Co-dominant RAPD Markers Closely Linked with Two Morphological Genes in Rice (Oryza sativa L.)

與水稻型態基因緊密連鎖的共顯性RAPD標記

吳如玉(Ju-Yu Wu) ； 吳信淦(Hsin-Kan Wu) ； 鍾美珠(Mei-Chu Chung)

《Botanical Bulletin of Academia Sinica》 43卷3期 (2002/07) Pp. 171-180

https://doi.org/10.7016/BBAS.200207.0171

摘要

以混合分離族群分析法節選與水稻之兩個形態基因，脆桿(bc-1)及懶散株(la)，連鎖的分子標記。本研究一共節選到四個顯性及二個共顯性的RAPD標記與脆桿(bc-1)基因連鎖，另外有11個顯性與6個共顯性的RAPD標記與懶散株(la)基因連鎖。國爲共顯性的RAPD標記並非尋常，因此將其中與脆桿因距離最近(1.4cM)的兩個共顯性RAPD標記依其苷序列分析數據轉換成SCARs標記。與懶散株(la)基因與連鎖的共顯性RAPD標記間之距離各異，其中兩個比較遠。這些共顯性標記可依其片段大小而區分，核苷序列分析結果顯示兩共顯性片段的差別出現在引子對之間的序列。以電泳分析時，在F1及F2異結合個體之RAPD或SCAR的擴增産物中出現非親本型環帶。經由序列分析、DNA韌合實驗及南方式墨點分析結果顯示，此非親本型環帶爲由等位基因所擴增的異複式DNA片段。非親本型環帶同時也是有共顯性標高的佐證。本研究發現共顯性的RAPD標記,並經確認可實際應用來克服RAPD分子標記本身的限制,利用這些以及將來陸續發現的RAPD分子標記,應有助於基因與圖及基因選殖等工作的進行。

關鍵字

共顯性RAPD標記 ； 基因連鎖 ； 型態基因 ； 水稻

並列摘要

By bulked segregant analysis, we screened for markers linked to two morphological genes, brittle culm (bc-1) and lazy (la). We identified four dominant and two co-dominant RAPD (randomly amplified polymorphic DNA) markers for bc-1 and eleven dominant and six co-dominant RAPD markers for la. One of the co-dominant RAPD markers, located 1.4cM from bc-1, was converted into co-dominant SCAR (sequence characterized amplified region). The six co-dominant markers were linked to la at various distances; two of which spanned a region with many RAPD markers. These co-dominant RAPD markers were detected by size and were a result of sequence modification between, not within, the priming sites. Non-parental bands were observed when the F1 and the heterozygous F2 RAPD and SCAR products were analyzed electrophorectically. Possible reasons for these non-parental bands were examined by sequence analysis, DNA annealing experiments, and Southern hybridization. The results indicated they were heteroduplex DNA formed by identical fragments amplified from allelic sequences. The presence of non-parental bands is further evidence of the co-dominance of the markers of interest. The co-dominant RAPD markers developed in this study overcome many of the limitations of RAPDs, and are readily verifiable and applicable. With these and additional PCR based markers, gene mapping or marker aided selection can be made more efficient.

並列關鍵字

Co-dominant RAPD markers ； Linkage ； Morphological mutant ； Oryza sativa ； SCAR