两栖动物的获得性免疫系统比较脆弱，主要依靠先天免疫系统（多种防御多肽和蛋白组成）承担着抵御环境中各种微生物侵袭的第一道防线，这些防御多肽和蛋白广泛参与神经系统、血液系统和免疫系统等生理功能的调节。因此，科研人员一直致力于从两栖动物皮肤中筛选活性多肽和蛋白作为药物候选分子。我们从云南特有物种普洱泛树蛙皮肤cDNA文库中克隆了3条新颖的抗菌肽和2条蛋白酶抑制剂cDNA序列，BLAST比对结果表明，这5个多肽的一级结构与其它蛙科两栖动物中的类似物同源性很低（55-59%），下一步我们拟测定该树蛙皮肤转录组信息，比对分析后筛选一些结构新颖的多肽/蛋白进行合成/表达，系统开展树蛙防御多肽/蛋白的高级结构和分子机制等方面的研究工作，进而从中挖掘一些具有潜在药用价值的先导分子，为建立我国动物来源药用资源体系奠定基础。

Acquired immune system in amphibians is very fragile.In view of this,it depends on the innate system that is mainly composed of different kinds of defensive peptides and proteins in amphibian skins,the anmphibian skins are key components of the innate immune system of amphibian, and are extensively involve in regulating of nervous system,blood system and immune system.These peptides and proteins are the first line of defense against viral infection upon all amphibian life stages.Therefore,reseach on the skin of frog are hot topic to discover some candidates for therapeutic drugs.Three cDNAs encoding antimicorbial pepptide precursor and two cDNAs encoding serine protease inhibitor precursor have been cloned from the skin of treefrog by us.Blast search results show that they have 55-59% indentities with other amphibians.Based on these work,we hope to characterize the transcriptome of the skin of treefrog,as well as to investigate the structure and function of these novel peptides and proteins, this would help to a better understaning of the molecular mechanism how they could defense potential predators, pathogens, or nonbiological injuries.The further research may lead to discoveries of novel potential lead molecules for pharmaceutical drugs.