Thesis (M. Med. Sc.)--University of Hong Kong, 2006.

Thesis (Ph. D.)--Washington State University, August 2007. / Includes bibliographical references.

Calcium/phospholipid-dependent protein kinase (PKC) was purified from P1798 lymphosarcoma. It was demonstrated that uncomplexed calcium and uncomplexed phosphatidylserine are the activators, that the activation of PKC requires that calcium bind first, that the activation of PKC requires that calcium bind first, that high calcium concentrations inhibit PKC activation, and that calcium inhibition can be overcome by phosphatidylserine.

Nonmuscle myosin from bovine thymus was purified, characterized , and phosphorylated with MLCK, H4PK, and Protein Kinase C. Phosphorylation occured exclusively on the myosin regulatory light chain. Phosphorylation by MLCK and H4PK resulted in the activation of the MgATPase activity as well as filament assembly of nonmuscle myosin.

Calcium/calmodulin-dependent protein kinase II (CaM kinase II) is demonstrated to exist in the ß-cell and immunopecipitation. Glucose and potassium significantly stimulate the rapid autophosphorylation of CaM kinase II and proportionally induce autonomous activity of the kinase in a dose-dependent manner that parallels insulin secretion. The activation of CaM kinase II, alloxan, KN-62 and KN-93, suggest that the enzyme is an integral component of insulin secretion and/or related processes in the β-cell.

No description available.

Thesis (Sc.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The c-Jun NH2-terminal kinase (JNK) and p38 intracellular signaling cascades are mitogen-activated protein kinase (MAPK) signaling pathways that are activated in mammalian cells by a variety of stressors, including proinflammatory cytokines, osmotic shock, and shear stress. The purpose of this dissertation research was to examine the effect of injury-producing exercise on JNK and p38 activities in human skeletal muscle and to determine whether mechanical stress is a primary stimulator of JNK and p38 activities with contraction. Twelve healthy subjects (7M/5F) completed maximal concentric or eccentric knee extensions on an isokinetic dynamometer (10 sets, 10 reps). Needle biopsies were obtained from the vastus lateralis muscle 24 h before exercise, immediately post-exercise, and 6 h post-exercise. While both forms of exercise increased JNK activity immediately post-exercise, eccentric contractions resulted in a much higher activation (15-fold vs. 4-fold increase above basal for eccentric and concentric, respectively). By 6 h post-exercise, JNK activity decreased back to baseline values. In a separate study, 14 male subjects completed a 42.2 km marathon. Biopsies were obtained from the vastus lateralis muscle 10 days prior to the marathon, immediately following the race, and 1, 3, and 5 days after the race. JNK activity increased 7-fold over basal immediately postexercise, but decreased back to basal 1, 3, and 5 days after the exercise. The activity of p38y also was increased and decreased in a similar pattern. However, no regulation was observed for p38α. In a third study, the effects of contraction and static stretch on JNK activity and p38 phosphorylation were determined in the rat soleus muscle in vitro. Static stretch dramatically increased JNK activity and p38 phosphorylation, whereas isometric contraction resulted in much smaller increases in JNK activity and p38 phosphorylation. The regulation of focal adhesion proteins also was examined following both exercise and contraction. The work presented in this thesis demonstrates that injury-producing exercise results in the marked activation of the JNK and p38 stress-activated protein kinases and provides evidence that mechanical stress may be a major contributor to increases in JNK and p38 activities observed following contraction in rat and human skeletal muscle. / 2999-01-01

Purified S6/H4 kinase (Mr 60,000) requires autophosphorylation for activation. A rabbit anti-S6/H4 kinase peptide (SVIDPVPAPVGDSHVDGAAK) antibody recognized both the S6/H4 kinase holoenzyme and catalytic domain. Immunoreactivity with p60 kinase protein, and S6/H4 kinase activity were precisely correlated in fractions obtained from ion exchange chromatography of P1798 lymphosarcoma extracts. An enzyme which catalyzed the MgATP-dependent phosphorylation and activation of S6/H4 kinase coeluted with immunoreactivity from Mono 5, but not Mono Q chromatography. Since S6/H4 kinase is homologous with rac-activated PAK65, the observation that phosphorylation is also required for activation suggests a complex mechanism for in vivo activation of the S6/H4 kinase.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [76]-87).

Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [68]-80).