Complex genetic interaction between glucose sensor HXK1 and E3 SUMO ligase SIZ1 in regulating plant morphogenesis

ABSTRACT

Sugar signaling forms the basis of metabolic activities crucial for an organism to perform essential life activities. In plants, sugars like glucose, mediate a wide range of physiological responses ranging from seed germination to cell senescence. This has led to the elucidation of cell signaling pathways involving glucose and its counterparts and the mechanism of how these sugars take control over major hormonal pathways such as auxin, ethylene, abscisic acid and cytokinin in Arabidopsis. Plants use HXK1(Hexokinase) as a glucose sensor to modulate changes in photosynthetic gene expression in response to high glucose levels. Other proteins such as SIZ1, a major SUMO E3 ligase have recently been implicated in controlling sugar responses via transcriptional and translational regulation of a wide array of sugar metabolic genes. Here, we show that these two genes work antagonistically and are epistatic in controlling responsiveness toward high glucose conditions.

KEYWORDS:

• Sugar signaling
• epistasis
• Hexokinase1
• post-germination growth arrest
• hypocotyl

Acknowledgements

SSR acknowledges Council of Scientific and Industrial Research (CSIR) and Fellowship from NIPGR. SS acknowledges Department of Biotechnology (DBT). AL acknowledges NIPGR core grant, DBT: NWBA-2015 (BT/HRD/NWBA/37/01/2015(xii)) and JC Bose fellowship 2021 (JCB/2021/000012). The authors are grateful to the DBT-eLibrary Consortium (DeLCON) for providing access to e-resources.

Disclosure statement

No potential conflict of interest was reported by the author(s).