Rmcystatin3, a cysteine protease inhibitor from Rhipicephalus microplus hemocytes involved in immune response

Autor(es)

Lu, Stephen ^[1] ; Soares, Tatiane S. ^[1] ; Vaz Junior, Itabajara S. ^[2] ; Lovato, Diogo V. ^[1] ; Tanaka, Aparecida S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Dept Biochem, Escola Paulista Med, BR-04044020 Sao Paulo - Brazil

^[2] Univ Fed Rio Grande do Sul, Ctr Biotecnol Estado Rio Grande do Sul, Porto Alegre, RS - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Biochimie; v. 106, p. 17-23, NOV 2014.
• Citações Web of Science: 7

Resumo

The Rhipicephalus microplus tick is responsible for losses in the livestock production estimated in 2 billions USD. Despite its economical importance the knowledge in tick's physiology is sparse. In order to contribute to this scenario we describe the characterization of a cysteine proteinase inhibitor named Rmcystatin-3. Purified recombinant Rmcystatin-3 was able to inhibit cathepsin L (Ki = 2.5 nM), BmCl1 (Ki = 1.8 nM) and cathepsin B (Ki = 136 nM). Western blot and quantitative PCR analysis revealed the presence of Rmcystatin-3 in fat body, salivary gland but mainly in hemocytes. The mRNA levels of Rmcystatin-3 during bacterial challenge are drastically down-regulated. In order to define the Rmcystatin-3 possible role in tick immunity, the cystatin gene was knockdown by RNA interference with and without Escherichia coil infection. Our results showed that the Rmcystatin-3 silenced group was more immune competent to control bacterial infection than the group injected with non-related dsRNA. Taking together, our data strongly suggested an important role of Rmcystatin-3 in tick immunity. (C) 2014 Elsevier B.V. and Societe francaise de biochimie et biologie Moleculaire (SFBBM). All rights reserved. (AU)

• Processo FAPESP: 05/03514-9 - Estudos da função fisiológica e potencial biotecnológico de inibidores de proteases e anti-hemostáticos presentes em artrópodes hematófagos
• Beneficiário: Aparecida Sadae Tanaka
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 12/03657-8 - Inibidores e proteases de ectoparasitas: relação de estrutura-função e identificação do papel dessas moléculas na interação de vetores de doenças e seus agentes etiológicos
• Beneficiário: Aparecida Sadae Tanaka
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 09/17589-1 - Purificação e caracterização do inibidor de cisteinoproteases Bmcistatina-2 presente em hemócitos de carrapato Rhipicephalus (Boophilus) microplus.
• Beneficiário: Stephen Lu
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica