期刊
出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.cbpb.2020.110511
关键词
Cathepsin D; Urease; Triatomine; Mechanism of action; Toxicity
资金
- SECyT-UNC (CONSOLIDAR 2018-21)
- FONCyT [PICT 2016-1351]
- CONICET [PIP 0159]
- Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) [47.5908/2012, 446052/2014-1]
- Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) [001, 63/2010, 1205/2011, PVE 054/2012]
- Fundacao de Amparo a Pesquisa do Estado do Rio Grande do Sul (FAPERGS) [10/0014-2]
In this study, the effects of JBU on DmCatD activity in the hematophagous insect Dipetalogaster maxima were investigated. JBU injections resulted in a significant increase of DmCatD activity, particularly in the posterior midgut. These changes were tissue-specific and not correlated with modifications in DmCatD mRNA and protein levels, suggesting a direct effect of the toxin on DmCatD activity.
In insects, cathepsin D is a lysosomal aspartic endopeptidase involved in several functions such as digestion, defense and reproduction. Jack Bean Urease (JBU) is the most abundant urease isoform obtained from the seeds of the plant Canavalia ensiformis. JBU is a multifunctional protein with entomotoxic effects unrelated to its catalytic activity, by mechanisms not yet fully understood. In this work, we employed nymphs of the hematophagous insect Dipetalogaster maxima as an experimental model in order to study the effects of JBU on D. maxima CatD (DmCatD). In insects without treatment, immunofluorescence assays revealed a conspicuous distribution pattern of DmCatD in the anterior and posterior midgut as well as in the fat body and hemocytes. Western blot assays showed that the active form of DmCatD was present in the fat body, the anterior and posterior midgut; whereas the proenzyme was visualized in hemocytes and hemolymph. The transcript of DmCatD and its enzymatic activity was detected in the anterior and posterior midgut as well as in fat body and hemocytes. JBU injections induced a significant increase of DmCatD activity in the posterior midgut (at 3 h post-injection) whereas in the hemolymph, such an effect was observed after 18 h. These changes were not correlated with modifications in DmCatD mRNA and protein levels or changes in the immunofluorescence pattern. In vitro experiments might suggest a direct effect of the toxin in DmCatD activity. Our findings indicated that the tissue-specific increment of cathepsin D activity is a novel effect of JBU in insects.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据