyme, and an active site with conserved architecture. The interaction between DmCatD and lipophorin in the hemolymph was demonstrated by co-immunoprecipitation. Colocalization of both proteins in developing oocyte membranes and yolk bodies was detected by immunofluorescence. Docking assays favoring the interaction DmCatD-lipophorin were carried out after modeling lipophorin of a related triatomine species. Our results suggest that lipophorin acts as a carrier for DmCatD to facilitate its further internalization by the oocytes. The mechanisms involved in the uptake of peptidases within the oocytes of insects have not been reported. This is the first experimental work supporting the interaction between cathepsin D and lipophorin in an insect species, enabling us to propose a pathway for its targeting and storage in developing oocytes.
(Copyright © 2018 Elsevier Ltd. All rights reserved.)
Databáze: MEDLINE
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