Targeted disruption of TORC1 retards young squab growth by inhibiting the synthesis of crop milk protein in breeding pigeon (Columba livia).
Targeted disruption of TORC1 retards young squab growth by inhibiting the synthesis of crop milk protein in breeding pigeon (Columba livia).
复制标题
Torc1的靶向破坏通过抑制繁殖鸽子（哥伦比亚利维亚）中农作牛奶蛋白的合成来抑制年轻的异类生长。
DOI：
10.3382/ps/pez513
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发表时间：
2020-01
期刊：
影响因子：
4.4
通讯作者：
Gao CQ
中科院分区：
文献类型：
--
作者：
Chen MJ;Fu Z;Jiang SG;Wang XQ;Yan HC;Gao CQ
本研究旨在探讨雷帕霉素复合物1（TORC1）靶标信号通路在种鸽（Columba livia）作物乳汁合成中的调节作用。三组哺乳期种鸽（n = 30对/组）分别经翼静脉注射雷帕霉素（RAPA，雷帕霉素复合物靶标的特异性抑制剂），剂量为0（载体，对照）、0.6或1.2 mg/kg体重（BW）/天，持续7天。整个实验期间分别记录种鸽的平均日采食量（ADFI）和体重以及幼鸽的体重。在实验的第八天，处死种鸽以收集其嗉囊组织、嗉囊乳和血清。结果表明，注射0.6和1.2 mg/kg BW RAPA均不影响种鸽的体重损失或ADFI（P > 0.05），而注射1.2 mg/kg BW雷帕霉素组嗉囊厚度和嗉囊相对重量显着降低（P < 0.05）。同时，RAPA（尤其是 1.2 mg/kg BW）降低了农作物乳中的粗蛋白、αs1-酪蛋白、αs2-酪蛋白、β-酪蛋白和氨基酸含量（Asp、Thr、Ser、Glu、Gly、Ala、Cys、Val、Met、Ile、Leu、Tyr、Lys、His、Arg 和 Pro）（P < 0.05）以及总白蛋白浓度。种鸽血清中蛋白质、尿酸的变化（P < 0.05）。此外，注射 0.6 或 1.2 mg/kg BW/天 RAPA 后，种鸽嗉囊组织中 TORC1 通路相关蛋白（TORC1、S6K1、S6、4EBP1 和 eIF4E）的表达下调（P < 0.05）。相应地，幼雏乳鸽的平均日增重（ADG）下降，死亡率显着上升（P < 0.05）。总之，结果表明 RAPA 降低了种鸽嗉囊乳中的蛋白质和氨基酸水平，并延缓了幼鸽的生长，这表明 TORC1 在种鸽嗉囊奶合成中发挥着至关重要的作用。
This study was conducted to explore the regulatory role of the target of rapamycin complex 1 (TORC1) signaling pathway in crop milk synthesis in breeding pigeons (Columba livia). Three groups of breeding pigeons in the lactation period (n = 30 pairs/group) were respectively injected with rapamycin (RAPA, a specific inhibitor of the target of rapamycin complex) at doses of 0 (vehicle, control), 0.6, or 1.2 mg/kg body weight (BW)/day via the wing vein for 7 days. The average daily feed intake (ADFI) and BW of the breeding pigeons and the BW of young squabs were respectively recorded throughout the experimental period. The breeding pigeons were sacrificed to collect their crop tissues, crop milk, and serum on the eighth day of the experiment. The results showed that neither 0.6 nor 1.2 mg/kg BW RAPA injection affected BW loss or ADFI in breeding pigeons (P > 0.05), while crop thickness and crop relative weight were significantly decreased (P < 0.05) in the 1.2 mg/kg BW rapamycin-injected group. Simultaneously, RAPA (especially at 1.2 mg/kg BW) decreased the crude protein, αs1-casein, αs2-casein, β-casein, and amino acid contents (Asp, Thr, Ser, Glu, Gly, Ala, Cys, Val, Met, Ile, Leu, Tyr, Lys, His, Arg, and Pro) of crop milk (P < 0.05) and the concentrations of albumin, total protein, and uric acid in the serum of breeding pigeons (P < 0.05). Additionally, the expression of TORC1 pathway-related proteins (TORC1, S6K1, S6, 4EBP1, and eIF4E) was downregulated in the crop tissues of breeding pigeons by 0.6 or 1.2 mg/kg BW/day RAPA injection (P < 0.05). Accordingly, the average daily gain (ADG) of young squabs declined, and the mortality rate increased significantly (P < 0.05). Together, the results showed that RAPA reduced protein and amino acid levels in the crop milk of breeding pigeons and retarded young squab growth, suggesting a crucial role of TORC1 in crop milk synthesis in breeding pigeons.