Intra- and intergenomic chromosomal pairing in artificially polyploidized elephant grass and pearl millet hybrids

Abstract: The objective of this work was to evaluate, by genomic in situ hybridization (GISH), pairing configurations as potential indicators of recombination between chromosomes of different parental genomes, in two interspecific hybrids (elephant grass x pearl millet) artificially polyploidized. Anthers from young flower buds were used in the chromosomal preparations. The genomic probe was prepared with pearl millet DNA and labeled with biotin-16-dUTP by the nick translation reaction. Blocking DNA was prepared with genomic elephant grass DNA. The homoeologous intergenomic pairing, observed in the two hybrids, indicates the possibility of recombination between chromosomes of the parental genomes.

摘要：本研究借助基因组原位杂交（genomic in situ hybridization, GISH）技术，对两个经人工多倍体化的种间杂种（象草×珍珠粟）的染色体配对构型进行评估，以其作为不同亲本基因组间染色体重组的潜在指标。实验以幼花蕾的花药作为染色体制备材料；基因组探针采用珍珠粟DNA制备，并通过缺口平移反应标记生物素-16-脱氧尿嘧啶三磷酸（biotin-16-dUTP）；封闭DNA则由象草基因组DNA制备。在两个杂种中均观察到部分同源基因组间配对现象，这表明亲本基因组的染色体之间存在重组的可能性。