Dataset Information

The control of endopolygalacturonase expression by the sugarcane RAV transcription factor during aerenchyma formation.

ABSTRACT: The development of lysigenous aerenchyma starts with cell expansion and degradation of pectin from the middle lamella, leading to cell wall modification, and culminating with cell separation. Here we report that nutritional starvation of sugarcane induced gene expression along sections of the first 5 cm of the root and between treatments. We selected two candidate genes: a RAV transcription factor, from the ethylene response factors superfamily, and an endopolygalacturonase (EPG), a glycosyl hydrolase related to homogalacturonan hydrolysis from the middle lamella. epg1 and rav1 transcriptional patterns suggest they are essential genes at the initial steps of pectin degradation during aerenchyma development in sugarcane. Due to the high complexity of the sugarcane genome, rav1 and epg1 were sequenced from 17 bacterial artificial chromosome clones containing hom(e)ologous genomic regions, and the sequences were compared with those of Sorghum bicolor. We used one hom(e)olog sequence from each gene for transactivation assays in tobacco. rav1 was shown to bind to the epg1 promoter, repressing ?-glucuronidase activity. RAV repression upon epg1 transcription is the first reported link between ethylene regulation and pectin hydrolysis during aerenchyma formation. Our findings may help to elucidate cell wall degradation in sugarcane and therefore contribute to second-generation bioethanol production.

SUBMITTER: Tavares EQP

PROVIDER: S-EPMC6322575 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The control of endopolygalacturonase expression by the sugarcane RAV transcription factor during aerenchyma formation.

Tavares Eveline Q P EQP De Souza Amanda P AP Romim Grayce H GH Grandis Adriana A Plasencia Anna A Gaiarsa Jonas W JW Grima-Pettenati Jacqueline J de Setta Nathalia N Van Sluys Marie-Anne MA Buckeridge Marcos S MS

Journal of experimental botany 20190101 2

The development of lysigenous aerenchyma starts with cell expansion and degradation of pectin from the middle lamella, leading to cell wall modification, and culminating with cell separation. Here we report that nutritional starvation of sugarcane induced gene expression along sections of the first 5 cm of the root and between treatments. We selected two candidate genes: a RAV transcription factor, from the ethylene response factors superfamily, and an endopolygalacturonase (EPG), a glycosyl hyd ...[more]

PMID: 30605523

Similar Datasets

Project description:Understanding plant adaptation mechanisms to prolonged water immersion provides options for genetic modification of existing crops to create cultivars more tolerant of periodic flooding. An important advancement in understanding flooding adaptation would be to elucidate mechanisms, such as aerenchyma air-space formation induced by hypoxic conditions, consistent with prolonged immersion. Lysigenous aerenchyma formation occurs through programmed cell death (PCD), which may entail the chemical modification of polysaccharides in root tissue cell walls. We investigated if a relationship exists between modification of pectic polysaccharides through de-methyl esterification (DME) and the formation of root aerenchyma in select Fabaceae species. To test this hypothesis, we first characterized the progression of aerenchyma formation within the vascular stele of three different legumes-Pisum sativum, Cicer arietinum, and Phaseolus coccineus-through traditional light microscopy histological staining and scanning electron microscopy. We assessed alterations in stele morphology, cavity dimensions, and cell wall chemistry. Then we conducted an immunolabeling protocol to detect specific degrees of DME among species during a 48-hour flooding time series. Additionally, we performed an enzymatic pretreatment to remove select cell wall polymers prior to immunolabeling for DME pectins. We were able to determine that all species possessed similar aerenchyma formation mechanisms that begin with degradation of root vascular stele metaxylem cells. Immunolabeling results demonstrated DME occurs prior to aerenchyma formation and prepares vascular tissues for the beginning of cavity formation in flooded roots. Furthermore, enzymatic pretreatment demonstrated that removal of cellulose and select hemicellulosic carbohydrates unmasks additional antigen binding sites for DME pectin antibodies. These results suggest that additional carbohydrate modification may be required to permit DME and subsequent enzyme activity to form aerenchyma. By providing a greater understanding of cell wall pectin remodeling among legume species, we encourage further investigation into the mechanism of carbohydrate modifications during aerenchyma formation and possible avenues for flood-tolerance improvement of legume crops.

Dataset Information

The control of endopolygalacturonase expression by the sugarcane RAV transcription factor during aerenchyma formation.

Publications

The control of endopolygalacturonase expression by the sugarcane RAV transcription factor during aerenchyma formation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets