生物谷报道:美国科学家发现了一个基因突变使得西红柿的体积比它的野生祖先膨胀了1000倍。
研究人员称,这个变化结果是由一个短DNA序列插入造成的,该序列插入到一个能够控制西红柿中隔膜数量的基因中间。这种插入使得隔膜的数量大大增加,加上之前鉴别出的一个能够促进细胞分裂的基因突变,最终使西红柿的体积变大。这两种变化是最近才发生的,并且由于人们喜欢又大又多汁的西红柿而保存了下来。研究结果刊载在5月8日的《自然—遗传学》上。(生物谷www.bioon.con)
生物谷推荐原始出处:
Nature Genetics,doi:10.1038/ng.144,Bin Cong, Luz S Barrero & Steven D Tanksley
Regulatory change in YABBY-like transcription factor led to evolution of extreme fruit size during tomato domestication
Bin Cong1,2, Luz S Barrero1,2,3 & Steven D Tanksley1,2
Plant domestication represents an accelerated form of evolution, resulting in exaggerated changes in the tissues and organs of greatest interest to humans (for example, seeds, roots and tubers). One of the most extreme cases has been the evolution of tomato fruit. Cultivated tomato plants produce fruit as much as 1,000 times larger than those of their wild progenitors. Quantitative trait mapping studies have shown that a relatively small number of genes were involved in this dramatic transition, and these genes control two processes: cell cycle and organ number determination1. The key gene in the first process has been isolated and corresponds to fw2.2, a negative regulator of cell division2, 3. However, until now, nothing was known about the molecular basis of the second process. Here, we show that the second major step in the evolution of extreme fruit size was the result of a regulatory change of a YABBY-like transcription factor (fasciated) that controls carpel number during flower and/or fruit development.
Department of Plant Breeding and Genetics, Cornell University, Ithaca, New York 14853, USA.
Department of Plant Biology, Cornell University, Ithaca, New York 14853, USA.
Present address: Corporación Colombiana de Investigación Agropecuaria, Bogotá, Colombia.