Is pyruvate kinase phosphorylated by PKA?

Pyk1 (pyruvate kinase 1) from Saccharomyces cerevisiae was characterized as a substrate for PKA (protein kinase A) from bovine heart and yeast. The Ksp* values for Pyk1 and Pyk1 T94A were the same, indicating that both proteins are phosphorylated at the same site by PKA.

What phosphorylates pyruvate kinase?

Pyruvate kinase has been found to be allosterically activated by FBP and allosterically inactivated by ATP and alanine.

How does F16BP affect pyruvate kinase?

Pyruvate Kinase Form 1 and Form 2 activity in the presence (blue circles) and absence (red circles) of F16BP. How does F16BP affect pyruvate kinase? F16BP is an inhibitor of Form 1. F16BP is an inhibitor of Form 2.

What is pyruvate kinase inhibited by?

ATP allosterically inhibits both the L and the M forms of pyruvate kinase to slow glycolysis when the energy charge is high. Finally, alanine (synthesized in one step from pyruvate, Section 24.2. 2) also allosterically inhibits the pyruvate kinases—in this case, to signal that building blocks are abundant.

What does pKa stand for in protein kinase?

Protein kinases are used to add phosphate groups to proteins. The one shown here is cAMP-dependent protein kinase, also known as protein kinase A or PKA (PDB entries 3tnp , 1j3h and 2h9r ).

Why is pyruvate kinase not called a phosphorylation kinase?

Pyruvate kinase was inappropriately named (inconsistently with a conventional kinase) before it was recognized that it did not directly catalyze phosphorylation of pyruvate, which does not occur under physiological conditions.

How is WNK4 phosphorylation regulated by PKC and pKa?

WNK4 levels are regulated by binding to Kelch-like 3, targeting WNK4 for ubiquitylation and degradation. Phosphorylation of Kelch-like 3 by PKC or PKA downstream of AngII or vasopressin signaling, respectively, abrogates binding. We tested whether these pathways also affect WNK4 phosphorylation and activity.

How does pKa affect the production of energy?

This activates PKA, which then phosphorylates many proteins involved in generation of cellular energy, regulating proteins like glycogen synthase and pyruvate kinase directly and also changing the synthesis of proteins by phosphorylating key transcription factors.