Assistant Professor, Shahjalal University of Science and Technology, Sylhet, BANGLADESH

Friday 11 June 2021 | 3:00 pm – ICGEB New Delhi, INDIA

Arabidopsis Snf1-related protein kinase 1 (SnRK1): Subunit localization, Composition, and regulation

Hosts: D. Salunke

SnRK1 plays a pivotal role in monitoring and coordination of energy homeostasis, carbon metabolism, stress responses, cell growth and viability. We have labbelled Arabidopsis SnRK1 subunits with fluorescent protein tags by recombineering, analyze their cellular co-localization and affinity purify protein complexes of individual subunits. Comparative mass spectrometry analysis indicates dimerization of SnRK1α kinases AKIN10 and AKIN11, excludes the occurrence of multiple β-subunits in common complexes, and identifies class II TREHALOSE-6-PHOSPHATE SYNTHASE/PHOSPHATASE (TPS/TPP), DUF581 domain and HSPRO proteins as common SnRK1-associated factors. Study of transcription of SnRK1 subunit genes confirms similar diurnal expression of dark-induced AKINβ1 and AKINβ3 mRNAs. Inhibition of SnRK1 lowers the expression of numerous genes encoding chloroplast functions, decreases the levels of sucrose. Trehalose-6-phosphate (T6P) found to be one of the major SnRK1-inhibitors, confers downregulation of TPS and robust induction of TPP genes of trehalose metabolism, and coordinately activates genes in innate immunity, oxidative stress and cell death responses resulting in ultimate seedling lethality.