Fernandez-Silva I, Eduardo I, Blanca J, Esteras C, Picó B, Nuez F, Arús P, Garcia-Mas J, Monforte Antonio José
IRTA, Centre de Recerca en Agrigenòmica CSIC-IRTA-UAB (CRAG), Carretera de Cabrils, Km 2, 08348, Cabrils, Barcelona, Spain.
Theor Appl Genet. 2008 Dec;118(1):139-50. doi: 10.1007/s00122-008-0883-3. Epub 2008 Sep 20.
We report the development of 158 primer pairs flanking SSR motifs in genomic (gSSR) and EST (EST-SSR) melon sequences, all yielding polymorphic bands in melon germplasm, except one that was polymorphic only in Cucurbita species. A similar polymorphism level was found among EST-SSRs and gSSRs, between dimeric and trimeric EST-SSRs, and between EST-SSRs placed in the open reading frame or any of the 5'- or 3'-untranslated regions. Correlation between SSR length and polymorphism was only found for dinucleotide EST-SSRs located within the untranslated regions, but not for trinucleotide EST-SSRs. Transferability of EST-SSRs to Cucurbita species was assayed and 12.7% of the primer pairs amplified at least in one species, although only 5.4% were polymorphic. A set of 14 double haploid lines from the cross between the cultivar "Piel de Sapo" and the accession PI161375 were selected for the bin mapping approach in melon. One hundred and twenty-one SSR markers were newly mapped. The position of 46 SSR loci was also verified by genotyping the complete population. A final bin-map was constructed including 80 RFLPs, 212 SSRs, 3 SNPs and the Nsv locus, distributed in 122 bins with an average bin length of 10.2 cM and a maximum bin length of 33 cM. Map density was 4.2 cM/marker or 5.9 cM/SSR.
我们报告了在甜瓜基因组（gSSR）和EST（EST-SSR）序列中侧翼为SSR基序的158对引物对的开发情况，除了一对仅在南瓜属物种中具有多态性外，所有引物对在甜瓜种质中均产生多态性条带。在EST-SSR和gSSR之间、二聚体和三聚体EST-SSR之间以及位于开放阅读框或任何5'-或3'-非翻译区的EST-SSR之间发现了相似的多态性水平。仅在位于非翻译区内的二核苷酸EST-SSR中发现了SSR长度与多态性之间的相关性，而三核苷酸EST-SSR则未发现。对EST-SSR向南瓜属物种的可转移性进行了检测，12.7%的引物对至少在一个物种中扩增，尽管只有5.4%是多态性的。从品种“Piel de Sapo”与种质PI161375的杂交后代中选择了一组14个双单倍体系用于甜瓜的区间作图方法。新定位了121个SSR标记。通过对整个群体进行基因分型，还验证了46个SSR位点的位置。构建了一个最终的区间图谱，包括80个RFLP、212个SSR、3个SNP和Nsv位点，分布在122个区间中，平均区间长度为10.2 cM，最大区间长度为33 cM。图谱密度为4.2 cM/标记或5.9 cM/SSR。
