A Single Nucleotide Deletion in Gibberellin20-oxidase1 Causes Alpine Dwarfism in Arabidopsis.

Abstract

Alpine dwarfism is widely observed in alpine plant populations and often considered a high-altitude adaptation, yet its molecular basis and ecological relevance remain unclear. In this study, we used map-based cloning and field transplant experiments to investigate dwarfism in natural Arabidopsis (Arabidopsis thaliana) accessions collected from the Swiss Alps. A loss-of-function mutation due to a single nucleotide deletion in gibberellin20-oxidase1 (GA5) was identified as the cause of dwarfism in an alpine accession. The mutated allele, ga5-184, was found in two natural Arabidopsis populations collected from one geographic region at high altitude, but was different from all other reported ga5 null alleles, suggesting that this allele has evolved locally. In field transplant experiments, the dwarf accession with ga5-184 exhibited a fitness pattern consistent with adaptation to high altitude. Across a wider array of accessions from the Swiss Alps, plant height decreased with altitude of origin, but fitness patterns in the transplant experiments were variable and general altitudinal adaptation was not evident. In general, our study provides new insights into molecular basis and possible ecological roles of alpine dwarfism, and demonstrates the importance of the GA-signaling pathway for the generation of ecologically relevant variation in higher plants.

• Authors: Yonghai Luo, Xinwei Dong, Tianying Yu, Xuan Shi, Zongyun Li, Weicai Yang, Alex Widmer, Sophie Karrenberg
• Journal: Plant physiology (Plant Physiol) Vol. 168 Issue 3 Pg. 930-7 (Jul 2015) ISSN: 1532-2548 [Electronic] United States
• PMID: 25941313 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 American Society of Plant Biologists. All Rights Reserved.

Chemical References

• Arabidopsis Proteins
• Nucleotides
• Mixed Function Oxygenases
• gibberellin 20 oxidase 1, Arabidopsis
• gibberellin, 2-oxoglutarate-oxygen oxidoreductase (20-hydroxylating, oxidizing)

Topics

• Altitude
• Amino Acid Sequence
• Analysis of Variance
• Arabidopsis (anatomy & histology, enzymology, genetics)
• Arabidopsis Proteins (chemistry, genetics)
• Base Sequence
• Cloning, Molecular
• Ecosystem
• Ecotype
• Genes, Plant
• Mixed Function Oxygenases (chemistry, genetics)
• Models, Biological
• Molecular Sequence Data
• Mutation (genetics)
• Nucleotides (genetics)
• Reproducibility of Results
• Seeds (anatomy & histology)