Unsaturated diacylglycerol as a possible messenger for the activation of calcium-activated, phospholipid-dependent protein kinase system

Calcium‐activated, phospholipid‐dependent protein kinase in rat pancreas islets of langerhans

“…Calmodulin showed no effect over a wide range of concentrations. These properties of the islet protein kinase C were very similar to those of the enzyme originally found in rat brain soluble fraction [10][11][12][13].…”

“…Synthetic diolein was purchased from Nakarai Chemicals. [7.32p] ATP, calf thymus H1 histone, various lipids, and other chemicals employed for the present studies were prepared as specified in [10][11][12][13][14][15][16]. All reagents were taken up in water which was prepared by a double distillation apparatus followed by passing through a Chelex 100 column to remove Ca 2÷ as in [13].…”

“…In [ 10,11 ], a new species of protein kinase (protein kinase C) was described which absolutely requires Ca 2+ and phospholipid. Protein kinase C is usually present as an inactive form, but is activated by diacylglycerol which may be transiently produced from PI during its receptor-linked turnover [12,13]. In [14][15][16], protein kinase C was shown to play an indispensable role in the thrombin-induced release of serotonin in human platelets.…”

Identification of the primary growth response gene, ST2/T1, as a gene whose expression is differentially regulated by different protein kinase C isozymes

“…differentiation, gene expression, membrane transport as well as secretion of hormones and neurotransmitters (see [1][2][3] for reviews). Initially, PKC was described as a Ca 2+-and phospholipid-dependent serine/threonine kinase [4,5], and later it was shown to be the major intracellular receptor for the tumorpromoting phorbol esters [6,7]. cDNA cloning and careful examination of the encoded proteins has revealed that the members of the PKC family can be classified into three major groups, namely, classical, cPKCs-c~, -/31, -1~II and -y, [8]; novel, nPKCs-~, -e, -/7, -0, and -¢t [9][10][11][12][13][14][15]; and atypical, aPKCs -5 and -t (the human counterpart of mouse aPKC-2) [10,1618].…”

Historical review of research on protein kinase C in learning and memory

“…In the late 1960s and early 1970s it became apparent that rapid enhancement of PIturnover occurred in a large variety of tissues and could be evoked by numerous (extracellular) stimuli (Lapetina and Michell, 1973). Nevertheless, the physiological significance of such PI-turnover remained unclear until the late 197Os, when Takai et al (1979a) Hence it induced a long lasting enhancement of the excitability of these cells. Before this report, there was no direct evidence for the involvement of PKC in the control of neuronal excitability.…”