SIZ1-Dependent Post-Translational Modification by SUMO Modulates Sugar Signaling and Metabolism in Arabidopsis thaliana

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Castro, PH (Author) Other; Verde, N (Author) Other; Lourenco, T (Author) Other; Magalhaes, AP (Author) Other; Tavares, RM (Author) Other; Rodriguez Bejarano, ER (Author) Other; Azevedo, H (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: PLANT AND CELL PHYSIOLOGY

Vol. 56

Pages: 2297-2311

ISSN: 0032-0781

Indexing

ISI Web of Knowledge - 38 Citations

Scopus - 37 Citations

Other information

Authenticus ID: P-00J-Z9Y

DOI: 10.1093/pcp/pcv149

Abstract (EN): Post-translational modification mechanisms function as switches that mediate the balance between optimum growth and the response to environmental stimuli, by regulating the activity of key proteins. SUMO (small ubiquitin-like modifier) attachment, or sumoylation, is a post-translational modification that is essential for the plant stress response, also modulating hormonal circuits to co-ordinate developmental processes. The Arabidopsis SUMO E3 ligase SAP and Miz 1 (SIZ1) is the major SUMO conjugation enhancer in response to stress, and is implicated in several aspects of plant development. Here we report that known SUMO targets are over-represented in multiple carbohydrate-related proteins, suggesting a functional link between sumoylation and sugar metabolism and signaling in plants. We subsequently observed that SUMO-conjugated proteins accumulate in response to high doses of sugar in a SIZ1-dependent manner, and that the null siz1 mutant displays increased expression of sucrose and starch catabolic genes and shows reduced starch levels. We demonstrated that SIZ1 controls germination time and post-germination growth via osmotic and sugar-dependent signaling, respectively. Glucose was specifically linked to SUMO-sugar interplay, with high levels inducing root growth inhibition and aberrant root hair morphology in siz1. The use of sugar analogs and sugar marker gene expression analysis allowed us to implicate SIZ1 in a signaling pathway dependent on glucose metabolism, probably involving modulation of SNF1-related kinase 1 (SnRK1) activity.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 15