Isolation and physical mapping of (GA)n microsatellites in Phalaenopsis cornu-cervi

• Main Authors: Ling-Chiao Wu, 吳淩巧
• Other Authors: 高燕玉
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/67363092189487843066

碩士 === 國立臺灣大學 === 分子與細胞生物學研究所 === 97 === Microsatellites are highly abundant in eukaryotic genomes. Eleven (GA)n microsatellite-containing clones were isolated from Phalaenopsis cornu-cervi by single-primer PCR using (GA)11 as a primer. The size of sequences varied from 120 to 860 bp and the average sequence identity for those was 54.45%. Sequence homology searches of the TIGR database revealed similarities with repetitive sequences in many plants. Seven clones, W8-4, W8-5, W8-18, W8-35, and W8-41 from P. cornu-cervi, DpGA2 from P. pulcherrima, and W40-19 from P. stuartiana, were all mapped in the metaphase chromosomes of P. cornu-cervi by fluorescence in situ hybridization (FISH). All signals were similar in intensity and clustered in the centromeric regions of all chromosomes. It was found a quite exceptional distribution of DpGA2 probe which was only located in the centromeric regions of one chromosome pair of P. pulcherrima. The hybridization signals of the clone W8-18 were also clustered in the centromeric regions of P. mannii, P. pulcherrima, and P. stuartiana chromosomes. In addition, signals were much stronger in P. stuartiana than in other species. These results were consistent with the physical mapping of synthetic oligonucleotides (GA)11 in the previous study.