@article{RN7,

title = {CYP707As are effectors of karrikin and strigolactone signalling pathways in Arabidopsis thaliana and parasitic plants},

author = {Guillaume Brun and Séverine Thoiron and Lukas Braem and Jean-Bernard Pouvreau and Grégory Montiel and Marc-Marie Lechat and Philippe Simier and Kris Gevaert and Sophie Goormachtig and Philippe Delavault},

url = {https://onlinelibrary.wiley.com/doi/10.1111/pce.13594},

doi = {10.1111/pce.13594},

issn = {0140-7791},

year  = {2019},

date = {2019-01-01},

urldate = {2019-01-01},

journal = {Plant Cell Environ},

volume = {42},

number = {9},

pages = {2612-2626},

abstract = {Karrikins stimulate Arabidopsis thaliana germination, whereas parasitic weeds of the Orobanchaceae family have evolved to respond to host-exuded compounds such as strigolactones, dehydrocostus lactone, and 2-phenylethyl isothiocyanate. In Phelipanche ramosa, strigolactone-induced germination was shown to require one of the CYP707A proteins involved in abscisic acid catabolism. Here, germination and gene expression were analysed to investigate the role of CYP707As in germination of both parasitic plants and Arabidopsis upon perception of germination stimulants, after using pharmacological inhibitors and Arabidopsis mutants disrupting germination signals. CYP707A genes were up-regulated upon treatment with effective germination stimulants in both parasitic plants and Arabidopsis. Obligate parasitic plants exhibited both intensified up-regulation of CYP707A genes and increased sensitivity to the CYP707A inhibitor abscinazole-E2B, whereas Arabidopsis cyp707a mutants still positively responded to germination stimulation. In Arabidopsis, CYP707A regulation required the canonical karrikin signalling pathway KAI2/MAX2/SMAX1 and the transcription factor WRKY33. Finally, CYP707As and WRKY33 also modulated Arabidopsis root architecture in response to the synthetic strigolactone rac-GR24, and wrky33-1 exhibited a shoot hyperbranched phenotype. This study suggests that the lack of host-independent germination in obligate parasites is associated with an exacerbated CYP707A induction and that CYP707As and WRKY33 are new players involved in a variety of strigolactone/karrikin responses.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{RN5,

title = {Seed germination in parasitic plants: what insights can we expect from strigolactone research?},

author = {Guillaume Brun and Lukas Braem and Séverine Thoiron and Kris Gevaert and Sophie Goormachtig and Philippe Delavault},

url = {https://watermark.silverchair.com/erx472.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAt4wggLaBgkqhkiG9w0BBwagggLLMIICxwIBADCCAsAGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQM1yniRk8_noMBOyNMAgEQgIICkQSx0NkVWTLILIUWSlmnkftHgPP-m5t-cQPJknvKituLwilM0lvjYzZ8hS9XgfOcZXtWI5s8xbpatlB8cdpZP9UIDbsBGHsUHt7S7HlpuAZMTQ45haVuNqJvyuKge5jMk7hS88X3g81iv7EI3sBpzHd2YIKMfNhaf48kbTwwrzS4DRYGNAvL4WBc-raLQpiuWzkwcigfD-aABZkBD1-gFe8IEUnOb2RkmjlUr_liOJU7PFy_Cx4vIQEP2JYFSTWPLCUjkUom_5WQQc6OEtCE9DM41tXRLSckgbL81--d43m9Fej8gsZ4BfyxtqW2HQeS-iOmIDEWFFSwij_htBntsNJyL2q_vklyiqNPmXnr7aAG5USvV7SKNyBXBLiZMhcK4LNAPAEXOmSdSzYuMfXoO0kbljSM6ht_Z5lxwGuDDEByCqSieqyirwwsSP5G7zjEwBgLyWku3qPSVQlSht3Zw5syxIR8XT1sWmvYDcKEttmpmlsNbJCFK8vfRSi8KeAAbs1zSzg17FzgpZCOkqRY5GKdESZfeVuNdyzEA5rlbuLLEKwV2LRm2RAg8b2ygsderPTNrSDDfwLwbN5VRWZF7lyhSHemRqDOnYU59ezeS882026E4kS2LpG_zwSjma0HyCHEE2GNywtVrwKfa_0_gKE1Q-OQ8INzeshP-lrHHZqa8Q4bZLCQXLfyE1qlJnLTroDX4UIpRRhA1Ildrf_lGv2vFlPxs9DzFqjLPoqsmb5cBVdv819hiJTgqzR4v-Nm2sw1H5Vp2V8l6aPIab9ijg3ZIlpm-B6VUnUsjZA5gxKdSDHHZzIQluh9wxsUc6c_WYBWNA20_EOSP9ALg-sQsplZk3VAb1WhQh7antobYSAx_A},

