RRC ID 36749
Author Undurraga SF, Press MO, Legendre M, Bujdoso N, Bale J, Wang H, Davis SJ, Verstrepen KJ, Queitsch C.
Title Background-dependent effects of polyglutamine variation in the Arabidopsis thaliana gene ELF3.
Journal Proc. Natl. Acad. Sci. U.S.A.
Abstract Tandem repeats (TRs) have extremely high mutation rates and are often considered to be neutrally evolving DNA. However, in coding regions, TR copy number mutations can significantly affect phenotype and may facilitate rapid adaptation to new environments. In several human genes, TR copy number mutations that expand polyglutamine (polyQ) tracts beyond a certain threshold cause incurable neurodegenerative diseases. PolyQ-containing proteins exist at a considerable frequency in eukaryotes, yet the phenotypic consequences of natural variation in polyQ tracts that are not associated with disease remain largely unknown. Here, we use Arabidopsis thaliana to dissect the phenotypic consequences of natural variation in the polyQ tract encoded by EARLY FLOWERING 3 (ELF3), a key developmental gene. Changing ELF3 polyQ tract length affected complex ELF3-dependent phenotypes in a striking and nonlinear manner. Some natural ELF3 polyQ variants phenocopied elf3 loss-of-function mutants in a common reference background, although they are functional in their native genetic backgrounds. To test the existence of background-specific modifiers, we compared the phenotypic effects of ELF3 polyQ variants between two divergent backgrounds, Col and Ws, and found dramatic differences. In fact, the Col-ELF3 allele, encoding the shortest known ELF3 polyQ tract, was haploinsufficient in Ws × Col F(1) hybrids. Our data support a model in which variable polyQ tracts drive adaptation to internal genetic environments.
Volume 109(47)
Pages 19363-7
Published 2012-11-20
DOI 10.1073/pnas.1211021109
PII 1211021109
PMID 23129635
PMC PMC3511081
MeSH Alleles Arabidopsis / genetics* Arabidopsis Proteins / genetics* Circadian Clocks / genetics Crosses, Genetic Genes, Plant / genetics* Haploinsufficiency / genetics Hybridization, Genetic Mutation / genetics* Peptides / genetics* Phenotype Tandem Repeat Sequences / genetics Transcription Factors / genetics*
IF 9.58
Times Cited 23
Arabidopsis / Cultured plant cells, genes pda09703