本研究的目的是调查催乳素（PRL）是否通过Hippo信号通路调节信鸽繁殖周期中的喉囊上皮增殖。将24对成年信鸽按照不同繁殖阶段分为四组，并取其喉囊和血清样本。选择18对幼鸽，分为三组进行注射实验。结果显示，孵化17天（I17）和雏鸟哺育第1天（R1）的血清PRL含量和喉囊上皮厚度显著增加。在雄性信鸽中，I17时yes相关转录调节因子（YAP）和蜗牛家族转录抑制因子2（SNAI2）的mRNA水平最高，R1时大肿瘤抑制激酶1（LATS1）、丝氨酸/苏氨酸激酶3（STK3）、TEA结合域转录因子3（TEAD3）、结缔组织生长因子（CTGF）、MYC蛋白原癌基因（c-Myc）和SRY盒转录因子2（SOX2）的基因水平达到最大值。在雌性信鸽中，YAP、STK3、TEAD3和SOX2的基因表达在I17时达到最高水平，SAV1、CTGF和c-Myc的表达谱在R1时达到最大值。在雄性信鸽中，LATS1和YAP的蛋白水平在R1时最高，CTGF表达在I17时上调。在雌性信鸽中，LATS1、YAP和CTGF在I17时达到最大值，磷酸化YAP的表达水平在雄性和雌性的I17时最低。皮下注射催乳素（每天注射6天，每公斤体重10μg）对信鸽左喉囊能通过增加CTGF水平和降低YAP磷酸化水平促进喉囊上皮的增殖。YAP-TEAD抑制剂vertoporfin（每天注射6天，每公斤体重2.5mg）能通过抑制YAP和CTGF的表达来抑制催乳素诱导的喉囊上皮增殖。总之，催乳素可以通过促进Hippo通路中YAP和CTGF的表达参与信鸽喉囊细胞增殖。©作者（2023）。由牛津大学出版社代表美国动物学会出版。保留所有权利。权限问题请通过电子邮件发送至：journals.permissions@oup.com。

The purpose of this study was to investigate whether prolactin (PRL) regulates the proliferation of pigeon crop epithelium through the Hippo signaling pathway during the breeding cycle. 24 pairs of adult pigeons were allotted to four groups by different breeding stages, and their crops and serum were sampled. 18 pairs of young pigeons were selected and divided into three groups for the injection experiments. The results showed that the serum PRL content and crop epithelial thickness of pigeons increased significantly at Day 17 of incubation (I17) and Day 1 of chick-rearing (R1). In males, the mRNA levels of yes associated transcriptional regulator (YAP) and snail family transcriptional repressor 2 (SNAI2) were peaked at I17, and the gene levels of large tumor suppressor kinase 1 (LATS1), serine/threonine kinase 3 (STK3), TEA domain transcription factor 3 (TEAD3), connective tissue growth factor (CTGF), MYC proto-oncogene (c-Myc) and SRY-box transcription factor 2 (SOX2) reached the maximum value at R1. In females, the gene expression of YAP, STK3, TEAD3 and SOX2 reached the greatest level at I17, the expression profile of SAV1, CTGF and c-Myc were maximized at R1. In males, the protein levels of LATS1 and YAP were maximized at R1 and the CTGF expression was up-regulated at I17. In females, LATS1, YAP and CTGF reached a maximum value at I17, and the expression level of phosphorylated YAP was minimized at I17 in males and females. Subcutaneous injection of prolactin (injected for 6 days, 10 μg per kg body weight every day) on the left crop of pigeons can promote the proliferation of crop epithelium by increasing the CTGF level and reducing the phosphorylation level of YAP. YAP-TEAD inhibitor verteporfin (injection for 6 days, 2.5 mg per kg body weight every day) can inhibit the proliferation of crop epithelium induced by prolactin through inhibiting YAP and CTGF expression. In conclusion, PRL can participate in crop cell proliferation of pigeon by promoting the expression of YAP and CTGF in Hippo pathway.© The Author(s) 2023. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.