Molecular and structural characterization of novel cystatins from the taiga tick Ixodes persulcatus

Publication date: Available online 31 January 2017 Source:Ticks and Tick-borne Diseases Author(s): Carolina K. Rangel, Luís F. Parizi, Gabriela A. Sabadin, Evenilton P. Costa, Nelilma C. Romeiro, Masayoshi Isezaki, Naftaly W. Githaka, Adriana Seixas, Carlos Logullo, Satoru Konnai, Kazuhiko Ohashi, Itabajara da Silva Vaz Cystatins are cysteine peptidase inhibitors that in ticks mediate processes such as blood feeding and digestion. The ixodid tick Ixodes persulcatus is endemic to the Eurasia, where it is the principal vector of Lyme borreliosis. To date, no I. persulcatus cystatin has been characterized. In the present work, we describe three novel cystatins from I. persulcatus, named JpIpcys2a, JpIpcys2b and JpIpcys2c. In addition, the potential of tick cystatins as cross-protective antigens was evaluated by vaccination of hamsters using BrBmcys2c, a cystatin from Rhipicephalus microplus, against I. persulcatus infestation. Sequence analysis showed that motifs that are characteristic of cystatins type 2 are fully conserved in JpIpcys2b, while mutations are present in both JpIpcys2a and JpIpcys2c. Protein-protein docking simulations further revealed that JpIpcys2a, JpIpcys2b and JpIpcys2c showed conserved binding sites to human cathepsins L, all of them covering the active site cleft. Cystatin transcripts were detected in different I. persulcatus tissues and instars, showing their ubiquitous expression during I. persulcatus development. Serological analysis show...
Source: Ticks and Tick borne Diseases - Category: Zoology Source Type: research