Expression and localization of neural cell adhesion molecule and polysialic acid during chick corneal development.
Expression and localization of neural cell adhesion molecule and polysialic acid during chick corneal development.
复制标题
鸡角膜发育过程中神经细胞粘附分子和聚唾液酸的表达和定位。
DOI：
10.1167/iovs.11-8834
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发表时间：
2012
影响因子：
4.4
通讯作者：
Conrad,GaryW
中科院分区：
文献类型：
--
作者：
Mao,Xiuli;Schwend,Tyler;Conrad,GaryW
目的：目的检测神经细胞粘附分子（NCAM）和多聚唾液酸（polySia）在鸡胚和出生后发育过程中角膜的表达和定位。采用真实的时间定量PCR和Western印迹分析来确定胚胎、幼雏和成年鸡角膜中NCAM的表达和多聚唾液酸化。在胚胎和成人角膜、整个胚胎角膜和三叉神经元的冷冻切片上进行NCAM和polySia的免疫荧光染色。NCAM和ST 8 SiaII mRNA转录在胚胎第9天达到峰值，在E10和E14之间保持稳定，此后在胚胎发育过程中缓慢下降。与E9相比，两种基因转录物在成年鸡角膜中均显示> 190倍的下降。相反，ST 8 SiaIV表达从E6到E19逐渐降低26.5倍，此后增加，并在成人角膜中上升到早期胚胎水平。Western blot分析显示NCAM被多聚唾液酸化，其表达发生了发育性变化。除NCAM外的其他多聚唾液酸化蛋白也通过Western印迹分析检测到。在鸡角膜中存在五种NCAM亚型，包括NCAM-120、NCAM-180和三种具有低分子量（87-96 kDa）的可溶性NCAM亚型，其中NCAM-120是占优势的亚型。NCAM定位于胚胎角膜的上皮、基质和基质细胞外基质（ECM）。在基质中，NCAM表达在胚胎发育过程中从前部转移到后部基质，最终在20周龄的成人角膜中检测不到。此外，在胚胎角膜和角膜周神经上检测到NCAM和polySia。NCAM和polySia在鸡角膜中表达和发育调节。膜相关和可溶性NCAM亚型均在鸡角膜中表达。NCAM和polySia在角膜和角膜神经上的分布表明它们在角膜神经支配中的潜在功能。
Purpose.: To assay for expression and localization of neural cell adhesion molecule (NCAM) and polysialic acid (polySia) in the chick cornea during embryonic and postnatal development.Methods.: Real time quantitative PCR and Western blot analyses were used to determine NCAM expression and polysiaylation in embryonic, hatchling, and adult chick corneas. Immunofluorescence staining for NCAM and polySia was conducted on cryosections of embryonic and adult corneas, whole embryonic corneas, and trigeminal neurons.Results.: NCAM and ST8SiaII mRNA transcripts peaked by embryonic day (E) 9, remained steady between E10 and E14 and slowly decreased thereafter during embryonic development. Both gene transcripts showed> 190-fold decline in the adult chick cornea compared with E9. In contrast, ST8SiaIV expression gradually decreased 26.5-fold from E6 to E19, increased thereafter, and rose to the early embryonic level in the adult cornea. Western blot analysis revealed NCAM was polysialylated and its expression developmentally changed. Other polysiaylated proteins aside from NCAM were also detected by Western blot analysis. Five NCAM isoforms including NCAM-120, NCAM-180 and three soluble NCAM isoforms with low molecular weights (87–96 kDa) were present in chick corneas, with NCAM-120 being the predominate isoform. NCAM was localized to the epithelium, stroma, and stromal extracellular matrix (ECM) of the embryonic cornea. In stroma, NCAM expression shifted from anterior to posterior stroma during embryonic development and eventually became undetectable in 20-week-old adult cornea. Additionally, both NCAM and polySia were detected on embryonic corneal and pericorneal nerves.Conclusions.: NCAM and polySia are expressed and developmentally regulated in chick corneas. Both membrane-associated and soluble NCAM isoforms are expressed in chick corneas. The distributions of NCAM and polySia in cornea and on corneal nerves suggest their potential functions in corneal innervation.