What type of kinase is AMPK?
What type of kinase is AMPK?
serine/threonine protein kinase complex
AMPK is a serine/threonine protein kinase complex consisting of a catalytic α-subunit (α1 and α2), a scaffolding β-subunit (β1 and β2) and a regulatory γ-subunit (γ1, γ2 and γ3; Figure 1).
What happens when AMPK is phosphorylated?
This finding suggests that Thr172 phosphorylation of AMPK is the critical factor for phosphorylation of its downstream targets in a cellular context. Activation loop phosphorylation promotes the stabilisation of the active conformation of this loop and the positioning of key residues in the kinase domain.
Is TSC2 a kinase?
The 5′-AMP-sensitive kinase phosphorylates TSC2 (residues T1271 and S1387) thereby preventing the inhibitory control by AKT2. The active TSC1/2 complex maintains RHEB in its GDP-bound state thus preventing activation of mTORC1. Protein synthesis is suppressed and autophagy is no longer prevented.
What inactivates AMPK?
AMPK inhibits mTOR through direct phosphorylation of TSC2 tumor suppressor (Inoki et al., 2003) as well as critical mTOR-binding subunit raptor (Gwinn et al., 2008). Recent studies demonstrated that AMPK activity is suppressed by amino acids (Gleason et al., 2007; Leclerc and Rutter, 2004).
How do you get tuberous sclerosis?
Tuberous sclerosis is caused by changes (mutations) in either the TSC1 or TSC2 gene. These genes are involved in regulating cell growth, and the mutations lead to uncontrolled growth and multiple tumours throughout the body.
How does phosphorylation of TSC2 regulate cell size?
Phosphorylation of TSC2 by AMPK is required for translation regulation and cell size control in response to energy deprivation. Furthermore, TSC2 and its phosphorylation by AMPK protect cells from energy deprivation-induced apoptosis.
What are mutations in TSC1 and TSC2?
Mutations in either the TSC1 or TSC2 tumor suppressor gene are responsible for Tuberous Sclerosis Complex. The gene products of TSC1 and TSC2 form a functional complex and inhibit the phosphorylation of S6K and 4EBP1, two key regulators of translation.
What does the AMP activated protein kinase do?
The AMP-activated protein kinase (AMPK) system acts as a sensor of cellular energy status that is conserved in all eukaryotic cells.
What are the subunits of the AMPK complex?
The AMPK complex contains 3 subunits, with the α subunit being catalytic, the β subunit containing a glycogen-sensing domain, and the γ subunits containing 2 regulatory sites that bind the activating and inhibitory nucleotides AMP and ATP.
What type of kinase is AMPK? serine/threonine protein kinase complex AMPK is a serine/threonine protein kinase complex consisting of a catalytic α-subunit (α1 and α2), a scaffolding β-subunit (β1 and β2) and a regulatory γ-subunit (γ1, γ2 and γ3; Figure 1). What happens when AMPK is phosphorylated? This finding suggests that Thr172 phosphorylation of AMPK…