Characterization and function analysis of a novel gene, Hc-maoc-1, in the parasitic nematode Haemonochus contortus.
Enoyl-CoA hydratase (MAOC) is required for the biosynthesis of the fatty acid-derive side chains of the ascaroside via peroxisome β-oxidation in the free-living nematode Caenorhabditis elegans. The derivative of dideoxy-sugar, ascarylose is used as dauer pheromones or daumones to induce development of the stress-resistant dauer larvae stage.



Hc-maoc-1 gene was obtained by searching the Wellcome Trusts Sanger Institute's H. contortus genomic database. qRT-PCR was performed to analyse the transcriptional levels of Hc-maoc-1 with different developmental stages as templates. IFA was carried out to determine the expression pattern in L3 larvae and micro-injection was used to verify the promoter activity of 5'-flanking region of Hc-maoc-1. Overexpression and RNAi experiments were applied in N2strain to ascertain the gene function of Hc-maoc-1.



The full-length cDNA of Hc-maoc-1 was 900 bp in length, which contained eight exons separated by seven introns and possessed the Hotdog domain and the MaoC-like domain, together with several other residues and a hydratase 2 motif. It was transcribed throughout the lifecycle and peaked in the fourth-stage larvae (L4) of H. contortus; however, its transcription level decreased in diapausing L4. The protein expression and location of Hc-MAOC-1 were mainly in the intestine of L3 larvae. Overexpression of Ce-maoc-1 and Hc-maoc-1 in C. elegans showed extended lifespan and increased body size. The protein Ce-MAOC-1 and Hc-MAOC-1 were localized in the intestine with a punctate pattern. In C. elegans, knockdown of Ce-maoc-1 conferred shortened lifespan and body lengths, decreased brood size and increased lipid storage.



Caenorhabditis elegans was used as a model organism to ascertain the function of Hc-maoc-1 in H. contortus. Our results showed the similar characteristics and functions with Ce-maoc-1 and provided evidences of the potential functions of Hc-maoc-1 in biosynthesis of daumones in H. contortus.
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China.
Haojie
H
Ding
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China.
Hengzhi
H
Shi
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China.
Yu
Y
Shi
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China.
Xiaolu
X
Guo
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China.
Xiuping
X
Zheng
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China.
Xueqiu
X
Chen
Faculty of Life Science and Biotechnology, Ningbo University, Ningbo, 315211, China.
Qianjin
Q
Zhou
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China. yangyi0607@zju.edu.cn.
Yi
Y
Yang
College of Animal Sciences, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, 310058, China. afdu@zju.edu.cn.
Aifang
A
Du
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000254:growth & development; D004746:Enoyl-CoA Hydratase / Q000235:genetics* / Q000378:metabolism*; D019085:Fluorescent Antibody Technique, Direct; D020869:Gene Expression Profiling; D006189:Haemonchus / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
D004746:Enoyl-CoA Hydratase
Caenorhabditis elegans; Ce-maoc-1; Diapause; Haemonchus contortus; Hc-maoc-1