據(jù)11月20日的《科學(xué)》雜志報道說，玉米自交系B73的基因組序列測定是由Patrick Schnable及其同僚完成的,。這一序列測定應(yīng)該能夠幫助解答許多長期存在的疑問,，其中包括被稱作轉(zhuǎn)位因子的可移動DNA序列的影響以及現(xiàn)代玉米的基因組是如何從2個先祖基因組的融合演化而成的。 B73常常被用來繁殖新的飼用玉米系列，因此其基因組的測序應(yīng)該還能夠為人們提供基因標(biāo)記，幫助植物栽培者或種子公司開發(fā)細(xì)心打造的作物：例如,，這些作物可有更高的營養(yǎng)含量或需要較少的化肥。
研究人員發(fā)現(xiàn)并定位了超過3萬2000個基因,。他們確認(rèn),，該基因組中有近85%是由數(shù)百個轉(zhuǎn)位因子族所組成的。 這些因子影響著著絲點（即每條染色體的2個單體的連接點,，它們在細(xì)胞分裂中起著一種關(guān)鍵性的作用）的組成、大小和位置,。 文章的作者還描述了在基因組重復(fù)區(qū)域中的基因丟失為什么最可能是與該作物遠(yuǎn)古狀態(tài)時染色體拷貝數(shù)從4條減少至2條的原因,。
研究人員寫到：B37玉米系的序列“有可能會促進(jìn)基礎(chǔ)研究并推動人們在全球氣候變遷時期滿足全世界對食物、飼料,、能源及工業(yè)原料不斷增長的需求,。”（生物谷Bioon.com）
生物谷推薦原始出處：
Science 20 November 2009: DOI: 10.1126/science.1178534
The B73 Maize Genome: Complexity, Diversity, and Dynamics
We report an improved draft nucleotide sequence of the 2.3-gigabase genome of maize, an important crop plant and model for biological research. Over 32,000 genes were predicted, of which 99.8% were placed on reference chromosomes. Nearly 85% of the genome is composed of hundreds of families of transposable elements, dispersed nonuniformly across the genome. These were responsible for the capture and amplification of numerous gene fragments and affect the composition, sizes, and positions of centromeres. We also report on the correlation of methylation-poor regions with Mu transposon insertions and recombination, and copy number variants with insertions and/or deletions, as well as how uneven gene losses between duplicated regions were involved in returning an ancient allotetraploid to a genetically diploid state. These analyses inform and set the stage for further investigations to improve our understanding of the domestication and agricultural improvements of maize.
