The genome organization and diversification of maize and its allied species revisited: evidences from classical and FISH-GISH cytogenetic analysis
The genome organization and diversification of maize and its allied species revisited: evidences from classical and FISH-GISH cytogenetic analysis
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DOI：
10.1159/000082408
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发表时间：
2005-03
影响因子：
1.7
通讯作者：
L. Poggio;G. González;V. Confalonieri;C. Comas;C. Naranjo
中科院分区：
文献类型：
--
作者：
L. Poggio;G. González;V. Confalonieri;C. Comas;C. Naranjo
本文综述了我们在玉米属中的经典细胞遗传学和分子细胞遗传学研究。对玉米种和杂交种的减数分裂行为分析的结果证实了该属所有物种的双倍体性质，染色体的基本数目为x=5。所有2n=20的物种都是二倍化的异源四倍体，而泽兰(Z.perennis)(2n=40)是一个同源八倍体，有四个基因组，彼此之间略有分歧。这些分析还揭示了玉米种间存在合子后生殖隔离现象。我们利用基因组原位杂交(GISH)的研究为玉米及其近缘物种之间的进化关系提供了证据，并揭示了显著的基因组差异。特别是，以前被认为是密切相关的分类群之间的旋钮序列并不完全相同。我们的数据有力地表明，Tosinte Z.Mays parviglumis并不是栽培玉米的唯一祖先。三七在栽培玉米中的导入不能丢弃。
The present review summarizes our classical and molecular cytogenetic investigations in the genus Zea. The results obtained from the meiotic behavior analysis of Zea species and hybrids, confirm the amphiploid nature of all species in the genus, with a basic number of x = 5 chromosomes. All species with 2n = 20 are diploidized allotetraploids, whereas Z. perennis (2n = 40) is an allooctoploid with four genomes somewhat divergent from one another. These analyses also revealed the existence of postzygotic reproductive isolation among Zea species. Our studies using genomic in situ hybridization (GISH) provide evidence about the evolutionary relationships among maize and its allied species, and reveal remarkable genomic divergences. Particularly, knob sequences were not completely shared between taxa previously considered to be closely related. Our data strongly suggest that the teosinte Z. mays parviglumis is not the only progenitor of cultivated maize. Introgression of Tripsacum into cultivated maize cannot be discarded.