Project description:In order to elucidate the role of the single Marchantia B-GATA ortholog in response to high light intensities, a transcriptomic analysis of Marchantia polymorpha BoGa, Mpb-gata1 mutants and MpB-GATA1ox under high-ligh stress conditions was performed.
Project description:Transcriptional profiling of Marchantia polymorpha Takaragaike-1 wild-type genotype, in samples from intact plants (NW, non-wounded) and from wounded plants, both in locally damaged tissue (W, wounded) and in systemic non-wounded tissues of the damaged plants (SD, systemic tissues of damaged plants)
Project description:Most of our current knowledge about the molecular events ruling plant-virus interaction come from studies focusing on vascular plants. We here characterized the molecular, cellular and physiological events goberning plant-virus interactions in the non-vascular liverwort Marchantia polymorpha.
Project description:In the present study, Marchantia polymorpha Mppcs loss of function mutants were generated through CRISPR/cas9 mediated genome-editing. To assess whether the knockout of MpPCS gene affects the transcription of M. polymorpha nuclear genes in unstressed condition, the Mppcs-2 knockout mutant and Cam2 wild-type transcriptomes were compared by RNA-Seq.
Project description:JAZ genes are negative regulators of jasmonate responses with a dual function as repressors of transcription factors and co-receptors, together with COI1, of the hormone jasmonoyl-isoleucine (JA-Ile). This family has been mainly studied in angiosperms, where high gene redundancy hinders the characterization of a complete depletion of JAZ function. Moreover, the recent discovery that JA-Ile is not the sole COI1/JAZ ligand in land plants, as dn-OPDA is the bioactive ligand in Marchantia polymorpha, underscores the importance of studying JAZ co-receptors in bryophytes. Here we exploited the low gene redundancy of the liverwort Marchantia polymorpha to characterize the function of the single MpJAZ in this early-divergent plant lineage. We demonstrate that MpJAZ is the ortholog of AtJAZ and acts as a repressor of dinor-OPDA responses in Marchantia. Mpjaz mutants show a dwarf phenotype and severe developmental defects related to growth inhibition, consistent with a constitutive activation of the dinor-OPDA pathway and the overaccumulation of both dinor-OPDA and its precursor OPDA. The expression of AtJAZ3 in Mpjaz complements MpJAZ repressor function, indicating that JAZ function is conserved across land plants. However, AtJAZ3 is unable to form co-receptor complexes with MpCOI1 and dn-OPDA, which evidences that the Jas domain, and not only COI1, determines ligand specificity.
Project description:The lipid-derived phytohormone jasmonoyl-isoleucine (JA-Ile) regulates plant immunity, growth and development in vascular plants by activating genome-wide transcriptional reprogramming. In Arabidopsis, this is largely orchestrated by the master regulator MYC2 and related transcription factors (TFs). However, the TFs activating this pathway in basal plant lineages are currently unknown. We report the functional conservation of MYC-related TFs between the eudicot Arabidopsis thaliana and the liverwort Marchantia polymorpha, a plant belonging to one of the most basal land-plants lineages. Phylogenetic analysis suggests that MYC function first appeared in charophycean algae, and therefore predates the evolutionary appearance of any other jasmonate pathway component. Marchantia possesses two functionally interchangeable MYC genes, one in females and one in males. Similar to AtMYC2, MpMYCs showed nuclear localization, interaction with JAZ-repressors, and regulation by light. Phenotypic and molecular characterization of loss- or gain-of-function mutants demonstrated that MpMYCs are necessary and sufficient for the activation of the pathway in Marchantia, but unlike their Arabidopsis orthologs, do not regulate fertility. Our results show that despite 450 million years of independent evolution, MYCs are functionally conserved between bryophytes and eudicots. Genetic conservation in one of the most basal lineages suggests that MYC function existed in the common ancestor of land plants and evolved from a pre-existing MYC function in charophycean algae.
Project description:Pattern-recognition receptor (PRR)-triggered immunity (PTI) plays a pivotal role in plant immunity to ward off a wide range of pathogenic microbes. The model liverwort Marchantia polymorpha is gaining popularity in investigating the evolution of plant-microbe interactions. The M. polymorpha is capable of triggering defense-related gene expression by sensing components in bacterial and fungal extracts, suggesting existence of PTI in this plant model. However, the molecular components that would form PTI in M. polymorpha have not yet been described. We show that, in M. polymorpha, lysin motif (LysM) receptor-like kinase (LYK) MpLYK1 and LYK-related (LYR) MpLYR, among four LysM receptor homologs, are required for sensing chitin and peptidoglycan (PGN) fragments and thereby triggering a series of immune responses. Phosphoproteomic analysis of M. polymorpha in response to chitin treatment comprehensively identified regulatory proteins that would shape LysM-mediated PTI. The identified proteins covered homologs of well-described PTI components in angiosperms as well as proteins whose roles in PTI are not yet determined including the blue-light receptor phototropin MpPHOT. We revealed that MpPHOT is required for a negative feedback of defense-related gene expression during PTI. Taken together, this study provides the basic framework of LysM-mediated PTI in M. polymorpha and demonstrates the utility of M. polymorpha as a plant model for discovering novel or fundamental molecular mechanisms underlying PRR-triggered immune signaling in plants.