二氢叶酸还原酶基因在斑马鱼咽弓发育过程中作用的研究  

The Effects of Dihydrofolate Reductase Gene on The Development of Pharyngeal Arches

作　　者：孙淑娜[1] 桂永浩[1] 蒋璆[2] 钱林溪[2] 宋后燕[2] 

机构地区：[1]复旦大学儿科医院,上海201102 [2]复旦大学上海医学院生物化学与分子生物学系,分子医学教育部重点实验室,上海200032

出　　处：《生物化学与生物物理进展》2010年第2期145-153,共9页Progress In Biochemistry and Biophysics

基　　金：国家教育部博士点基金资助项目(200802461111)~~

摘　　要：叶酸缺乏可导致胚胎先天性发育异常,二氢叶酸还原酶是叶酸生物学作用通路中的关键因子,其功能阻抑将抑制叶酸生物学作用的发挥.咽弓是脊椎动物胚胎发育中头面部结构、心脏流出道等的共同前体.在模式生物斑马鱼中,利用基因表达阻抑以及过表达技术,探讨二氢叶酸还原酶基因(DHFR)在斑马鱼咽弓发育过程中的作用.石蜡切片以及软骨染色结果显示,DHFR表达阻抑导致斑马鱼咽弓以及腭发育明显异常,而DHFR过表达可部分挽救上述发育异常表型.TBX1和HAND2在咽弓发育中有重要作用.通过胚胎整体原位杂交以及Real-timePCR技术检测TBX1和HAND2表达水平.DHFR表达阻抑后TBX1和HAND2的表达降低,DHFR过表达可使TBX1和HAND2的表达增加.上述结果表明,DHFR在斑马鱼咽弓发育过程中扮演重要角色,DHFR通过影响TBX1和HAND2的表达而调控咽弓的形成和分化.Folic acid deficiency induces congenital malformations.Dihydrofolate reductase（DHFR） plays key roles in folic acid metabolism.The dysfunction of DHFR results in the inhibiting of folic acid.In vertebrate,pharyngeal arches are the progenitor of craniofacial structure and cardiac out flow tract.By using zebrafish as the animal model and coupling with gene knock-down and over-expression technologies,the role of dihydrofolate reductase gene（DHFR） in the development of pharyngeal arches were explored.In DHFR knock-down embryos,the malformations of pharyngeal arches and palates were showed by paraffin section and alcian blue staining.DHFR over-expressing can rescue these malformations.TBX1 and HAND2 are two key transcription factors in the development of pharyngeal arches.Whole-mount in situ hybridization and Real-time PCR were performed to detect the expression levels of TBX1 and HAND2.The expressions of TBX1 and HAND2 were reduced in DHFR knock-down group.DHFR over-expression can increase expressions of TBX1 and HAND2.These results demonstrated that DHFR was essential for the development of pharyngeal arches and DHFR regulated the development of pharyngeal arches by effecting the expressions of TBX1 and HAND2.

关 键 词：二氢叶酸还原酶基因 咽弓 斑马鱼 TBX1 HAND2 

分 类 号：Q3[生物学—遗传学] Q7