The model land plant Physcomitrella patens synthesizes flavonoids which may act as protectant of ultraviolet-B radiation. We aimed to uncover its flavonoid profile, for which metabolome analysis using liquid chromatography coupled with Ion trap/Orbitrap mass spectrometry was performed. From the 80% methanol extracts, 661 valid peaks were detected. Prediction of the elemental compositions within a mass accuracy of 2 ppm indicated that 217 peaks had single elemental composition. A compound database search revealed 47 peaks to be annotated as secondary metabolites based on the compound database search. Comprehensive substituent search by ShiftedIonsFinder showed there were 13 peaks of potential flavonoid derivatives. Interestingly, a peak having m/z 287.0551, corresponding to that of luteolin, was detected, even though flavone synthase has never been identified in P. patens. Using P. patens labeled with stable isotopes (13C-, 15N-, 18O-, and 34S), we confirmed the elemental composition of the peak as C15H10O6. By a comparison of MS/MS spectra with that of authentic standard, the peak was identified as luteolin or related flavone isomers. This is the first report of luteolin or related flavones synthesis and the possibility of the existence of an unknown enzyme with flavone synthase activity in P. patens.The shoot apical meristem (SAM) is typically divided into three cell layers the outermost epidermal layer (L1), the subepidermal layer (L2) and the inner corpus region (L3). Structures within the cell layers are normally maintained throughout development; however, through vegetative propagation of a periclinal chimeric chrysanthemum expressing a fluorescent protein gene only in the L1 layer, we collected twelve independent shoots that had partially mosaic fluorescent inner cells (L2, L3) in addition to fluorescent epidermal cells (L1). Furthermore, the elongated tissues of nine shoots out of the twelve had no internal fluorescent cells, i.e., they had the original L1 chimerism. Observations of the fluorescence distribution suggested that the change in chimerism occurred at the nodes, indicating previously unnoticed cell layer dynamics occurring at the nodes.Ligation-independent cloning (LIC), such as Gibson Assembly, tends to produce clones without an insert, depending on the sequences present at the ends of linearized vectors. We used a nicking enzyme-mediated LIC (NE-LIC) method to construct a cDNA library in a binary vector pER8. Prior to constructing the cDNA library, pilot experiments were carried out, in which the GUS coding sequence was cloned into pER8 using NE-LIC. Approximately 12% of input vector DNAs were converted to plasmids carrying a GUS insert, and no plasmids without an insert were detected, indicating that this strategy is highly effective for cloning with the binary vector pER8. Therefore, NE-LIC was adopted to construct a cDNA library in pER8, by using cDNA that was PCR-amplified from a library constructed in another vector. As a result, a cDNA library in pER8 was successfully constructed. During library construction, it is important to exclude plasmids without an insert, since contamination from plasmids without inserts decreases the efficiency of screening. Therefore, NE-LIC is useful for the construction of cDNA libraries.Phosphatidic acid plays an important role in plant immune responses against phytopathogenic bacteria in Nicotiana benthamiana. Here we focused on phosphoinositide dependent protein kinases (PDKs) as a candidate required for phosphatidic acid signaling. Based on Arabidopsis PDK sequences, we identified four putative PDK orthologs in N. benthamiana genome. To address the role of PDKs in plant defense responses, we created all four NbPDKs-silenced plants by virus-induced gene silencing. the NbPDKs-silenced plants showed a moderately reduced growth phenotype. Induction of hypersensitive cell death was compromised in the NbPDKs-silenced plants challenged with Ralstonia solanacearum. The hypersensitive cell death induced by bacterial effectors was also reduced in the NbPDKs-silenced plants. the NbPDKs-silenced plants showed decreased production of salicylic acid, jasmonic acid and jasmonoyl-L-isoleucine, as well as hydrogen peroxide after inoculation with R. solanacearum. These results suggest that NbPDKs might have an important role in the regulation of the hypersensitive cell death via plant hormone signaling and oxidative burst.Receptor complex formation at the cell surface is a key step to initiate downstream signaling but the contribution of this process for the regulation of the direction of downstream responses is not well understood. In the plant-microbe interactions, while CERK1, an Arabidopsis LysM-RLK, mediates chitin-induced immune responses, NFR1, a Lotus homolog of CERK1, regulates the symbiotic process with rhizobial bacteria through the recognition of Nod factors. Concerning the mechanistic insight of the regulation of such apparently opposite biological responses by the structurally related RLKs, Nakagawa et al. previously showed that the addition of YAQ sequence, conserved in NFR1 and other symbiotic LysM-RLKs, to the kinase domain of CERK1 switched downstream responses from defense to symbiosis using a set of chimeric receptors, NFR1-CERK1s. These results indicated that such a subtle difference in the cytoplasmic domain of LysM-RLKs could determine the direction of host responses from defense to symbiosis. On the other hand, it is still not understood how such structural differences in the cytoplasmic domains determine the direction of host responses. We here analyzed the interaction between chimeric NFR1s and NFR5, a partner receptor of NFR1, by co-immunoprecipitation (Co-IP) of these proteins transiently expressed in Nicotiana benthamiana. These results indicated that the cytoplasmic interaction between the LysM-RLKs is important for the symbiotic receptor complex formation and the YAQ containing region of NFR1 contributes to trigger symbiotic signaling through the successful formation of NFR1/NFR5 complex.Natural seed germination is difficult to achieve in numerous plant species of wide economic importance. The germination of Polygonatum macranthum seeds takes as long as one and a half years under natural conditions. In addition, propagation by rhizome is also extremely slow in this species. Therefore, the natural propagation of P. macranthum through seeds or rhizome is not efficient. In this study, an efficient in vitro propagation system for P. macranthum from immature seeds with seed coat was developed, using a new surface sterilization protocol that utilized a low concentration of hypochlorite. In vitro germination was achieved at a rate of 30% within 9 weeks after inoculation on 1/2 MS medium. Shoot explants from seedlings were successfully cultured on 1/2 MS medium. learn more Supplementation of the 1/2 MS medium with cytokinin 6-benzylaminopurine (BAP) facilitated efficient propagation by microrhizome. An efficient propagation rate of 1.3 microrhizomes per shoot in an 8-week culture period could be achieved by using a concentration of 1 mg l-1 BAP.