Regulatory subunit of the probable trimeric SNF1-related protein kinase (SnRK) complex, which may play a role in a signal transduction cascade regulating gene expression and carbohydrate metabolism in higher plants. The SnRK complex may also be involved in the regulation of fatty acid synthesis by phosphorylation of acetyl-CoA carboxylase and in assimilation of nitrogen by phosphorylating nitrate reductase. Subunit of a probable heterotrimeric complex consisting of an alpha catalytic (KIN10 or KIN11) subunit, and a beta (KINB) and a gamma (KING or SNF4) non-catalytic regulatory subunits (PubMed:17028154, PubMed:25736509). Interacts with SNF4. Interacts with FLZ1, FLZ2, FLZ8, FLZ9, FLZ10, FLZ12, FLZ13 and FLZ14 (PubMed:29945970). A number of isoforms are produced. According to EST sequences. Expressed in leaves, stems, roots, flower buds and flowers. Not detectable in siliques. Repressed in the dark. Kinase-interacting sequence (KIS) is specific for the alpha catalytic subunit interaction and Association with SNF1 Complex (ASC) is specific for the gamma non-catalytic regulatory subunit interaction. Sumoylated. Belongs to the 5'-AMP-activated protein kinase beta subunit family.