Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovation
Abstract Background Strigolactones (SLs) are an important class of carotenoid-derived signalling molecule in plants, which function both as exogenous signals in the rhizosphere and as endogenous plant hormones. In flowering plants, SLs are synthesized by a core pathway of four enzymes and are percei...
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| Format: | Article |
| Language: | English |
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BMC
2019-09-01
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| Series: | BMC Biology |
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| Online Access: | http://link.springer.com/article/10.1186/s12915-019-0689-6 |
| _version_ | 1818289870464876544 |
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| author | Catriona H. Walker Karen Siu-Ting Alysha Taylor Mary J. O’Connell Tom Bennett |
| author_facet | Catriona H. Walker Karen Siu-Ting Alysha Taylor Mary J. O’Connell Tom Bennett |
| author_sort | Catriona H. Walker |
| collection | DOAJ |
| description | Abstract Background Strigolactones (SLs) are an important class of carotenoid-derived signalling molecule in plants, which function both as exogenous signals in the rhizosphere and as endogenous plant hormones. In flowering plants, SLs are synthesized by a core pathway of four enzymes and are perceived by the DWARF14 (D14) receptor, leading to degradation of SMAX1-LIKE7 (SMXL7) target proteins in a manner dependent on the SCFMAX2 ubiquitin ligase. The evolutionary history of SLs is poorly understood, and it is not clear whether SL synthesis and signalling are present in all land plant lineages, nor when these traits evolved. Results We have utilized recently-generated genomic and transcriptomic sequences from across the land plant clade to resolve the origin of each known component of SL synthesis and signalling. We show that all enzymes in the core SL synthesis pathway originated at or before the base of land plants, consistent with the previously observed distribution of SLs themselves in land plant lineages. We also show that the late-acting enzyme LATERAL BRANCHING OXIDOREDUCTASE (LBO) may be considerably more ancient than previously thought. We perform a detailed phylogenetic analysis of SMXL proteins and show that specific SL target proteins only arose in flowering plants. We also assess diversity and protein structure in the SMXL family, identifying several previously unknown clades. Conclusions Overall, our results suggest that SL synthesis is much more ancient than canonical SL signalling, consistent with the idea that SLs first evolved as rhizosphere signals and were only recruited much later as hormonal signals. |
| first_indexed | 2024-12-13T02:19:09Z |
| format | Article |
| id | doaj.art-3505ad8a3a544598acc5b65906e89ce3 |
| institution | Directory Open Access Journal |
| issn | 1741-7007 |
| language | English |
| last_indexed | 2024-12-13T02:19:09Z |
| publishDate | 2019-09-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Biology |
| spelling | doaj.art-3505ad8a3a544598acc5b65906e89ce32022-12-22T00:02:49ZengBMCBMC Biology1741-70072019-09-0117111910.1186/s12915-019-0689-6Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovationCatriona H. Walker0Karen Siu-Ting1Alysha Taylor2Mary J. O’Connell3Tom Bennett4School of Biology, Faculty of Biological Sciences, University of LeedsInstitute for Global Food Security, School of Biological Sciences, Queens UniversityComputational and Molecular Evolutionary Biology Research Group, School of Biology, Faculty of Biological Sciences, University of LeedsComputational and Molecular Evolutionary Biology Research Group, School of Biology, Faculty of Biological Sciences, University of LeedsSchool of Biology, Faculty of Biological Sciences, University of LeedsAbstract Background Strigolactones (SLs) are an important class of carotenoid-derived signalling molecule in plants, which function both as exogenous signals in the rhizosphere and as endogenous plant hormones. In flowering plants, SLs are synthesized by a core pathway of four enzymes and are perceived by the DWARF14 (D14) receptor, leading to degradation of SMAX1-LIKE7 (SMXL7) target proteins in a manner dependent on the SCFMAX2 ubiquitin ligase. The evolutionary history of SLs is poorly understood, and it is not clear whether SL synthesis and signalling are present in all land plant lineages, nor when these traits evolved. Results We have utilized recently-generated genomic and transcriptomic sequences from across the land plant clade to resolve the origin of each known component of SL synthesis and signalling. We show that all enzymes in the core SL synthesis pathway originated at or before the base of land plants, consistent with the previously observed distribution of SLs themselves in land plant lineages. We also show that the late-acting enzyme LATERAL BRANCHING OXIDOREDUCTASE (LBO) may be considerably more ancient than previously thought. We perform a detailed phylogenetic analysis of SMXL proteins and show that specific SL target proteins only arose in flowering plants. We also assess diversity and protein structure in the SMXL family, identifying several previously unknown clades. Conclusions Overall, our results suggest that SL synthesis is much more ancient than canonical SL signalling, consistent with the idea that SLs first evolved as rhizosphere signals and were only recruited much later as hormonal signals.http://link.springer.com/article/10.1186/s12915-019-0689-6StrigolactonesStrigolactone synthesisStrigolactone signallingPhylogenetics |
| spellingShingle | Catriona H. Walker Karen Siu-Ting Alysha Taylor Mary J. O’Connell Tom Bennett Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovation BMC Biology Strigolactones Strigolactone synthesis Strigolactone signalling Phylogenetics |
| title | Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovation |
| title_full | Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovation |
| title_fullStr | Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovation |
| title_full_unstemmed | Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovation |
| title_short | Strigolactone synthesis is ancestral in land plants, but canonical strigolactone signalling is a flowering plant innovation |
| title_sort | strigolactone synthesis is ancestral in land plants but canonical strigolactone signalling is a flowering plant innovation |
| topic | Strigolactones Strigolactone synthesis Strigolactone signalling Phylogenetics |
| url | http://link.springer.com/article/10.1186/s12915-019-0689-6 |
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