title: Two transcripts of HMG-CoA reductase related with developmental regulation from Scylla paramamosain: Evidences from cDNA cloning and expression analysis.
abstract: 3-Hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductases (HMGRs), which catalyze the conversion of HMG-CoA to mevalonate, may have an important role in the synthesis of methyl farnesoate (MF). In this study, we obtained two HMGR cDNA sequences termed Sp-HMGR1 (membrane-bound form) and Sp-HMGR2 (soluble form), which encode 967 and 654 amino acids, respectively. The two cDNAs possess entirely identical sequences except that Sp-HMGR1 is 1,382 bp, which encodes a sterol-sensed domain (SSD; a membrane-bound domain) and was first found in crustacean HMGR, larger than Sp-HMGR2. Thus, it was deduced that these cDNAs might be derived from a single genomic DNA sequence. Sp-HMGRs have the typical features of the HMGR class of proteins. However, residue 844 in Sp-HMGR1, which is usually occupied by a Ser residue in other species, has an unusual Ala substitution. This Ser is thought to be involved in enzyme activity regulation by reversible phosphorylation. A putative "PEST" sequence that, until now, has only been found in crustacean species was also identified in the C-terminus of both transcripts, and a sterol-sensing domain, which was first found in crustacean species, was identified in Sp-HMGR1; these findings suggest that Sp-HMGR might function in some special regulatory mechanism. Furthermore, the quantitative real-time polymerase chain reaction results showed that the two transcripts have different expression patterns; Sp-HMGR2 was mainly expressed in the mandibular organ (MO) of adult crabs, whereas Sp-HMGR1 was mainly expressed in other tissues and fertilized eggs up until the fourth juvenile crab stage. The fluctuating gene expression seemed to suggest a relationship between Sp-HMGRs and the development of the crab, especially during the larval stage. Besides, the fluctuation of Sp-HMGR1 in ovary, brain, and thoracic ganglia during the ovary development seemed to have some correlation with the nutrition accumulation of ovaries, whether the SSD domain evolved in this process deserve further investigation. Moreover, it remains unclear whether the significant variation in ovary, brain, and thoracic ganglia during ovary development suggests that other tissues in addition to the MO could synthesize MF.
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.|College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.
authors.forename: Keji
authors.initials: K
authors.lastname: Jiang
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Ma
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.|College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.|College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China.
authors.forename: Yongyong
authors.initials: Y
authors.lastname: Meng
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.|College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China.
authors.forename: Hongqing
authors.initials: H
authors.lastname: Wei
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.
authors.forename: Zhenguo
authors.initials: Z
authors.lastname: Qiao
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.
authors.forename: Fengying
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China.
authors.forename: Lingbo
authors.initials: L
authors.lastname: Ma
mesh_terms: D000818:Animals; D060829:Arthropod Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003386:Brachyura / Q000235:genetics / Q000254:growth & development*; D003001:Cloning, Molecular; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics* / Q000378:metabolism*; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010053:Ovary / Q000254:growth & development; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D060829:Arthropod Proteins; D007527:Isoenzymes; D006903:Hydroxymethylglutaryl CoA Reductases
keywords: 3-hydroxy-3-methylglutaryl-CoA reductase; Scylla paramamosain; adults; crustacean; gene expression; larval; mandibular organ; methyl farnesoate