Commentary on ‘Effects of acetylcholine on the turnover of phosphoryl units in individuals phospholipids of pancreas slices and brain cortex slices’ by L.E. Hokin and M.R. Hokin Biochim. Biophys. Acta 18 (1955) 102–110

Activation of protein kinase C is not an absolute requirement for amylase release from permeabilized rat pancreatic acini

“…The effects of cAMP and PMA to increase amylase release would be consistent with Cl--mediated granule lysis, as the Cl--permeability of the granules is known to be enhanced by both protein kinase A and PKC activity (Fuller etal., 1989). The use of pH 7 buffer is also of concern, as the zymogen granules are known to become increasingly fragile at higher pH (Hokin, 1955;Holtzer & Van Lancker, 1963).…”

Participation of acid phospholipids in protein translocation across the bacterial cytoplasmic membrane

“…The necessity of phosphatidylinositol resynthesis during stimulation of secretion in pancreas [27] and the significant role of phospholipids in protein import into mitochondria [44] confirm this assumption.…”

Phosphatidylinositol Phosphate Kinases, a Multifaceted Family of Signaling Enzymes

“…Therefore, in vitro the PIPKIIs are predominantly 4-kinases and appear to be less promiscuous in their substrate usage than PIPKIs. In summary, the in vitro substrate preference of the PIPKII isoforms is PI-5-P Ͼ PI-3-P Ͼ PI-4-P, 2 whereas the efficacy of substrate usage for characterized PIPKI isoforms is PI-4-P Ͼ PI-3-P Ͼ PI-3,4-P 2 Ͼ PI-5-P ϭ PI (14 -18, 33-38). The spectrum of messengers generated and substrates used by specific kinases in vivo is presumably tightly regulated.…”

“…The PIPKs contain a similar conserved sequence, the "DLKGS" motif, that had been suggested as a counterpart (25). Although mutation of Asp-216 in the DLKGS destroys activity, 2 the structure of PIPKII␤ demonstrated that these two motifs are not equivalent. The counterpart of the PKA Asp-166, in the RDLK, is Asp-278 in the PIPKII␤ structure.…”