Protein kinase C (PKC) Z has been implicated as a mediator of epidermal growth factor (EGF) receptor (EGFR) signaling in certain cell types. Because EGFR is ubiquitously expressed in squamous cell carcinomas of the head and neck (SCCHN) and plays a key role in tumor progression, we determined whether PKCZ is required for tumor cell proliferation and viability. Examination of total and phosphory...

Histological grading provides prognostic stratification of colorectal cancer (CRC) by scoring heterogeneous phenotypes. Features of aggressiveness include aberrant mitotic spindle configurations, chromosomal breakage, and bizarre multicellular morphology, but pathobiology is poorly understood. Protein kinase C zeta (PKCz) controls mitotic spindle dynamics, chromosome segregation, and multicellu...

Long-term potentiation (LTP) of synaptic transmission has received widespread attention because it is thought to form the physiological basis of learning and memory. A new paper in The EMBO Journal identifies the atypical PKC family member PKCl as an important contributor to the strengthening of the postsynaptic response in LTP. Synaptic transmission in the brain is largely mediated by presynap...

Two splice variants derived from the Bcl-x gene via alternative 50 splice site selection (50SS) are proapoptotic Bcl-x(s) and antiapoptotic Bcl-x(L). Previously, our laboratory showed that apoptotic signaling pathways regulated the alternative 50SS selection via protein phosphatase-1 and de novo ceramide. In this study, we examined the elusive prosurvival signaling pathways that regulate the 50...

BACKGROUND Diabetes mellitus (DM) is characterized by a decreased blood level of glutamine (Gln), which may contribute to the disturbance in the effect of insulin on skeletal muscle. Therefore, it is crucial to study how to improve the effect of insulin on skeletal muscle by increasing Gln. In the present study, we investigated the effect of Gln on the hypoglycemic action of insulin in skeletal...