Cloning and physical mapping of rRNA genes in Phalaenopsis orchids

• Main Authors: Wen-Ching Lee, 李文靜
• Other Authors: Yen-Yu Kao
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/25171339748978388416

碩士 === 國立臺灣大學 === 植物學研究所 === 90 === Abstract DNA fragments 17~18S - 5.8S — 25~28S and 5S rDNA were cloned from Phalaenopsis aphrodite. The chromosomal localization of these two rDNAs in seven Phalaenopsis species was determined by double target fluorescence in situ hybridization. In this study, we detected (1) two 17~18S - 5.8S — 25~28S rDNA loci and four 5S rDNA loci in P. aphrodite; (2) two 17~18S - 5.8S — 25~28S rDNA loci and two 5S rDNA loci were in P. mannii, P. cornu-cervi and P. lueddemanniana; (3) fourteen 17~18S - 5.8S — 25~28S rDNA loci and two 5S rDNA loci in P. amboinensis; (4) ten 17~18S - 5.8S — 25~28S rDNA loci and two 5S rDNA loci in P. venosa; (5) eight 17~18S - 5.8S — 25~28S rDNA loci and four 5S rDNA loci in P. violacea. P. mannii, P. cornu-cervi and P. lueddemanniana were considered to be closely related according to traditional classification, cytogenetic data and physical mapping of these two rDNAs. Almost all the 17~18S - 5.8S — 25~28S rDNA loci were found in small chromosomes of P. amboinensis, P. venosa and P. violacea. Whether these genes are expressed remains further investigation.