不同胚期B6-Co小鼠眼睑组织中血清反应因子的表达变化

摘要

背景 C57BL/6角膜混浊表型的突变系(B6-Co)小鼠具有出生眼睑闭合不全(EOB)表型,是研究眼睑发育机制的良好动物模型.探讨血清反应因子(SRF)与B6-Co小鼠EOB表型形成的关系可为人类先天性眼睑发育缺陷产生机制的研究提供理论依据.目的 检测SRF在B6-Co小鼠胚胎眼睑发育关键时期的表达.方法 采用肌内注射戊巴比妥钠安乐死术,分别剖取B6-Co母鼠以及表型正常B6母鼠体内胚胎期(E)16.5 d、E17.5 d和E18.5 d小鼠各9只,分离眼睑组织,分别采用实时定量PCR法和Western blot法检测小鼠眼睑组织中SRF mRNA及其蛋白的相对表达水平.取各胎龄的B6-Co小鼠和B6小鼠制作组织冰冻切片,利用免疫荧光技术检测并比较2种小鼠SRF在眼睑组织中的定位和表达强度.结果 B6-Co小鼠E16.5 d和E17.5 d眼睑组织中SRF mRNA的相对表达水平分别为0.41±0.06和0.24±0.17,明显低于B6小鼠的1.03±0.17和1.01±0.09,差异均有统计学意义(P=0.025、0.017);B6-Co小鼠E16.5 d和E17.5 d眼睑组织中SRF蛋白的表达水平分别为0.08±0.01和0.08±0.01,明显低于B6小鼠的0.12±0.03和0.13 ±0.02,差异均有统计学意义(P=0.036、0.024);而2种小鼠间E18.5 d时眼睑组织中SRF mRNA及其蛋白的表达量差异均无统计学意义(P=0.387、0.774).免疫荧光染色显示,SRF蛋白多表达于B6-Co小鼠和B6小鼠眼睑组织的角质层细胞,但B6-Co小鼠眼睑角质形成细胞中SRF蛋白表达的荧光强度明显弱于B6小鼠.结论 SRF在B6-Co小鼠眼睑组织中的表达量明显下调,SRF可能参与眼睑发育缺陷的发生过程.%Background Mutant C57BL/6 mouse with corneal opacity (B6-Co) appears eye open at birth (EOB) phenotype,which is a good animal model in the study of developmental mechanism of eyelid.Investigating the relationship between serum response factor (SRF) and EOB phenotype can provide theoretical support for the research on the mechanism of innate defects in eyelid development in humans.Objective This study was to assess the dynamic expressions of SRF in eyelid of embryonic B6-Co mouse.Methods Total RNA was extracted from B6 and B6-Co mice eyelid tissue at embryonic day 16.5 (E16.5 d),E17.5 d and E18.5 d.The relative expression levels of SRF mRNA and protein in the eyelid tissue of B6 and B6-Co embryonic mice were assayed by real-time quantitative PCR and Western blot,respectively.In situ expressions of SRF protein in eyelid of B6-Co mice and B6 mice were detected using immunofluorescence technique.The use and care of the animals complied with the Regulation for the Administration of Affair Concerning Experimental Animals of Nantong University.Results The relative expression levels ofSRF mRNA in the eyelids were 0.41±0.06 and 0.24±0.17 in E16.5 d and E17.5 d of B6-Co mice,showing a significant decline in comparison with 1.03 ±0.17 and 1.01 ±0.09 in the B6 mice (P =0.025,0.017).The expression levels of SRF protein in the eyelids of E16.5 d and E17.5 d B6-Co mice were 0.08±0.01 and 0.08± 0.01,which were significantly lower than 0.12 ±0.03 and 0.13 ± 0.02 of B6 mice (P =0.036,0.024).However,there were no significant differences in the expression levels of SRF mRNA and protein in E18.5 d between the B6-Co mice and B6 mice (P =0.387,0.774).Immunofluorescence assay displayed that SRF was expressed in the keratinocytes of eyelids in both mice,but the fluorescence intensity was weaker in the B6-Co mice.Conclusions SRF probably interrupts the developing process of eyelid in early embryo of B6-Co mice.