Vitellogenesis is the main event of oocyte growth in oviparous animals,which is mainly manifested by the accumulation of vitellogenin(VTG).The accumulation of vitellogenin depends mainly on the absorption of exogenous...Vitellogenesis is the main event of oocyte growth in oviparous animals,which is mainly manifested by the accumulation of vitellogenin(VTG).The accumulation of vitellogenin depends mainly on the absorption of exogenous vitellogenin,which enters oocyte through endocytosis mediated by its receptor(VGR).We investigated the expression and localization of VTG and VGR during gonad development of Pampus argenteus.The qPCR results show that vtgs were not expressed in male fish,but in the ovary and liver of female fish;the expression levels went up at first and then down.The expression levels of vgr in the testis were low and only 1%-3%of that in ovary.ELISA results show that during the ovarian development of P.argenteus,VTG in liver,serum,and ovary all showed a trend from increasing to decreasing.However,VTG in liver peaked in StageⅣ,and in serum and ovary peaked in Stage V,reflecting changes in the characteristics of VTG in the liver(synthesis),blood(transport),and ovaries(accumulation).During gonad development,VGR in the ovaries first increased and then decreased,reaching a peak in Stage V,in contrast to vgr mRNA expression.The VGR content in the testis was extremely low and stable,consistent with vgr mRNA.Immunohistochemistry results show that the location and intensity of VTG and VGR positive signals were synchronized with the changes of their protein content,which revealed that VTG was mainly synthesized in the liver cytoplasm,secreted into the blood,and transported to ovary in StageⅢ.VGR is highly expressed in oocytes in StageⅡ.In StageⅢ,a large amount of VTG reaches the ovary,when VGR begins to translate and is subsequently transported to the plasma membrane of the oocyte.Therefore,the positive signal of VGR was stronger near the plasma membrane of oocytes in StagesⅠandⅡ.By using qPCR,ELISA,and immunohistochemistry,the synthesis,transport,and accumulation of vitellogenin were elucidated and the mechanism of its endocytosis on egg membrane mediated by VTG during the development of P.argenteus was revealed preliminarily.展开更多
为了阐明卵黄蛋白原基因对溞属枝角类生殖和胚胎发育的影响机制,研究了RNA干扰下中华拟同形溞(Daphnia sinensis)的卵黄蛋白原基因表达及产幼溞数变化。结果表明,RNA干扰后,与EGFP(Enhanced green fluorescent protein)组相比,2%大肠杆...为了阐明卵黄蛋白原基因对溞属枝角类生殖和胚胎发育的影响机制,研究了RNA干扰下中华拟同形溞(Daphnia sinensis)的卵黄蛋白原基因表达及产幼溞数变化。结果表明,RNA干扰后,与EGFP(Enhanced green fluorescent protein)组相比,2%大肠杆菌浓度下中华拟同形溞在Vtg组的首次产幼溞数和Vtg基因相对表达量没有显著差异;5%大肠杆菌浓度下中华拟同形溞前四个成龄在Vtg组的产幼溞数均显著小于EGFP组,且中华拟同形溞的第一成龄、第四成龄时在Vtg组的Vtg基因相对表达量均显著小于EGFP组,分别下降了5.25%和78.03%。此外,RNA干扰后Vtg组的中华拟同形溞还出现了胚胎消解和后代发育不全的现象。结果表明,高强度、长时间的RNA干扰能够显著降低中华拟同形溞Vtg基因的相对表达水平,也能够显著抑制其生殖量和胚胎发育。因此,Vtg基因对中华拟同形溞的生殖和胚胎发育起重要作用。展开更多
基金Supported by the National Natural Science Foundation of China(Nos.31872586,42076118)the Major Project of Science,Technology and Innovation 2025 in Ningbo City(No.2021Z003)the K.C.Wong Magna Fund in Ningbo University。
文摘Vitellogenesis is the main event of oocyte growth in oviparous animals,which is mainly manifested by the accumulation of vitellogenin(VTG).The accumulation of vitellogenin depends mainly on the absorption of exogenous vitellogenin,which enters oocyte through endocytosis mediated by its receptor(VGR).We investigated the expression and localization of VTG and VGR during gonad development of Pampus argenteus.The qPCR results show that vtgs were not expressed in male fish,but in the ovary and liver of female fish;the expression levels went up at first and then down.The expression levels of vgr in the testis were low and only 1%-3%of that in ovary.ELISA results show that during the ovarian development of P.argenteus,VTG in liver,serum,and ovary all showed a trend from increasing to decreasing.However,VTG in liver peaked in StageⅣ,and in serum and ovary peaked in Stage V,reflecting changes in the characteristics of VTG in the liver(synthesis),blood(transport),and ovaries(accumulation).During gonad development,VGR in the ovaries first increased and then decreased,reaching a peak in Stage V,in contrast to vgr mRNA expression.The VGR content in the testis was extremely low and stable,consistent with vgr mRNA.Immunohistochemistry results show that the location and intensity of VTG and VGR positive signals were synchronized with the changes of their protein content,which revealed that VTG was mainly synthesized in the liver cytoplasm,secreted into the blood,and transported to ovary in StageⅢ.VGR is highly expressed in oocytes in StageⅡ.In StageⅢ,a large amount of VTG reaches the ovary,when VGR begins to translate and is subsequently transported to the plasma membrane of the oocyte.Therefore,the positive signal of VGR was stronger near the plasma membrane of oocytes in StagesⅠandⅡ.By using qPCR,ELISA,and immunohistochemistry,the synthesis,transport,and accumulation of vitellogenin were elucidated and the mechanism of its endocytosis on egg membrane mediated by VTG during the development of P.argenteus was revealed preliminarily.
文摘为了阐明卵黄蛋白原基因对溞属枝角类生殖和胚胎发育的影响机制,研究了RNA干扰下中华拟同形溞(Daphnia sinensis)的卵黄蛋白原基因表达及产幼溞数变化。结果表明,RNA干扰后,与EGFP(Enhanced green fluorescent protein)组相比,2%大肠杆菌浓度下中华拟同形溞在Vtg组的首次产幼溞数和Vtg基因相对表达量没有显著差异;5%大肠杆菌浓度下中华拟同形溞前四个成龄在Vtg组的产幼溞数均显著小于EGFP组,且中华拟同形溞的第一成龄、第四成龄时在Vtg组的Vtg基因相对表达量均显著小于EGFP组,分别下降了5.25%和78.03%。此外,RNA干扰后Vtg组的中华拟同形溞还出现了胚胎消解和后代发育不全的现象。结果表明,高强度、长时间的RNA干扰能够显著降低中华拟同形溞Vtg基因的相对表达水平,也能够显著抑制其生殖量和胚胎发育。因此,Vtg基因对中华拟同形溞的生殖和胚胎发育起重要作用。
