产蛋间隔期母鸽卵黄前体及其受体基因的表达分析

Expression analysis of yolk precursors and receptor genes in female pigeons during egg laying interval

旨在探究产蛋间隔期鸽卵黄沉积相关基因的表达规律。选取12月龄白羽王鸽48对,分别在产蛋间隔(LI)第1天(LI1)、第3天(LI3)、第5天(LI5)和第7天(LI7)4个时期采集母鸽肝脏、卵巢、F1卵泡颗粒层和F1卵泡膜层样本,利用实时荧光定量PCR(RT-qPCR)检测载脂蛋白B(APOB)、载脂蛋白极低密度脂蛋白Ⅱ(APO-VLDLⅡ)、卵黄蛋白原(VTG)2和极低密度脂蛋白受体(VLDLR)4种基因的表达规律。结果:肝脏中APOB的表达水平呈下降趋势,在LI7期达到最低,与LI1和LI3期差异显著(P<0.05);APO-VLDLⅡ在LI1期表达水平最高,呈先下降后上升再下降趋势,在LI3和LI7期达到最低,与LI1和LI5期差异极显著(P<0.01);VTG2的表达水平呈上升趋势,在LI7期达到最高,与LI1、LI3和LI5期差异极显著(P<0.01)。卵巢中VLDLR的表达水平呈先下降后上升再下降趋势,在LI3时达到最高,与LI1、LI5和LI7期差异极显著(P<0.01);颗粒细胞层中VLDLR表达水平呈先下降后上升趋势,在LI3期达到最低,与LI5和LI7期差异极显著(P<0.01);膜细胞层中VLDLR的表达水平呈先上升后下降趋势,在LI5期达到最高,与LI3期差异显著(P<0.05)。综上,产蛋间隔前期APOB和APO-VLDLⅡ表达水平较高,启动载脂蛋白合成和运输,后期卵黄沉积减缓,APOB和APO-VLDLⅡ表达水平下降,同时雌激素诱导VTG2表达水平上升;产蛋间隔前期卵巢VLDLR表达水平较高,介导吸收卵黄前体物质,后期颗粒细胞层和膜细胞层VLDLR表达水平较高,介导卵黄前体进入卵泡最终形成卵黄。

The aim of this study was to analyze the expression of genes related to yolk deposition in pigeons during the interval of laying eggs.Forty-eight pairs of 12-month-old royal pigeons were selected.On laying day 1(LI1),day 3(LI3),day 5(LI5)and day 7(LI7)of the laying interval(LI),The samples of liver,ovary,F1 follicular granulosa layer and F1 follicular membrane layer were collected from the pigeons.Then,the expression patterns of apolipoprotein B(APOB),apolipoprotein very low density lipoproteinⅡ(APO-VLDLⅡ),vitellinogen(VTG2)and very low density lipoprotein receptor(VLDLR)were detected by RT-qPCR.The results showed as follows:The expression level of APOB in the liver showed a decreasing trend,and reached the lowest level in the LI7 stage;the difference being signifi⁃cant(P<0.05).The expression level of APO-VLDLⅡin the liver was the highest in the LI1 stage,decreasing first,increasing then and decreasing again,and reaching the lowest in the LI3 and LI7 stages,with a very significant difference(P<0.01).The expression level of VTG2 in the liver showed an increasing trend,reaching the highest level in the LI7 stage,a very significant difference(P<0.01).The expression level of VLDLR in the ovarian increased first and then decreased,reaching the highest level in the LI3 stage,with a very significant difference(P<0.01).The expression level of VLDLR in the granular cell layer decreased first and then increased,reaching the lowest level in the LI3 stage,with a very significant difference(P<0.01).The expression level of VLDLR in the membrane layer decreased first,increased then and decreased again,reaching the highest level in the LI5 stage,with a significant difference(P<0.05).To sum up,the·8·Animal Husbandry&Veterinary Medicine 2024 Vol.56 No.10 expression levels of APOB and APO-VLDLⅡwere high in the early stage of the laying interval,which initiated apolipoprotein synthesis and transport,and the yolk deposition was slowed down in the later stage.The expression levels of APOB and APO-VLDLⅡdecreased,while estrogen induced the increase of VTG2 expression.In the early stage of the laying interval,the expression level of VLDLR in the ovary was higher,which mediated the absorption of yolk precursors.In the late stage,the expression level of VLDLR in the granular cell layer and the membrane cell layer was higher,which mediated the entry of yolk precursors into the follicle and finally the formation of yolk.