The active SnRK1 (Sucrose non-fermenting-1-related protein kinase) form is usually a heterotrimeric complex. Subcellular localization and specific target of the SnRK1 kinase are regulated by specific beta subunits. In Arabidopsis, there are at least seven genes encoding beta subunits, AKINbeta2, one of the SnRK1 kinase is involved in the specificity of interaction of the kinase with the cytosolic nitrate reductase.
