title: Leptin and its receptor in turbot Scophthalmus maximus: cloning, characterization and expression response to ratios of dietary carbohydrate-lipid.
abstract: In the present study, the full-length cDNA sequences of leptin (LEP) and its receptor (LEPR) from turbot Scophthalmus maximus were cloned. The cDNA of tLEP was 1126 bp in length encoding 157 amino acids. The amino acid sequence shared low identity with human LEP (18.8 %), but the three-dimensional structures of these two LEPs were strongly conserved. The deduced 1173-amino acid sequence of tLEPR was 28 % identical to human LEPR, and 82 % too range-spotted grouper LEPR, containing all functionally important domains conserved in vertebrate LEPR. Tissue distribution analysis showed that tLEP was abundantly expressed in brain, eyes and liver. The highest level of tLEPR mRNA was found in liver and kidney. After a 9-week feeding trial using diets with different ratios of carbohydrate-lipid (1:6, 1:2, 2:1 and 14:1), it was found that the increase in dietary carbohydrate-to-lipid ratios from 1:6 to 2:1 did not significantly influence tLEP and tLEPR expression in turbot liver (P > 0.05). The hepatic tLEP expression was significantly elevated in treatment with 14:1 dietary carbohydrate-to-lipid ratio (P < 0.05). The hepatic tLEPR mRNA level in group with 14:1 dietary carbohydrate-to-lipid ratio was significantly lower than that in 1:6 group (P < 0.05), but had no significant difference with the other two groups (P > 0.05). These results revealed the important relationship between dietary carbohydrate-to-lipid ratio and LEP expression in turbot.
authors.affiliation: The Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, Ocean University of China, Qingdao, China.|The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, China.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Han
authors.affiliation: The Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, Ocean University of China, Qingdao, China.|The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, China.
authors.forename: Huijun
authors.initials: H
authors.lastname: Miao
authors.affiliation: The Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, Ocean University of China, Qingdao, China.|The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Nie
authors.affiliation: The Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, Ocean University of China, Qingdao, China.|The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, China.
authors.forename: Shuyan
authors.initials: S
authors.lastname: Miao
authors.affiliation: Guangxi Institute of Oceanology, Key Laboratory of Marine Biotechnology of Guangxi, Beihai, 536000, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: The Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, Ocean University of China, Qingdao, China. wzhang@ouc.edu.cn.|The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, China. wzhang@ouc.edu.cn.
authors.forename: Wenbing
authors.initials: W
authors.lastname: Zhang
authors.affiliation: The Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, Ocean University of China, Qingdao, China.|The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, China.
authors.forename: Kangsen
authors.initials: K
authors.lastname: Mai
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004041:Dietary Fats / Q000494:pharmacology*; D029941:Fish Proteins / Q000235:genetics*; D005412:Flatfishes / Q000235:genetics*; D015870:Gene Expression; D020738:Leptin / Q000235:genetics*; D008099:Liver / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D054411:Receptors, Leptin / Q000235:genetics*
chemical_list: D018076:DNA, Complementary; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D029941:Fish Proteins; D020738:Leptin; D012333:RNA, Messenger; D054411:Receptors, Leptin
keywords: Carbohydrate; Leptin; Leptin receptor; Lipid; Turbot