A novel C-type lectin with triple carbohydrate recognition domains has critical roles for the hard tick Haemaphysalis longicornis against Gram-negative bacteria

Hiroki Maeda; Takeshi Miyata; Kodai Kusakisako; Remil Linggatong Galay; Melbourne Rio Talactac; Rika Umemiya-Shirafuji; Masami Mochizuki; Kozo Fujisaki; Tetsuya Tanaka

doi:10.1016/j.dci.2015.12.015

A novel C-type lectin with triple carbohydrate recognition domains has critical roles for the hard tick Haemaphysalis longicornis against Gram-negative bacteria

Dev Comp Immunol. 2016 Apr:57:38-47. doi: 10.1016/j.dci.2015.12.015. Epub 2015 Dec 25.

Authors

Hiroki Maeda¹, Takeshi Miyata², Kodai Kusakisako¹, Remil Linggatong Galay³, Melbourne Rio Talactac¹, Rika Umemiya-Shirafuji⁴, Masami Mochizuki¹, Kozo Fujisaki⁵, Tetsuya Tanaka⁶

Affiliations

¹ Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Korimoto, Kagoshima 890-0065, Japan; Department of Pathological and Preventive Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida, Yamaguchi 753-8515, Japan.
² Division of Molecular Functions of Food, Department of Biochemistry and Biotechnology, Kagoshima University, Korimoto, Kagoshima 890-0065, Japan.
³ Department of Veterinary Paraclinical Sciences, College of Veterinary Medicine, University of the Philippines Los Baños, Los Baños, Laguna 4031, Philippines.
⁴ National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, Hokkaido 080-8555, Japan.
⁵ Zen-noh Institute of Animal Health, Ooja, Sakura, Chiba 285-0043, Japan.
⁶ Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Korimoto, Kagoshima 890-0065, Japan; Department of Pathological and Preventive Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida, Yamaguchi 753-8515, Japan. Electronic address: tetsuya@ms.kagoshima-u.ac.jp.

PMID: 26724379
DOI: 10.1016/j.dci.2015.12.015

Abstract

C-type lectins (CLecs) play an important role in innate immunity against invaders. In this study, a novel CLec was identified from Haemaphysalis longicornis ticks (HlCLec). HlCLec contains a signal peptide and a transmembrane region. Interestingly, HlCLec possesses three dissimilar carbohydrate recognition domains (CRDs). Each CRD contains the mutated motif of Ca(2+)-binding site 2. HlCLec mRNA was up-regulated during blood feeding, and had highest expression in the midgut and ovary. HlCLec localization was also confirmed by immunofluorescent antibody test (IFAT). HlCLec was found on the cell membrane and basal lamina of midgut and ovary. In addition, the recombinant HlCLec and individual CRDs demonstrated direct binding activity to Escherichia coli and Staphylococcus aureus; however, no growth inhibition activity was observed. Furthermore, E. coli injection after silencing of HlCLec caused drastic reduction in survival rate of ticks. These results strongly suggest the key role of HlCLec in tick innate immunity against Gram-negative bacteria.

Keywords: C-type lectin; Gram-negative bacteria; Innate immunity; Recombinant; Tick.

MeSH terms

Amino Acid Sequence
Animals
Carbohydrates / immunology
Cloning, Molecular
Escherichia coli / growth & development*
Gram-Negative Bacterial Infections / immunology*
Immunity, Innate / genetics
Ixodidae / immunology*
Lectins, C-Type / genetics
Lectins, C-Type / metabolism*
Molecular Sequence Data
Protein Binding
RNA, Small Interfering / genetics
Receptors, Pattern Recognition / genetics
Receptors, Pattern Recognition / metabolism*
Staphylococcus aureus / growth & development*
Transgenes / genetics

Substances

Carbohydrates
Lectins, C-Type
RNA, Small Interfering
Receptors, Pattern Recognition