• 作者： 馮騰永; 郭書祥; 劉麗芳; 林碧玉; 施麗貞; 郭宗德
• 作者服務機構： 中央研究院; 植物研究所
• 中文摘要： 酵母菌質體在宿主內的安定性與質體DNA所含異源序列的多少有關。異源DNA愈少的質體愈安定。本研究採用兩個2μ衍生質體，pMKS I -D和pMKSI-E。兩者的DNA均含一對順向序列。將此類質體送入酵母細胞後，發現在順向序列間會發生同分子間的重組現象，因而產生兩個分子量較小的質體。其中一個子質體的DNA只含非常少（或不含）異源DNA。此類質體在酵母細胞內的安定度大增。
• 英文摘要： Due to the presence of homologous sequences and FLP gene in yeast 2μm-derived plasmid DNAmolecule, intramolecular recombination was demonstrated in the transformed yeast cells (Broach et al.,1982). Although in theory the intermolecular recombination between endogenous 2μm plasmid and in-coming artificial plasmid molecules would recombine with each other, we were unable to find any hybridplasmid resulting from intermolecular recombination. Plasmids pMKSI-D and pMKSl-E contain two selec-tive markers and two copies of inverted repeated sequences (IR2). IR2 sequences are tandem repeated inboth plasmids. FLP provided by endogenous 2μm plasmid directs the specific recombination between twoIR2 in the artificial plasmid such that two plasmids smaller in size were generated. Data from genetic analy-sis revealed that (1) FLP-directed recombination is very specific and is very efficient, (2) plasmid containingless E. coli sequence behaves more stably in yeast. The results indicate that a stable plasmid can be createdby specific intramolecular recombination.
• 中文關鍵字： plasmid; yeast; recombination
• 英文關鍵字： --