Plants respond to hypoxia, often caused by submergence, by expressing a specific set of genes that contribute to acclimation to this unfavorable environmental condition. Genes induced by low oxygen include those encoding enzymes for carbohydrate metabolism and fermentation, pathways that are required for survival. Sugar availability is therefore of crucial importance for energy production under hypoxia. Here we show that Arabidopsis plants require starch for surviving submergence as well as for ensuring the rapid induction of genes encoding enzymes required for anaerobic metabolism. The starchless pgm mutant is highly susceptible to submergence and also fails to induce anaerobic genes at the level of the wild-type. Treating wild-type plants under conditions inducing sugar starvation results in a weak induction of alcohol dehydrogenase (ADH) and other anaerobic genes. Induction of gene expression under hypoxia requires transcription factors belonging to group VII Ethylene Responsive Factors (ERF-VII) that, together with Plant Cysteine Oxidases (PCOs) act as an oxygen sensing mechanism. We show that repression of this pathway by sugar starvation occurs downstream of the hypoxia-dependent stabilization of ERF-VII proteins and independently of the energy sensor protein kinases SnRK1.1 (SNF1-related kinase 1.1).
Gene regulation and survival under hypoxia requires starch availability and metabolism.
Loreti Elena;
2018
Abstract
Plants respond to hypoxia, often caused by submergence, by expressing a specific set of genes that contribute to acclimation to this unfavorable environmental condition. Genes induced by low oxygen include those encoding enzymes for carbohydrate metabolism and fermentation, pathways that are required for survival. Sugar availability is therefore of crucial importance for energy production under hypoxia. Here we show that Arabidopsis plants require starch for surviving submergence as well as for ensuring the rapid induction of genes encoding enzymes required for anaerobic metabolism. The starchless pgm mutant is highly susceptible to submergence and also fails to induce anaerobic genes at the level of the wild-type. Treating wild-type plants under conditions inducing sugar starvation results in a weak induction of alcohol dehydrogenase (ADH) and other anaerobic genes. Induction of gene expression under hypoxia requires transcription factors belonging to group VII Ethylene Responsive Factors (ERF-VII) that, together with Plant Cysteine Oxidases (PCOs) act as an oxygen sensing mechanism. We show that repression of this pathway by sugar starvation occurs downstream of the hypoxia-dependent stabilization of ERF-VII proteins and independently of the energy sensor protein kinases SnRK1.1 (SNF1-related kinase 1.1).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
