Adaptomics of neofunctionalization: analysis of GORDITA-like genes in Brassicaceae
Project code: BE 2547/9-1
Arabis alpina, Brassica rapa, Cleome spinosa (Photographer: Amey Bhide).
Bsister genes are a group of genes with high sequence homology to the B class floral homeotic genes which specify petal and stamen identity. But unlike the B genes, Bsister genes are expressed in the carpel. Two Bsister genes exist in Arabidopsis thaliana, ARABIDOPSIS BSISTER (ABS) gene and GORDITA (GOA) a young, structurally and functionally deviant paralog of the ABS. A gene duplication event gave rise to the paralogous gene pair; while ABS retained the ancestral function, the GOA coding sequence and regulatory sequence changed significantly to acquire novel functions. Molecular analyses have shown that ABS and GOA have divergent expression patterns and non-redundant functions in seed coat development. Since the integrity and proper development of the seed coat is associated with seed germination, longevity etc. we will analyse if GOA plays a significant role in development and if it offers any adaptive advantages for the plant.
Within this project we will determine the exact time point of the ABS-GOA gene duplication event in a phylogenetic context to the Brassicales and analyze when and to which extent the expression patterns of these two genes diverged in different Brassicales lineages. We will identify putative orthologs and characterise their expression in selected Brassicales and Brassicaceae by promoter:GUS fusion assays and q RT-PCR. To characterize the function of these genes knock-out/knock-down lines will be generated and their phenotypes will be observed. ABS and GOA belong to the MADS group of transcription factors and form higher order complexes with different transcription factors to carry out their function. Yeast two-hybrid and BiFC assays will be carried with selected putative ABS and GOA orthologs to identify their protein interaction partners in different plant lineages.
The study of this closely related and yet highly diverged pair of genes will provide a unique insight into the molecular mechanisms involved in neo-functionalization after gene duplication.
ABS-GOA gene duplication
Publications related to the project
- Bhide A, Schliesky S, Reich M, Weber AP, Becker A. (2014) Analysis of the floral transcriptome of Tarenaya hassleriana (Cleomaceae), a member of the sister group to the Brassicaceae: towards understanding the base of morphological diversity in Brassicales. BMC Genomics. 2014 Feb 19;15:140.
- Cheng S1, van den Bergh E, Zeng P, Zhong X, Xu J, Liu X, Hofberger J, de Bruijn S, Bhide AS, Kuelahoglu C, Bian C, Chen J, Fan G, Kaufmann K, Hall JC, Becker A, Bräutigam A, Weber AP, Shi C, Zheng Z, Li W, Lv M, Tao Y, Wang J, Zou H, Quan Z, Hibberd JM, Zhang G, Zhu XG, Xu X, Schranz ME. (2013) The Tarenaya hassleriana genome provides insight into reproductive trait and genome evolution of crucifers. Plant Cell. 2013 Aug;25(8):2813-30.
- Yang X, Wu F, Du X, Chong K, Gramzow L, Schilling S, Becker A, Theißen G, Meng Z (2012) Live and let die - the Bsister MADS-box gene OsmADS29 controls the degeneration of cells in maternal tissues during seed development of rice (Oryza sativa). PLoS One. 2012;7(12):e51435.
- Erdmann R, Gramzow L, Melzer R, Theißen G, Becker A. (2010) GORDITA (AGL63) is a young paralog of the Arabidopsis thaliana Bsister MADS box gene ABS (TT16) that has undergone neofunctionalization. Plant Journal, 63: 914-924 .
- Becker A, Kaufmann K, Freialdenhoven A, Vincent C, Li MA, Saedler H, Theißen G. (2002) A novel MADS-box gene subfamily with a sistergroup relationship to class B floral homeotic genes. Mol. Gen. Gen. 266: 942-9504.
