光周期对赤点石斑鱼血管囊TSHβ和TSHR基因表达的影响

Effects of Photoperiod on TSHβ and TSHR Gene Expression in Saccus Vasculosus of Epinephelus akaara

本研究考察了光周期对赤点石斑鱼(Epinephelus akaara)血管囊中与光刺激相关基因TSHβ和TSHR表达的影响。运用组织学方法对赤点石斑鱼的血管囊结构进行了观察,运用PCR技术对血管囊中TSHβ和TSHR基因进行克隆和测序,比较了不同光周期(对照组光周期10L∶14D,处理组光周期14L∶10D)对两个基因表达的影响。结果表明:赤点石斑鱼血管囊位于脑垂体后方的间脑下部,在血管囊内部观察到了冠状细胞;赤点石斑鱼TSHβ和TSHR碱基序列与鲈形目鱼种相比具有高度相似性,分别为89%~94%和85%~91%;实验一周后,处理组赤点石斑鱼TSHβ和TSHR基因表达量均显著增加(P<0.05),且显著高于对照组(P<0.05),表明光周期(14L∶10D)条件可能影响赤点石斑鱼TSHβ和TSHR基因的表达。

This study aims to investigate the effects of photoperiod on the gene expression of TSHβ and TSHR in the saccus vasculosus of Epinephelus akaara, which is related to light stimulation. The structure of the saccus vasculosus of E. akaara is observed by histological technology, the TSHβ and TSHR genes are cloned and sequenced by PCR, and their expression of different photoperiods(10 L∶14 D in control group and 14 L∶10 D in treatment group) are compared. The results show that, the saccus vasculosus of E. akaara is located in the lower part of diencephalon behind the pituitary gland, and the coronet cells are observed in the saccus vasculosus. Compared with other species of Perciformes, the base sequences of TSHβ and TSHR in E. akaara have high identities, which are 89%-94% and 85%-91%, respectively. After one week of photoperiod treatment, the TSHβ and TSHR levels in the treatment group significantly increase(P<0.05), and they are significantly higher than those in the control group(P<0.05), suggesting that the photoperiod(14 L∶10 D) may directly affect the expression of TSHβ and TSHR in the saccus vasculosus of E. akaara.