Identification and functional characterization of gonadotropin -releasing hormone in pompano (Trachinotus ovatus)

Xilin Ren; Yanlin Huang; Xiaomeng Li; Zhiyuan Li; Hao Yang; Ruiqi He; Honggan Zhong; Guangli Li; Huapu Chen

doi:10.1016/j.ygcen.2021.113958

Identification and functional characterization of gonadotropin -releasing hormone in pompano (Trachinotus ovatus)

Gen Comp Endocrinol. 2022 Jan 15:316:113958. doi: 10.1016/j.ygcen.2021.113958. Epub 2021 Nov 30.

Authors

Xilin Ren¹, Yanlin Huang², Xiaomeng Li², Zhiyuan Li², Hao Yang², Ruiqi He², Honggan Zhong³, Guangli Li², Huapu Chen⁴

Affiliations

¹ Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang 524025, China.
² Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China.
³ Key Laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China.
⁴ Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang 524025, China; Key Laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China. Electronic address: chenhp@gdou.edu.cn.

PMID: 34861278
DOI: 10.1016/j.ygcen.2021.113958

Abstract

Gonadotropin-releasing hormone (GnRH) is an important neuropeptide in the reproductive system. Although GnRH analogues have been used to artificially spawn pompano (Trachinotus sp.), the native forms of GnRH have not been described in this species. In this study three GnRH subtypes [sea bream GnRH (sbGnRH), chicken GnRH-Ⅱ (cGnRH-Ⅱ) and salmon GnRH (sGnRH)] were identified in pompano (Trachinotus ovatus). cgnrh-Ⅱ and sgnrh were mainly expressed in the brain of male and female fish, showing a tissue-specific expression pattern, while sbgnrh was expressed at different transcriptional levels in all tested tissues. In vivo injection experiment showed that sbGnRH significantly increased fsh and lh genes expression in a dose-dependent manner, but a high concentration of sbGnRH could desensitize the expression of lh. High concentrations of cGnRH-Ⅱ and sGnRH could induce the expression of fsh and lh. In addition, the results of in vitro incubation experiments showed that the high concentration of sbGnRH peptide could induce the expression of fsh and lh, while cGnRH-Ⅱ and sGnRH peptides could only induce the expression of fsh. 17β-estradiol (E₂) and 17α-methyltestosterone (MT) significantly inhibited sbgnrh mRNA expression in a dose-dependent manner, but did not affect the expression of cgnrh-Ⅱ and sgnrh mRNA. sbGnRH is the main GnRH subtype in pompano. E₂ and MT can play a negative role in the regulation of sbgnrh. This study provides a theoretical basis for the reproductive endocrinology of pompano.

Keywords: Feedback regulation; Gonadotropin-releasing hormone; Reproduction; Trachinotus ovatus.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Female
Fishes / metabolism
Gonadotropin-Releasing Hormone / metabolism
Gonadotropins / metabolism
Male
Perciformes* / metabolism
Pituitary Gland* / metabolism

Substances

Gonadotropins
Gonadotropin-Releasing Hormone