Ndrg1基因缺失对腰椎到骶椎结构转换的影响  

Loss of Ndrg1 impairs the transition from lumbar to sacral vertebrae

作　　者：陈慧慧[1] 朱煌[1] 郭熙志[1] 

机构地区：[1]上海交通大学Bio-X研究院,教育部遗传发育和神经精神疾病重点实验室,200120

出　　处：《国际骨科学杂志》2015年第3期202-206,217,共6页International Journal of Orthopaedics

基　　金：国家重大基础研究项目(2014CB942902;2012CB966903);国家自然科学基金(31171396;31271553;81121001;31100624;81200586)

摘　　要：目的研究Ndrg1和Ndrg2基因在老鼠脊椎发育过程中的作用。方法以Ndrg1－／－鼠和Ndrg1／2－／－鼠为模型，取胚胎期10．5 d野生型胚胎，应用整体胚胎原位杂交技术确定Ndrg1、Ndrg2基因在小鼠体节的表达谱。取10．5 d的Ndrg1－／－和野生型鼠胚胎，应用整体胚胎原位杂交技术和实时定量聚合酶链式反应（qRT‐PCR）技术检测 Hoxc8、Hoxc9、Hoxc10、Hoxc11基因在体内的表达。将出生后6 d的Ndrg1－／－、Ndrg1／2－／－、野生型鼠窒息处死后，去除皮肤、内脏及结缔组织，对骨架进行阿尔新蓝和茜红素染色，观察小鼠椎体同源转换情况。结果在胚胎期10．5 d ，Ndrg1在颈椎和胸椎体节处显著表达，在腰椎和骶椎体节处表达相对较弱，而Ndrg2在腰椎和骶椎体节处有较强表达，在颈椎和胸椎体节处表达较弱。Ndrg1－／－鼠可育，且无明显生长缺陷。骨架染色结果表明，Ndrg1－／－鼠在L6～S1过渡区域发生椎体同源转变，而在 Ndrg1／2－／－鼠中也发生类似转变。与 Ndrg1－／－或Ndrg2－／－鼠相比，Ndrg1／2－／－鼠在脊椎特性上无叠加缺陷表现。此外，与野生型鼠相比，Ndrg1－／－鼠Hoxc8～11基因表达水平改变。结论 Ndrg1基因在腰椎到骶椎体节过渡区域特化过程中起一定作用，且与Ndrg2基因在脊椎分化过程中无冗余作用。Objective To analysis the role of Ndrg1 and Ndrg2 genes in mouse vertebral development . Methods The mouse models were Ndrg1 -/- and Ndrg1/2 -/- .We conducted whole mount in situ hybridization for embryonic day 10 .5 embryos with digoxin‐labeled Ndrg1 ,Ndrg2 and fibroblast growth factor （FGF）‐8 probes to examine Ndrg1 expression during somitogenesis .We examined the expression patterns of Hoxc8 ,Hoxc9 ,Hoxc10 and Hoxc11 through using whole mount in situ hybridization and quantificational real‐time polymerase chain reaction （qRT‐PCR） at embryonic day 10 .5 embryos of Ndrg1 -/- and wild type .Ndrg1 -/- ,Ndrg1/2 -/- and wild type mice at postnatal day 6 were asphyxiated ,removed the skin ,internal organs and connective tissue ,and then were dyed with Alcian blue and alizarin red .Results The Ndrg1 was strongly expressed in cervical and thoracic somites whereas its expression was relatively weak in lumbar and sacral somites at embryonic day 10 .5 .In contrast ,the expression of Ndrg2 was relatively strong in lumbar and sacral somites but weak in cervical and thoracic somites .The homozygous Ndrg1 -/- mice were viable and fertile with no apparent growth defects .Ndrg1 -/- mice exhibited homeotic transformations in the transitional region from L6 to S1 in axial skeleton .The similar transformation was in the Ndrg1/2 -/- mice .But compared to the Ndrg1 -/- or Ndrg2 -/- mice ,Ndrg1/2 -/- mice had no additional defects .The expression levels of Hoxc8‐11 genes altered in the Ndrg1 -/- mice .Conclusion Ndrg1 gene plays a role in the specification of transitional vertebrae from lumbar to sacral somite ,which is not redundant with Ndrg2 in vertebral differentiation .

关 键 词：NDRG1 体节 脊椎 椎骨同源转换 

分 类 号：R681[医药卫生—骨科学]