doi = {10.1093/jxb/erx472},

issn = {0022-0957},

year  = {2018},

date = {2018-01-01},

urldate = {2018-01-01},

journal = {J Exp Bot},

volume = {69},

number = {9},

pages = {2265-2280},

abstract = {Obligate root-parasitic plants belonging to the Orobanchaceae family are deadly pests for major crops all over the world. Because these heterotrophic plants severely damage their hosts even before emerging from the soil, there is an unequivocal need to design early and efficient methods for their control. The germination process of these species has probably undergone numerous selective pressure events in the course of evolution, in that the perception of host-derived molecules is a necessary condition for seeds to germinate. Although most of these molecules belong to the strigolactones, structurally different molecules have been identified. Since strigolactones are also classified as novel plant hormones that regulate several physiological processes other than germination, the use of autotrophic model plant species has allowed the identification of many actors involved in the strigolactone biosynthesis, perception, and signal transduction pathways. Nevertheless, many questions remain to be answered regarding the germination process of parasitic plants. For instance, how did parasitic plants evolve to germinate in response to a wide variety of molecules, while autotrophic plants do not? What particular features are associated with their lack of spontaneous germination? In this review, we attempt to illustrate to what extent conclusions from research into strigolactones could be applied to better understand the biology of parasitic plants.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{RN22,

title = {Seed response to strigolactone is controlled by abscisic acid-independent DNA methylation in the obligate root parasitic plant, Phelipanche ramosa L. Pomel},

author = {Marc-Marie Lechat and Guillaume Brun and Grégory Montiel and Christophe Véronési and Philippe Simier and Séverine Thoiron and Jean-Bernard Pouvreau and Philippe Delavault},

url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4449535/pdf/erv119.pdf},

doi = {10.1093/jxb/erv119},

issn = {0022-0957 (Print) 0022-0957},

year  = {2015},

date = {2015-01-01},

urldate = {2015-01-01},

journal = {J Exp Bot},

volume = {66},

number = {11},

pages = {3129-40},

abstract = {Seed dormancy release of the obligate root parasitic plant, Phelipanche ramosa, requires a minimum 4-day conditioning period followed by stimulation by host-derived germination stimulants, such as strigolactones. Germination is then mediated by germination stimulant-dependent activation of PrCYP707A1, an abscisic acid catabolic gene. The molecular mechanisms occurring during the conditioning period that silence PrCYP707A1 expression and regulate germination stimulant response are almost unknown. Here, global DNA methylation quantification associated with pharmacological approaches and cytosine methylation analysis of the PrCYP707A1 promoter were used to investigate the modulation and possible role of DNA methylation during the conditioning period and in the PrCYP707A1 response to GR24, a synthetic strigolactone analogue. Active global DNA demethylation occurs during the conditioning period and is required for PrCYP707A1 activation by GR24 and for subsequent seed germination. Treatment with 5-azacytidine, a DNA-hypomethylating molecule, reduces the length of the conditioning period. Conversely, hydroxyurea, a hypermethylating agent, inhibits PrCYP707A1 expression and seed germination. Methylated DNA immunoprecipitation followed by PCR experiments and bisulfite sequencing revealed that DNA demethylation particularly impacts a 78-nucleotide sequence in the PrCYP707A1 promoter. The results here demonstrate that the DNA methylation status during the conditioning period plays a crucial role independently of abscisic acid in the regulation of P. ramosa seed germination by controlling the strigolactone-dependent expression of PrCYP707A1.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}