A New Strategy for Studying Protein Kinase B and Its Three Isoforms. Role of Protein Kinase B in Phosphorylating Glycogen Synthase Kinase-3, Tuberin, WNK1, and ATP Citrate Lyase

• Published in: Biochemistry (Easton) 2006-01, Vol.45 (1), p.213-223
• Main Authors: Sale, Elizabeth M, Hodgkinson, Conrad P, Jones, Neil P, Sale, Graham J
• Format: Article
• Language: English
• Subjects: 3T3 Cells; Adipocytes - cytology; Adipocytes - metabolism; Animals; ATP Citrate (pro-S)-Lyase - metabolism; Cells, Cultured; DNA - biosynthesis; Glycogen Synthase Kinase 3 - metabolism; Glycogen Synthase Kinase 3 beta; Insulin - pharmacology; Isoenzymes - metabolism; Mice; Minor Histocompatibility Antigens; Oligonucleotide Probes; Phosphorylation; Protein Isoforms - metabolism; Protein Kinase C - metabolism; Protein-Serine-Threonine Kinases - metabolism; Proto-Oncogene Proteins c-akt - metabolism; Tumor Suppressor Proteins - metabolism; WNK Lysine-Deficient Protein Kinase 1
• ISSN: 0006-2960; 1520-4995
• DOI: 10.1021/bi050287i

Protein kinase B appears to play a key role in insulin signaling and in the control of apoptosis, although the precise targets of PKB are incompletely understood. PKB exists as three isoforms (α, β, and γ) that may have unique as well as common functions within the cell. To facilitate understanding the precise roles of PKB and its isoforms, novel tools of widespread applicability are described. These tools are antisense oligonucleotide probes that enable the specific and potent knock down of endogenous PKB α, β, or γ isoforms, individually or in various combinations, including concurrent removal of all three isoforms. The probes were applied to dissect the role of PKB in phosphorylating glycogen synthase kinase-3 (GSK-3), a critical mediator in multiple responses, and other potentially key targets. Triple antisense knock down of PKB α, β, and γ so that total PKB was