TY - JOUR
T1 - Functions of Armigeres subalbatus C-type lectins in innate immunity
AU - Shi, Xiu Zhen
AU - Kang, Cui Jie
AU - Wang, Song Jie
AU - Zhong, Xue
AU - Beerntsen, Brenda T.
AU - Yu, Xiao Qiang
N1 - Funding Information:
This work was supported by National Institutes of Health Grant AI082253 and a grant ( FEB12 ) from the University of Missouri Research Board (UMRB) .
PY - 2014/9
Y1 - 2014/9
N2 - C-type lectins (CTLs) are a superfamily of calcium-dependent carbohydrate binding proteins containing at least one carbohydrate-recognition domain (CRD) and they are present in almost all metazoans. Insect CTLs may function as pattern-recognition receptors and play important roles in innate immunity. In this study, we selected five AsCTLs from the mosquito Armigeres subalbatus, a natural vector of filarial nematodes, and performed both invitro and invivo studies to elucidate their functions in innate immunity. AsCTLMA15, AsCTLGA5 and AsCTL15 were mainly expressed in hemocytes, AsCTL16 was expressed in fat body, while AsCTLMA11 was expressed in both hemocytes and fat body, and only AsCTLMA11 and AsCTL16 were expressed at high levels in adult females. Invitro binding assays showed that all five recombinant AsCTLs could bind to different microbial cell wall components, including lipopolysaccharide (LPS), lipid A, peptidoglycan (PG), lipoteichoic acid (LTA), zymosan and laminarin (beta-1,3-glucan). Recombinant AsCTLs also bound to several Gram-negative and Gram-positive bacteria, and could agglutinate bacterial cells. Injection of double-stranded RNAs (dsRNAs) could significantly reduce expression of the five As CTL mRNAs, and the survival of mosquitoes treated with dsRNA to AsCTLGA5 was significantly decreased after Escherichia coli infection, but did not change significantly after Micrococcus luteus infection compared to the control groups, suggesting that Ar. subalbatus AsCTLGA5 may participate in innate immunity against E.coli.
AB - C-type lectins (CTLs) are a superfamily of calcium-dependent carbohydrate binding proteins containing at least one carbohydrate-recognition domain (CRD) and they are present in almost all metazoans. Insect CTLs may function as pattern-recognition receptors and play important roles in innate immunity. In this study, we selected five AsCTLs from the mosquito Armigeres subalbatus, a natural vector of filarial nematodes, and performed both invitro and invivo studies to elucidate their functions in innate immunity. AsCTLMA15, AsCTLGA5 and AsCTL15 were mainly expressed in hemocytes, AsCTL16 was expressed in fat body, while AsCTLMA11 was expressed in both hemocytes and fat body, and only AsCTLMA11 and AsCTL16 were expressed at high levels in adult females. Invitro binding assays showed that all five recombinant AsCTLs could bind to different microbial cell wall components, including lipopolysaccharide (LPS), lipid A, peptidoglycan (PG), lipoteichoic acid (LTA), zymosan and laminarin (beta-1,3-glucan). Recombinant AsCTLs also bound to several Gram-negative and Gram-positive bacteria, and could agglutinate bacterial cells. Injection of double-stranded RNAs (dsRNAs) could significantly reduce expression of the five As CTL mRNAs, and the survival of mosquitoes treated with dsRNA to AsCTLGA5 was significantly decreased after Escherichia coli infection, but did not change significantly after Micrococcus luteus infection compared to the control groups, suggesting that Ar. subalbatus AsCTLGA5 may participate in innate immunity against E.coli.
KW - Armigeres subalbatus
KW - C-type lectin
KW - Innate immunity
KW - RNAi
KW - Survival
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U2 - 10.1016/j.ibmb.2014.06.010
DO - 10.1016/j.ibmb.2014.06.010
M3 - Article
C2 - 25014898
AN - SCOPUS:84904757378
SN - 0965-1748
VL - 52
SP - 102
EP - 114
JO - Insect Biochemistry and Molecular Biology
JF - Insect Biochemistry and Molecular Biology
IS - 1
ER -