title: A Nematode Calreticulin, Rs-CRT, Is a Key Effector in Reproduction and Pathogenicity of Radopholus similis.
abstract: Radopholus similis is a migratory plant-parasitic nematode that causes severe damage to many agricultural and horticultural crops. Calreticulin (CRT) is a Ca2+-binding multifunctional protein that plays key roles in the parasitism, immune evasion, reproduction and pathogenesis of many animal parasites and plant nematodes. Therefore, CRT is a promising target for controlling R. similis. In this study, we obtained the full-length sequence of the CRT gene from R. similis (Rs-crt), which is 1,527-bp long and includes a 1,206-bp ORF that encodes 401 amino acids. Rs-CRT and Mi-CRT from Meloidogyne incognita showed the highest similarity and were grouped on the same branch of the phylogenetic tree. Rs-crt is a multi-copy gene that is expressed in the oesophageal glands and gonads of females, the gonads of males, the intestines of juveniles and the eggs of R. similis. The highest Rs-crt expression was detected in females, followed by juveniles, eggs and males. The reproductive capability and pathogenicity of R. similis were significantly reduced after treatment with Rs-crt dsRNA for 36 h. Using plant-mediated RNAi, we confirmed that Rs-crt expression was significantly inhibited in the nematodes, and resistance to R. similis was significantly improved in transgenic tomato plants. Plant-mediated RNAi-induced silencing of Rs-crt could be effectively transmitted to the F2 generation of R. similis; however, the silencing effect of Rs-crt induced by in vitro RNAi was no longer detectable in F1 and F2 nematodes. Thus, Rs-crt is essential for the reproduction and pathogenicity of R. similis.
authors.affiliation: Laboratory of Plant Nematology and Research Center of Nematodes of Plant Quarantine, Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.affiliation: Laboratory of Plant Nematology and Research Center of Nematodes of Plant Quarantine, Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Wang
authors.affiliation: Laboratory of Plant Nematology and Research Center of Nematodes of Plant Quarantine, Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Xie
authors.affiliation: Laboratory of Plant Nematology and Research Center of Nematodes of Plant Quarantine, Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, 510642, China; Paulownia Research and Development Center of State Forestry Administration, Zhengzhou, Henan, 450003, China.
authors.forename: Yan-Tao
authors.initials: YT
authors.lastname: Wang
authors.affiliation: Laboratory of Plant Nematology and Research Center of Nematodes of Plant Quarantine, Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
authors.forename: Dong-Wei
authors.initials: DW
authors.lastname: Wang
authors.affiliation: Laboratory of Plant Nematology and Research Center of Nematodes of Plant Quarantine, Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
authors.forename: Chun-Lin
authors.initials: CL
authors.lastname: Xu
authors.affiliation: Laboratory of Plant Nematology and Research Center of Nematodes of Plant Quarantine, Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Department of Entomology, Rutgers University, New Brunswick, New Jersey, 08901, United States of America.
authors.forename: De-Sen
authors.initials: DS
authors.lastname: Wang
mesh_terms: D000818:Animals; D037282:Calreticulin / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D005260:Female; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development / Q000469:parasitology; D008297:Male; D010802:Phylogeny; D010935:Plant Diseases / Q000469:parasitology*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D017385:Sequence Homology; D014431:Tylenchoidea / Q000472:pathogenicity* / Q000502:physiology
chemical_list: D037282:Calreticulin; D015800:Protozoan Proteins