Moturu, Taraka Ramji; Thula, Sravankumar; Singh, Ravi Kumar; Nodzyński, Tomasz; Vařeková, Radka Svobodová; Friml, JiríISTA ; Simon, Sibu
Strigolactones (SLs) are a relatively recent addition to the list of plant hormones that control different aspects of plant development. SL signalling is perceived by an α/β hydrolase, DWARF 14 (D14). A close homolog of D14, KARRIKIN INSENSTIVE2 (KAI2), is involved in perception of an uncharacterized molecule called karrikin (KAR). Recent studies in Arabidopsis identified the SUPPRESSOR OF MAX2 1 (SMAX1) and SMAX1-LIKE 7 (SMXL7) to be potential SCF–MAX2 complex-mediated proteasome targets of KAI2 and D14, respectively. Genetic studies on SMXL7 and SMAX1 demonstrated distinct developmental roles for each, but very little is known about these repressors in terms of their sequence features. In this study, we performed an extensive comparative analysis of SMXLs and determined their phylogenetic and evolutionary history in the plant lineage. Our results show that SMXL family members can be sub-divided into four distinct phylogenetic clades/classes, with an ancient SMAX1. Further, we identified the clade-specific motifs that have evolved and that might act as determinants of SL-KAR signalling specificity. These specificities resulted from functional diversities among the clades. Our results suggest that a gradual co-evolution of SMXL members with their upstream receptors D14/KAI2 provided an increased specificity to both the SL perception and response in land plants.
Journal of Experimental Botany
This project received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Actions and it is co-financed by the South Moravian Region under grant agreement No. 665860 (SS). Access to computing and storage facilities owned by parties and projects contributing to the national grid infrastructure, MetaCentrum, provided under the program ‘Projects of Large Infrastructure for Research, Development, and Innovations’ (LM2010005) was greatly appreciated (RSV). The project was funded by The Ministry of Education, Youth and Sports/MES of the Czech Republic under the project CEITEC 2020 (LQ1601) (TN, TRM). JF was supported by the European Research Council (project ERC-2011-StG 20101109-PSDP) and the Czech Science Foundation GAČR (GA13-40637S). We thank Dr Kamel Chibani for active discussions on the evolutionary analysis and Nandan Mysore Vardarajan for his critical comments on the manuscript. This article reflects only the authors’ views, and the EU is not responsible for any use that may be made of the information it contains.
Moturu TR, Thula S, Singh RK, et al. Molecular evolution and diversification of the SMXL gene family. Journal of Experimental Botany. 2018;69(9):2367-2378. doi:10.1093/jxb/ery097
Moturu, T. R., Thula, S., Singh, R. K., Nodzyński, T., Vařeková, R. S., Friml, J., & Simon, S. (2018). Molecular evolution and diversification of the SMXL gene family. Journal of Experimental Botany. Oxford University Press. https://doi.org/10.1093/jxb/ery097
Moturu, Taraka Ramji, Sravankumar Thula, Ravi Kumar Singh, Tomasz Nodzyński, Radka Svobodová Vařeková, Jiří Friml, and Sibu Simon. “Molecular Evolution and Diversification of the SMXL Gene Family.” Journal of Experimental Botany. Oxford University Press, 2018. https://doi.org/10.1093/jxb/ery097.
T. R. Moturu et al., “Molecular evolution and diversification of the SMXL gene family,” Journal of Experimental Botany, vol. 69, no. 9. Oxford University Press, pp. 2367–2378, 2018.
Moturu TR, Thula S, Singh RK, Nodzyński T, Vařeková RS, Friml J, Simon S. 2018. Molecular evolution and diversification of the SMXL gene family. Journal of Experimental Botany. 69(9), 2367–2378.
Moturu, Taraka Ramji, et al. “Molecular Evolution and Diversification of the SMXL Gene Family.” Journal of Experimental Botany, vol. 69, no. 9, Oxford University Press, 2018, pp. 2367–78, doi:10.1093/jxb/ery097.