【摘要】 目的 :探讨大鼠 β -防御素 - 2基因在肺组织表达的发育调控。方法 :根据Genbank大鼠 β -防御素- 2的cDNA序列 ,设计一对特异引物。采用RT -PCR技术在大鼠不同发育阶段的肺组织总RNA中 ,扩增其特异cDNA片段 ,并进行DNA序列测定。借助Genbank中BLAST程序 ,将从该cDNA序列推导的氨基酸序列与人的hBD -2和大鼠的rBD - 1做相似性分析。结果 :从足月胎鼠、出生 8h和 4d以及成年大鼠相同重量肺组织所提取的总RNA中 ,均扩增出一条密度相同、长度约为 2 2 0bp的cDNA片段。在所推导氨基酸序列中与hBD - 2氨基酸相同率为48 6 % (17/ 35 ) ,与rBD - 1氨基酸残基的相同率为 31% (11/ 35 )。其成熟分子链长 35个氨基酸残基 ,含 β -防御素共有的且排列次序相同的 6个典型的半胱氨酸和其它保守氨基酸残基。结论 :本实验表明不同发育阶段大鼠肺组织均表达β - 防御素 - 2mRNA ,提示该分子可能是肺组织天然抵抗微生物感染的一个重要分子基础更多还原

【Abstract】 AIM: To investigate the developmental regulation of β-defensin rBD-2 gene expression in the rat lung. METHOD: Total RNA was isolated from the pulmonary tissues of the fetal, neonatal and adult rats. RT-PCR were performed with primers (P 1: TTCAGTCATGAGGATCCATT AC; P 2: TGGAACTTGGTCTTTTTATCTAC). The RT-PCR products were cloned into pGEM-T easy vector and the recombinant plasmid was analyzed with EcoR1 digestion and the inserted DNA sequencing was performed on ABI PRISM-377 DNA sequencer. RESULTS: Rat β-defensin-2 transcripts were detected in all the pulmonary tissues of rats during different developmental stages, e.g. at just before birth, 8 hours and 4 days after birth , and adult. CONCLUSION: The rat β-defensin-2 is constitutively expressed in the pulmonary tissues, suggesting that β-defensin-2 may play a role in the lung innate defense against infection.更多还原