{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T06:43:21Z","timestamp":1779345801452,"version":"3.51.4"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"1","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1998,4,1]]},"abstract":"<jats:p>The regulatory and catalytic properties of the three mammalian isoforms of protein kinase B (PKB) have been compared. All three isoforms (PKB\u03b1, PKB\u03b2 and PKB\u03b3) were phosphorylated at similar rates and activated to similar extents by 3-phosphoinositide-dependent protein kinase-1 (PDK1). Phosphorylation and activation of each enzyme required the presence of PtdIns(3,4,5)P3 or PtdIns(3,4)P2, as well as PDK1. The activation of PKB\u03b2 and PKB\u03b3 by PDK1 was accompanied by the phosphorylation of the residues equivalent to Thr308 in PKB\u03b1, namely Thr309 (PKB\u03b2) and Thr305 (PKB\u03b3). PKB\u03b3 which had been activated by PDK1 possessed a substrate specificity identical with that of PKB\u03b1 and PKB\u03b2 towards a range of peptides. The activation of PKB\u03b3 and its phosphorylation at Thr305 was triggered by insulin-like growth factor-1 in 293 cells. Stimulation of rat adipocytes or rat hepatocytes with insulin induced the activation of PKB\u03b1 and PKB\u03b2 with similar kinetics. After stimulation of adipocytes, the activity of PKB\u03b2 was twice that of PKB\u03b1, but in hepatocytes PKB\u03b1 activity was four-fold higher than PKB\u03b2. Insulin induced the activation of PKB\u03b1 in rat skeletal muscle in vivo, with little activation of PKB\u03b2. Insulin did not induce PKB\u03b3 activity in adipocytes, hepatocytes or skeletal muscle, but PKB\u03b3 was the major isoform activated by insulin in rat L6 myotubes (a skeletal-muscle cell line).<\/jats:p>","DOI":"10.1042\/bj3310299","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T22:01:27Z","timestamp":1439244087000},"page":"299-308","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":213,"title":["Activation of protein kinase B \u03b2 and \u03b3 isoforms by insulin in vivo and by 3-phosphoinositide-dependent protein kinase-1 in vitro: comparison with protein kinase B \u03b1"],"prefix":"10.1042","volume":"331","author":[{"given":"Kay S.","family":"WALKER","sequence":"first","affiliation":[{"name":"MRC Protein Phosphorylation Unit, Department of Biochemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"DEAK","sequence":"additional","affiliation":[{"name":"MRC Protein Phosphorylation Unit, Department of Biochemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrew","family":"PATERSON","sequence":"additional","affiliation":[{"name":"MRC Protein Phosphorylation Unit, Department of Biochemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kevin","family":"HUDSON","sequence":"additional","affiliation":[{"name":"Zeneca Pharmaceuticals, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Philip","family":"COHEN","sequence":"additional","affiliation":[{"name":"MRC Protein Phosphorylation Unit, Department of Biochemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dario R.","family":"ALESSI","sequence":"additional","affiliation":[{"name":"MRC Protein Phosphorylation Unit, Department of Biochemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/331\/1\/299\/630926\/bj3310299.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/331\/1\/299\/630926\/bj3310299.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,24]],"date-time":"2021-11-24T00:41:48Z","timestamp":1637714508000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/331\/1\/299\/34518\/Activation-of-protein-kinase-B-and-isoforms-by"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1998,4,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1998,4,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj3310299","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[1998,4,1]]}}}