Gaiero Paola, van de Belt José, Vilaró Francisco, Schranz M Eric, Speranza Pablo, de Jong Hans
a Department of Plant Biology, Facultad de Agronomía, Universidad de la República, Garzón 780, PC 12900, Montevideo, Uruguay.
b Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, P.O. Box 16, 6708 PB, Wageningen, the Netherlands.
Genome. 2017 Mar;60(3):228-240. doi: 10.1139/gen-2016-0150. Epub 2016 Nov 14.
A major bottleneck to introgressive hybridization is the lack of genome collinearity between the donor (alien) genome and the recipient crop genome. Structural differences between the homeologs may create unbalanced segregation of chromosomes or cause linkage drag. To assess large-scale collinearity between potato and two of its wild relatives (Solanum commersonii and Solanum chacoense), we used BAC-FISH mapping of sequences with known positions on the RH potato map. BAC probes could successfully be hybridized to the S. commersonii and S. chachoense pachytene chromosomes, confirming their correspondence with linkage groups in RH potato. Our study shows that the order of BAC signals is conserved. Distances between BAC signals were quantified and compared; some differences found suggest either small-scale rearrangements or reduction/amplification of repeats. We conclude that S. commersonii and S. chacoense are collinear with cultivated Solanum tuberosum on the whole chromosome scale, making these amenable species for efficient introgressive hybridization breeding.
渐渗杂交的一个主要瓶颈是供体（外来）基因组与受体作物基因组之间缺乏基因组共线性。同源染色体之间的结构差异可能会导致染色体分离不平衡或引起连锁累赘。为了评估马铃薯与其两个野生近缘种（野生马铃薯和查科马铃薯）之间的大规模共线性，我们使用了在RH马铃薯图谱上具有已知位置的序列进行BAC-FISH定位。BAC探针能够成功地与野生马铃薯和查科马铃薯的粗线期染色体杂交，证实了它们与RH马铃薯连锁群的对应关系。我们的研究表明BAC信号的顺序是保守的。对BAC信号之间的距离进行了量化和比较；发现的一些差异表明存在小规模重排或重复序列的减少/扩增。我们得出结论，野生马铃薯和查科马铃薯在整个染色体尺度上与栽培马铃薯是共线性的，这使得这些物种适合进行高效的渐渗杂交育种。
