title: Molecular cloning, characterization and expression analysis of two juvenile hormone esterase-like carboxylesterase cDNAs in Chinese mitten crab, Eriocheir sinensis.
abstract: Precise regulation of methyl farnesoate (MF) titer is of prime importance throughout the crustacean life-cycle. Although the synthetic pathway of MF is well-documented, little is known about its degradation and recycling in crustaceans. Juvenile hormone esterase-like (JHE-like) carboxylesterase (CXE) is a key enzyme in MF degradation, thus playing a significant role in regulating the MF titer. We identified and characterized two cDNAs, Es-CXE1 and Es-CXE2, encoding JHE-like CXEs in Chinese mitten crab. Full-length cDNAs of Es-CXE1 and Es-CXE2 encode proteins composed of 584 and 597 amino acids, respectively, both of which contain a typical carboxylesterase domain. Alignment and phylogenetic analyses revealed that the Es-CXEs are highly similar to those of other crustaceans. To further validate their functions, we evaluated the mRNA expression patterns of the Es-CXEs in various tissues and in different physiological conditions. Tissue-specific expression analysis showed that the two Es-CXEs were predominantly expressed in the hepatopancreas and ovaries, which are the major tissues for MF metabolism. Es-CXE2 expression levels in the hepatopancreas and ovaries were about 100 and 25-fold higher, than the respective Es-CXE1 expressions. During ovarian rapid development stage, the global expressions of Es-CXEs were up-regulated in the hepatopancreas and down-regulated in the ovaries. After eyestalk ablation (ESA), the mRNA expressions of the two Es-CXEs were up-regulated in the hepatopancreas, further indicating their potential in degrading MF. Taken together, our results suggest that Es-CXEs, the key component of the juvenile hormone degradation pathway, may play vital roles in the development and reproduction of the Chinese mitten crab.
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China.
authors.forename: Muzi
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China.
authors.forename: Yanfei
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China.
authors.forename: Yuanjie
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China.
authors.forename: Xuguang
authors.initials: X
authors.lastname: Li
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China.
authors.forename: Quanping
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China; The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Nanjing 210014, China.
authors.forename: Jiachun
authors.initials: J
authors.lastname: Ge
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China; The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Nanjing 210014, China.
authors.forename: Jianlin
authors.initials: J
authors.lastname: Pan
authors.affiliation: Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China; The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Germplasm, Nanjing 210014, China. Electronic address: zhiqiangx@163.com.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Xu
mesh_terms: D055011:Ablation Techniques; D000595:Amino Acid Sequence; D000818:Animals; D003386:Brachyura / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D010053:Ovary / Q000254:growth & development; D010802:Phylogeny; D021381:Protein Transport; D016415:Sequence Alignment; D013329:Structure-Activity Relationship
chemical_list: D018076:DNA, Complementary; D002265:Carboxylic Ester Hydrolases; C038003:juvenile hormone esterase
keywords: Chinese mitten crab; Juvenile hormone esterase; Methyl farnesoate