Muller's ratchet and drought stress adaptation in sexual and apomictic lineages of the Boechera holboellii complex (Brassicaceae)
Project code: SH 337/7-2
Natural high elevation growth habitat of sexual and apomictic Boechera in Colorado
We will test the evolutionary hypothesis that asexual plants are less adapted than sexual plants. This prediction is based on the model that apomictic (i.e. asexual) reproduction should be accompanied by a gradual accumulation of deleterious mutations (i.e. Muller's ratchet). We hypothesize that mutation accumulation in apomictic Boechera should lead to maladaptation in the wild, and we will measure the degree of maladaptation by examining DNA sequence variation in coding and promoter regions which are conserved throughout the Brassicaceae. Transplantation and growth chamber experiments will provide a phenotypic comparison of the degree of adaptation (or maladaptation) between sexual and apomictic Boechera, and we will finally examine whether maladaptation for drought response is manifested on gene expression levels by comparing expression patterns between sexual and apomictic Boechera, in loci whose upregulation is known to be beneficial in Brassica and Arabidopsis.
High-elevation growth plot for sexual and apomictic Boechera in Colorado (summer). Move your mouse over the image to see the winter-picture.
Publications related to the project
- Lovell JT, Williamson RJ, Wright SI, McKay JK, Sharbel TF (2017) Mutation accumulation in an asexual relative of Arabidopsis.
PLoS Genet. 2017 Jan 9;13(1):e1006550.
- Aliyu OM, Seifert M, Corral JM, Fuchs J, Sharbel TF. (2013) Copy number variation in transcriptionally active regions of sexual and apomictic Boechera demonstrates independently derived apomictic lineages.
Plant Cell. 2013 Oct;25(10):3808-23. - Corral JM, Vogel H, Aliyu OM, Hensel G, Thiel T, Kumlehn J, Sharbel TF. (2013) A conserved apomixis-specific polymorphism is correlated with exclusive exonuclease expression in premeiotic ovules of apomictic boechera species.
Plant Physiol. 2013 Dec;163(4):1660-72. - Mau M, Corral JM, Vogel H, Melzer M, Fuchs J, Kuhlmann M, de Storme N, Geelen D, Sharbel TF. (2013) The conserved chimeric transcript UPGRADE2 is associated with unreduced pollen formation and is exclusively found in apomictic Boechera species.
Plant Physiol. 2013 Dec;163(4):1640-59. - Lovell JT, Aliyu OM, Mau M, Schranz ME, Koch M, Kiefer C, Song BH, Mitchell-Olds T, Sharbel TF. (2013) On the origin and evolution of apomixis in Boechera.
Plant Reprod. 2013 Dec;26(4):309-15.
