Additive Anti-Tumor Effects of Lovastatin and Everolimus In Vitro through Simultaneous Inhibition of Signaling Pathways

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedThis work was supported by a research grant from the Ludwig-Maximilians University of Munich (Förderprogramm für Forschung und Lehre [FöFoLe], grant number 865/829)

The 14-3-3ζ Protein Binds to the Cell Adhesion Molecule L1, Promotes L1 Phosphorylation by CKII and Influences L1-Dependent Neurite Outgrowth

BACKGROUND: The cell adhesion molecule L1 is crucial for mammalian nervous system development. L1 acts as a mediator of signaling events through its intracellular domain, which comprises a putative binding site for 14-3-3 proteins. These regulators of diverse cellular processes are abundant in the brain and preferentially expressed by neurons. In this study, we investigated whether L1 interacts with 14-3-3 proteins, how this interaction is mediated, and whether 14-3-3 proteins influence the function of L1. METHODOLOGY/PRINCIPAL FINDINGS: By immunoprecipitation, we demonstrated that 14-3-3 proteins are associated with L1 in mouse brain. The site of 14-3-3 interaction in the L1 intracellular domain (L1ICD), which was identified by site-directed mutagenesis and direct binding assays, is phosphorylated by casein kinase II (CKII), and CKII phosphorylation of the L1ICD enhances binding of the 14-3-3 zeta isoform (14-3-3ζ). Interestingly, in an in vitro phosphorylation assay, 14-3-3ζ promoted CKII-dependent phosphorylation of the L1ICD. Given that L1 phosphorylation by CKII has been implicated in L1-triggered axonal elongation, we investigated the influence of 14-3-3ζ on L1-dependent neurite outgrowth. We found that expression of a mutated form of 14-3-3ζ, which impairs interactions of 14-3-3ζ with its binding partners, stimulated neurite elongation from cultured rat hippocampal neurons, supporting a functional connection between L1 and 14-3-3ζ. CONCLUSIONS/SIGNIFICANCE: Our results suggest that 14-3-3ζ, a novel direct binding partner of the L1ICD, promotes L1 phosphorylation by CKII in the central nervous system, and regulates neurite outgrowth, an important biological process triggered by L1

Tree and cold storage influence on incidence of albedo breakdown, textural properties of the rind and fruit quality in 'Washington Navel' orange

Introduction. Albedo breakdown (AB) causes serious economic losses to sweet orange growers. The growers practice delayed harvesting (tree storage) to extend the fresh fruit supply to market. We investigated the effects of tree storage and cold storage on AB incidence, textural properties of the rind and fruit quality. Materials and methods. Fruit of ‘Washington Navel’ orange were harvested at the commercial maturity stage (3rd July) and then 31, 62 and 93 days after the harvest. The AB incidence, textural properties of the rind and fruit quality were assessed in one lot of fruit after harvest and a second lot after 31, 62 and 93 days of cold storage (5 °C). Results and discussion. The AB incidence increased from 65% to 89% from the first to the last harvest, respectively. Extended storage periods reduced rind hardness and fruit firmness, and increased the rind tensile force irrespective of the storage type. The rind hardness, tensile force and fruit firmness were higher in cold-stored fruit than fruit stored for 93 days on the tree. The soluble solids concentration: titratable acidity (SSC:TA) ratio in juice increased with the extended storage period in both types of storage. The increase in SSC:TA was more pronounced at 62 and 93 days in cold-stored than tree-stored fruit. The concentrations of fructose and glucose in the juice of fruit stored on the tree for 93 days were higher than in the cold-stored fruit, and sucrose showed the reverse trend. Conclusion. The cold-stored fruit exhibited a higher rind hardness, rind tensile force, firmness and SCC:TA ratio, lower concentrations of citric acid, malic acid, fructose and glucose, and lower AB incidence than the tree-stored fruit. These findings indicate a preference for cold storage over tree storage for the orange fruit quality