中文摘要
甲壳动物成体中,眼柄切除能够刺激雌性和雄性动物的繁殖。在雄性个体中,眼柄切除可以促使甲壳动物促雄性腺产生独特的胰岛素样雄激素(IAG)引起精巢增大。在雌性个体中,眼柄的切除能够加速卵黄的发生,并促进卵巢成熟。另外,眼柄的切除也能够加速甲壳动物的蜕皮,缩短蜕皮周期。眼柄的X-器官窦腺复合体(MTXO-SG)位于眼柄中,被认为是甲壳动物的内分泌调控中心。高血糖激素/蜕皮抑制激素/性腺抑制激素(CHH/MIH/GIH)家族神经肽,是由MTXO-SG分泌的,不同家族成员之间氨基酸序列非常相似,且某些功能相近,但是目前对于眼柄神经肽在调控雄性性别分化中的功能,尚未见任何报道。在眼柄中很可能存在同时能抑制雄性和雌性性腺成熟的因子。本项目拟在甲壳动物眼柄中鉴定控制雄性性别分化,包括控制IAG产生及其下游的级联反应的神经肽,查明甲壳动物性别分化调控控制,为甲壳动物的性别控制提供理论基础。
英文摘要
In mature decapod crustaceans, removal of the eyestalk stimulates reproduction in both sexes. In males, eyestalk ablation stimulates the androgenic gland to produce the unique insulin-like androgenic hormone and results in enlargement of the testis. In females, eyestalk ablation results in rapid vitellogenesis and ovary maturation. In addition to gonad maturation, eyestalk ablation also accelerates the molt cycle of crustaceans.The Medulla Terminalis X-organ Sinus gland (MTXO-SG) is the neuroendocrine center which resides in the crustacean eyestalk. Several neuropeptides belonging to the CHH/MIH/GIH family, sharing similar amino acid sequences and sometime similar functional activities were identified in the MTXO-SG complex, but none were suggested to be engaged in male sex differentiation. It is highly possible that the same factor(s) in the eyestalk are responsible for the inhibition of the males and females gonad maturation. In this proposal we aim at identifying neuropeptide(s) from the eyestalk that control the male sexual differentiation, including the control of the unique gender-specific insulin-like androgenic hormone and it's downstream cascade.
结题摘要
在甲壳动物成体中,眼柄切除能够刺激雌性和雄性动物的繁殖。在雄性个体中,眼柄切除可以促使甲壳动物促雄性腺产生独特的胰岛素样雄激素(IAG)引起精巢增大。在雌性个体中,眼柄的切除能够加速卵黄的发生,并促进卵巢成熟。另外,眼柄的切除也能够加速甲壳动物的蜕皮,缩短蜕皮周期。眼柄的X-器官窦腺复合体(MTXO-SG)位于眼柄中,被认为是甲壳动物的内分泌调控中心。高血糖激素/蜕皮抑制激素/性腺抑制激素(CHH/MIH/GIH)家族神经肽,是由MTXO-SG分泌的,不同家族成员之间氨基酸序列非常相似,且某些功能相近,但是目前对于眼柄神经肽在调控雄性性别分化中的功能,尚未见任何报道。同时,有关IAG与受体作用实现雄性性别分化级联调控的方式也不清楚。在前期研究基础上,本项目从形态上描绘了对虾眼柄的组织结构特征,确定了眼柄中有四种常见的神经分泌细胞;通过比较转录组分析,研究了不同性别及处于不同发育时期、不同蜕皮周期的对虾眼柄基因表达差异,鉴定了多种激素类多肽分子;研究了雌雄性别差异表达神经肽CHH475-1、CHH475-2对对虾促雄性腺素基因IAG的表达调控,初步表明CHH475-1、CHH475-2参与对虾性别分化;鉴定获得了对虾促雄性腺素基因IAG的受体基因IAGR,研究结果显示IAGR特异地在促雄性腺和精巢中表达,转录及蛋白水平IAGR均与IAG之间存在相互作用,并且IAGR基因的沉默导致精巢发育异常,表明IAGR是IAG的受体,在对虾精巢分化过程中发挥重要作用。本项目的研究结果不但丰富了甲壳动物雄性性别分化调控的理论基础,也为甲壳动物的性别控制提供了重要理论支持。
