Transcriptional alterations during proliferation and lignification in Phyllostachys nigra cells

Abstract

Highly-lignified culms of bamboo show distinctive anatomical and mechanical properties compared with the culms of other grass species. A cell culture system for Phyllostachys nigra has enabled investigating the alterations in cellular states associated with secondary cell wall formation during its proliferation and lignification in woody bamboos. To reveal transcriptional changes related to lignification in bamboo, we analyzed transcriptome in P. nigra cells treated with the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D) and the synthetic cytokinin benzylaminopurine (BA) by RNA-seq analysis. We found that some genes putatively involved in cell wall biogenesis and cell division were up-regulated in response to the 2,4-D treatment, and the induction of lignification by the BA treatment was correlated with up-regulation of genes involved in the shikimate pathway. We also found that genes encoding MYB transcription factors (TFs) show correlated expression patterns with those encoding cinnamyl alcohol dehydrogenase (CAD), suggesting that MYB TFs presumably regulate secondary cell wall formation in the bamboo cells. These findings suggest that cytokinin signaling may regulate lignification in P. nigra cells through coordinated transcriptional regulation and metabolic alterations. Our results have also produced a useful resource for better understanding of secondary cell wall formation in bamboo plants.

Establishment of Pluripotent Cell Cultures to Explore Allelopathic Activity of Coffee Cells by Protoplast Co-Culture Bioassay Method

“…In glossaries, for example [ 7 ], stem cell developmental potency is classified into several types: unipotent, a stem cell able to develop into only one cell or tissue type; multipotent, a stem cell able to develop into more than one cell type of the plant body; pluripotent, a stem cell able to develop into most, but not all, cell types that constitute the body; and totipotent, a stem cell able to develop into all cell types. These are reflected by case studies that use various cell and tissue culture methodologies, such as callus culture, tracheary element formation, adventitious bud/root formation, and somatic embryogenesis [ 8 , 9 , 10 , 11 ]. However, to date, there are no definite and highly efficient standards for the regulation of stem cell development in in vitro plant cell and tissue cultures.…”

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“…Only four CesA genes were upregulated exclusively in induced samples (at the transition from 0 to 12 h), but none of them are potential homologs to rice secondary wall CesAs ( Supplementary Table S7). Similar results were found for a xylogenic culture of the woody bamboo species Phyllostachys nigra, in which SCW-related CesAs were not upregulated upon inducing conditions (Ogita et al, 2018). Noteworthy, the determination of CesAs specificities in primary or secondary wall deposition in sugarcane has been problematic.…”

Differentiation of Tracheary Elements in Sugarcane Suspension Cells Involves Changes in Secondary Wall Deposition and Extensive Transcriptional Reprogramming

“…The identification of WRKYs from different groups within the family with a role in regulating the NAC-MYB network in different cell types indicates that there is still much to be explored in terms of regulation of SCW deposition. For instance, TFs from the GRAS family are interesting candidates for further analysis, as these TFs have been systematically found as co-expressed with SCW biosynthetic genes in different species, such as Arabidopsis (Rao et al, 2019), bamboo (Ogita et al, 2018), switchgrass (Rao et al, 2017(Rao et al, , 2019, and Miscanthus (Hu et al, 2017), and were also found in the sugarcane network ( Figure 7A).…”

“…After induction, changes in cell morphology, cell wall composition and structure, and transcript and metabolite abundances can be investigated by harvesting differentiating cells at different time points (Devillard and Walter, 2014). Xylogenic cultures have been successfully employed to unravel and characterize developmental processes associated with xylogenesis, such as xylem differentiation, SCW deposition and programmed cell death in different plant species (Kubo et al, 2005;Yamagishi et al, 2013;Devillard and Walter, 2014;Ogita et al, 2018). Here, we report on the establishment of a xylogenic culture as a model system to study SCW deposition in sugarcane.…”