Transcriptional switch for programmed cell death in pith parenchyma of sorghum stems

Abstract

Significance Sugar and ethanol productivity from the sugar juice of grass stems depends on their water content. Pith parenchyma cells function as a water storage tissue in plant stems, and the death of these cells reduces stem water content. In this study, we identified a gene, long referred to as D , in a promising energy grass, Sorghum bicolor , that is responsible for reducing stem water content. D and its Arabidopsis ortholog encode master transcriptional switches that induce programmed death of stem pith parenchyma cells by activating autolytic enzymes. Identifying D as the gene involved in programmed death of plant pith parenchyma cells will provide an approach to breeding crops for sugar and ethanol production.