Regenerant arabidopsis lineages display a distinct genome-wide spectrum of mutations conferring variant phenotypes
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Jiang, CaifuMithani, Aziz
Gan, Xiangchao
Belfield, Eric J.
Klingler, John P.
Zhu, Jian-Kang
Ragoussis, Jiannis
Mott, Richard
Harberd, Nicholas P.
KAUST Department
Plant Stress Genomics Research LabDate
2011-07-28Permanent link to this record
http://hdl.handle.net/10754/334570Metadata
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Multicellular organisms can be regenerated from totipotent differentiated somatic cell or nuclear founders [1-3]. Organisms regenerated from clonally related isogenic founders might a priori have been expected to be phenotypically invariant. However, clonal regenerant animals display variant phenotypes caused by defective epigenetic reprogramming of gene expression [2], and clonal regenerant plants exhibit poorly understood heritable phenotypic ("somaclonal") variation [4-7]. Here we show that somaclonal variation in regenerant Arabidopsis lineages is associated with genome-wide elevation in DNA sequence mutation rate. We also show that regenerant mutations comprise a distinctive molecular spectrum of base substitutions, insertions, and deletions that probably results from decreased DNA repair fidelity. Finally, we show that while regenerant base substitutions are a likely major genetic cause of the somaclonal variation of regenerant Arabidopsis lineages, transposon movement is unlikely to contribute substantially to that variation. We conclude that the phenotypic variation of regenerant plants, unlike that of regenerant animals, is substantially due to DNA sequence mutation. 2011 Elsevier Ltd. All rights reserved.Citation
Jiang C, Mithani A, Gan X, Belfield EJ, Klingler JP, et al. (2011) Regenerant Arabidopsis Lineages Display a Distinct Genome-Wide Spectrum of Mutations Conferring Variant Phenotypes. Current Biology 21: 1385-1390. doi:10.1016/j.cub.2011.07.002.Publisher
Elsevier BVJournal
Current BiologyISSN
09609822PubMed ID
21802297PubMed Central ID
PMC3162137Scopus Count
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