摘要
生物染色体亚端粒区域在物种进化过程中是高度活跃的。为了认识水稻染色体亚端粒区域的组织结构，用水稻第六染色体长臂亚端粒区的 ＲＦＬＰ标记 Ｇ３４２和 Ｒ１１６７作探针筛选ＢＡＣ文库，以得到的阳性ＢＡＣ克隆为起点进行染色体步行，构建了覆盖这２个分子标记区域约５００ｋｂ的ＢＡＣ跨叠克隆群，将这一区域的遗传图和物理图进行了整合。对１４个ＢＡＣ克隆插入末端进行了亚克隆，鉴定的７个亚克隆末端为单拷贝或低拷贝序列，其中５个定位于Ｇ３４２和Ｒ１１６７的侧翼区域。用覆盖这一区域的ＢＡＣ插入片段作探针对ｃＤＮＡ文库进行初步筛选，获得４个不同的阳性ｃＤＮＡ克隆。
The region between RFLP markers G342 and R1167 was the subterminal part of the longer arm on the rice chromosome 6, because Shen et al. (1998) mapped two telomeric repeat associated sequences distal to G342. In order to integrate the genetic map and the physical map of the region, G342 and R1167 were firstly used to screen BAC library. Based on the positive clones detected by the two markers and chromosome walking by using the outer most insert-end of the overlapping clones, a contig containing 16 BAC clones which spanned 500kb was constructed. All the insert-ends of the BAC clones could be amplified with thermal asymmetric interlaced PCR. Fourteen insert-ends were subcloned. Seven of them were identified as a single or low copy sequences and five were mapped on the expected sites flanking G342 or R1167. The insert fragment isolated from the minimun tile BAC clones of the contig was used to screen a cDNA library and four different positive clones were detected.
基金
国家自然基金!(批准号39630190)
863计划生物技术领域课题
