Temporal and spatial expression of caudal-type homeobox gene-2 during hindgut development in rat embryos with ethylenethiourea-induced anorectal malformations
Temporal and spatial expression of caudal-type homeobox gene-2 during hindgut development in rat embryos with ethylenethiourea-induced anorectal malformations
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亚乙基硫脲诱发肛门直肠畸形大鼠胚胎后肠发育过程中尾型同源盒基因2的时空表达
DOI：
10.1007/s00441-014-1858-0
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发表时间：
2014-07-01
影响因子：
3.6
通讯作者：
Bai, Yu Zuo
中科院分区：
文献类型：
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作者：
Tang, Xiao Bing;Zhang, Tao;Bai, Yu Zuo
本研究的主要目的是确定Cdx2在正常和肛肠畸形（ARM）胚胎的肛肠发育过程中的表达模式，以期确定Cdx2在ARM发病机制中的可能作用。在妊娠第10天（GD10）用乙烯硫脲诱导大鼠胚胎ARM，并进行剖宫产获取胚胎。研究Cdx2在GD13 ~ GD16期正常大鼠胚胎（n= 303）和ARM胚胎（n= 321）中的时空表达情况。免疫组化染色显示，Cdx2在正常胚胎GD13上主要表达于尿直肠隔（URS）上皮和后肠。GD14时，尿路、后肠和肛肠膜上广泛检测到cdx2免疫阳性细胞。GD15时，肛门膜免疫阳性组织染色明显增加。在ARM胚胎中，泄殖腔、尿路和肛肠上皮Cdx2呈阴性或微弱免疫染色。Western blot和实时反转录加聚合酶链反应分析显示，正常组在发育中的后肠GD13至GD16期间，Cdx2蛋白和mRNA的表达呈时间依赖性变化。在GD15日泄殖腔进入原始直肠和泌尿生殖窦（UGS）后，cdx2表达开始下降。GD13 ~ GD14期间，ARM组cdx2表达水平显著低于正常组（P< 0.05）。在ARM胚胎中，从GD13到GD16的肛肠形态发生过程中，cdx2的时空表达不平衡。因此，cdx2在泄殖腔分离进入原始直肠和UGS时的下调可能与ARM的发展有关。
The main aim of this study was to determine Cdx2 expression patterns during anorectal development in normal and anorectal malformation (ARM) embryos with a view to establishing the possible role of Cdx2 in ARM pathogenesis. ARM was induced with ethylenethiourea on the 10th gestational day (GD10) in rat embryos, and Cesarean deliveries were performed to harvest the embryos. The temporal and spatial expression of Cdx2 was evaluated in normal rat embryos (n= 303) and ARM embryos (n= 321) from GD13 to GD16. Immunohistochemical staining revealed that, in normal embryos, Cdx2 was mainly expressed on the epithelium of the urorectal septum (URS) and the hindgut on GD13. On GD14, Cdx2-immunopositive cells were extensively detected on the URS, hindgut, and cloacal membrane. On GD15, increased immunopositive tissue staining on the anal membrane was evident. In ARM embryos, the epithelium of the cloaca, URS, and anorectum were negative or faintly immunostaining for Cdx2. Analyses by Western blot and real-time reverse transcription plus the polymerase chain reaction revealed that, in the normal group, Cdx2 protein and mRNA expression showed time-dependent changes in the developing hindgut from GD13 to GD16. Upon the URS division of the cloaca into the primitive rectum and urogenital sinus (UGS) on GD15,Cdx2expression began to decrease. Moreover, theCdx2expression level in the ARM group from GD13 to GD14 was significantly lower than that in the normal group (P< 0.05). In ARM embryos, an imbalance in the spatiotemporal expression ofCdx2was noted during anorectal morphogenesis from GD13 to GD16. Downregulation ofCdx2at the time of cloacal separation into the primitive rectum and UGS might thus be related to the development of ARM.