A 20-aa synthetic peptide sequence mapping near the C-terminus of mouse AMPK-a1 (1)
No significant sequence homology is seen with AMPK-a2 or other proteins
Species crossreactivity: The peptide is 95% conserved in rat and human AMPK-a1.
In cells, excess of metabolic fuel is converted into fatty acids in cytosol and oxidized later in mitochondria to generate ATP and acetyl-CoA. In fatty acid synthesis, catalytic formation of malonyl-CoA (precursor for long-chain fatty acyl-CoA, LCFA-CoA) from acetyl-CoA by Acetyl-CoA carboxylase (ACC-1) is the rate limiting step. The translocation of LCFA-CoA from cytosol to mitochondria, catalyzed by two carnitine palmitoyl transferases (CPT-1 & CPT-2) and regulated by ACC-2, is the rate limiting step of mitochondrial fatty acid ?-oxidation. Activities of ACC-1, ACC-2 and other key proteins of carbohydrate and fat metabolism are regulated by their phosphorylation by 5'-AMP-activated protein kinase (AMPK). AMPK switches-off biosynthetic processes when ATP levels are depleted and AMP rises in response to fuel deficiency and treatments like heat shock, ischaemia and exercise. A defect in AMPK switch leads to insulin resistance, dyslipidemia, ketosis resistance and other metabolic derangements in Type 2 diabetes. AMPK also regulates cholesterol biosynthesis via phosphorylation and inactivation of hormone-sensitive lipase and hydroxymethylglutaryl-CoA resuctase. It also appears to act as a metabolic stress-sensing protein kinase switching off biosynthetic pathway when ATP levels are depleted and when 5-AMP rises in response to fuel limitation and or hypoxia. AMPK is a heterotrimer of a catalytic subunit a (~63kD), and two non-catalytic subunits, b (~40kD) and g (~38kD). These subunits exist in multiple isoforms (a1, a2, b1, b2, g1 and g2). Coexpression of all three subunit is required for kinase activity. The expression of a2 subunit (552aa) is most abundant in skeletal muscle with lower levels in liver, heart, lung and kidney. In contrast, a1 subunit (548aa) is expressed at very low levels in all the tissues. AMPK-a1 or AAK-1 is more AMP dependent than AMPK-a2. The aa sequences of a1 and a2, in their catalytic core and C-terminal tails are ~90 % and 60 %, respectively, identical.
Applications:Suitable for use in ELISA. Not suitable for use in Western Blot. Other applications not tested.
Recommended Dilution:ELISA: 50-100ng of control peptide/well
Optimal dilutions to be determined by the researcher.
Storage and Stability:May be stored at 4°C for short-term only. For long-term storage, store at -20°C. Aliquots are stable for at least 6 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
