植物中去除非必需或表达较少的 DNA 的机制的分馏诱变及其类似后果。

Fractionation mutagenesis and similar consequences of mechanisms removing dispensable or less-expressed DNA in plants.

机构信息

Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA.

出版信息

Curr Opin Plant Biol. 2012 Apr;15(2):131-9. doi: 10.1016/j.pbi.2012.01.015. Epub 2012 Feb 14.

DOI:10.1016/j.pbi.2012.01.015

Abstract

Unlike in mammals, plants rapidly delete functionless, nonrepetitive DNA from their genomes. Following paleopolyploidies, duplicate genes are deleted by intrachromosomal recombination. This may explain how flowering plants have survived multiple whole genome duplications. Genes are disproportionately lost from one parental subgenome, the subgenome that is less expressed in the polyploid. The origin of this unbalanced expression between genomes remains unknown. The consequences of the tradeoffs between transposon repression and gene expression represent one potential explanation of genome dominance. If so, the same mechanisms may act in heterosis: genome dominance is like inbreeding depression. Regulatory DNA deletion following polyploidy combined with abundant RNA-seq expression datasets are being used to generate testable hypothesizes regarding the function of specific cis-regulatory sequences.

摘要

与哺乳动物不同，植物会从其基因组中快速删除无功能、非重复的 DNA。在古多倍体事件之后，重复基因通过染色体内重组被删除。这可能解释了开花植物如何在多次全基因组加倍中幸存下来。基因从一个亲本亚基因组中不成比例地丢失，这个亚基因组在多倍体中表达较少。这种基因组间表达不平衡的起源仍然未知。转座子抑制和基因表达之间的权衡所带来的后果代表了对基因组优势的一个潜在解释。如果是这样，那么相同的机制可能在杂种优势中起作用：基因组优势类似于自交衰退。多倍体后结合丰富的 RNA-seq 表达数据集的调控 DNA 删除，正在被用来生成关于特定顺式调控序列功能的可测试假说。