Journal Article

Morphological dissection and cellular and transcriptome characterizations of bamboo pith cavity formation reveal a pivotal role of genes related to programmed cell death

Sun, Xuepeng, Jiao, Chen, Cui, Dingfan, Wang, Yujun, Feng, Xingyu, Wei, Qiang, Ding, Yulong, Li, Zhongru, Zhang, Chunxia, Guo, Lin, Fei, Zhangjun, Feng, Jianyuan

2019

Overview

Summary Pith cavity formation is critical for bamboo to overcome the bending force during its fast growth; however, the underlying molecular mechanisms remain largely unknown. Multiple approaches, including anatomical dissection, mathematical modelling and transcriptome profiling, were employed in this study to investigate the biology of pith cavity formation in bamboo Pseudosasa japonica. We found that the corruption of pith tissue occurred sequentially and asymmetrically from the top‐centre of the internode down to the bottom, which might be caused by the combined effects of asymmetrical radial and axial tensile forces during shoot‐wall cell elongation and spiral growth of bamboo internodes. Programmed cell death (PCD) in pitch manifested by TUNEL positive nuclei, DNA cleavage and degraded organelles, and potentially regulated by ethylene and calcium signalling pathway, ROS burst, cell wall modification, proteolysis and nutrient recycle genes, might be responsible for pith tissue corruption of Ps. japonica. Although similar physiological changes and transcriptome profiles were found in different bamboo species, different formation rates of pith cavity were observed, which might be caused by different pith cells across the internode that were negatively correlated with the culm diameter. These findings provided a systematical view on the formation of bamboo pith cavity and revealed that PCD plays an important role in the bamboo pith cavity formation.

• Publisher: John Wiley & Sons, Inc,John Wiley and Sons Inc
• Subject: Apoptosis / Apoptosis - genetics / asymmetrical growth / Asymmetry / Axial stress / Bamboo / bamboos / Biochemistry / biotechnology / calcium / Calcium signalling / Cell death / cell growth / Cell walls / Corruption / culms / Deoxyribonucleic acid / Dissection / DNA / DNA Cleavage / DNA damage / Elongation / ethylene / fast growth / Gene expression / Gene Expression Profiling / Genes / Genes, Plant - genetics / Genes, Plant - physiology / Genetic research / In Situ Nick-End Labeling / Investigations / Mathematical models / Microscopy, Electron, Transmission / Molecular modelling / Morphology / Organelles / Physiology / pith / pith cavity / Poaceae - anatomy & histology / Poaceae - genetics / Poaceae - growth & development / Poaceae - metabolism / programmed cell death / Proteolysis / Pseudosasa / reactive oxygen species / RNA, Plant - metabolism / Signal transduction / Surgery / transcriptome / Transcriptome - genetics / Transcriptome - physiology / Transmission electron microscopy