Project description:The multitude of obesogenic diets used in rodent studies is enormous and thus hardly manageable. Since standardization is missing and it is presumed that individual compositions provoke individual effects, the choice of quality, quantity and combination of diet ingredients seems to be crucial for the outcome and interpretation of obesity studies. Therefore, the present study was conducted to compare the effects of three commonly used obesogenic diets on selected parameters. Besides basic phenotypic and metabolic characterization, one main aspect was a comparative liver proteome analysis. As expected, the obtained results picture differentiated consequences mainly depending on fat source and/or fat- and sugar quantity. By confirming the general presumption that the choice of nutritional composition is a pivotal factor, the present findings demonstrate that a conscious selection is indispensable for obtaining reliable and sound results in obesity research.In conclusion, we strongly recommend a thorough selection of the appropriate obesogenic diet prior to an experiment and in consideration of the individual research question.
Project description:Keratin cytoskeletal proteins are crucial for the maintenance of skin integrity. Mutations in genes coding for K5 and K14 cause the human skin disorder epidermolysis bullosa simplex (EBS) leading to substantial alterations in keratin assembly and collapse of keratin filaments into cytoplasmic protein aggregates. The phenotypic consequences of K5 and K14 mutations comprise fragility of basal keratinocytes and skin blistering upon mild mechanical trauma. Treatment of EBS is only supportive and consists primarily of wound care and avoidance of mechanical stress. Besides symptomatic care, no efficient therapeutic treatment is available for EBS. In the present study, we used patient-derived keratinocytes carrying the most frequent K14.R125C mutation as a reproducible EBS model to understand EBS pathomechanisms and to develop a therapy approach aimed to restore a functional keratin network. Numerous post-translational modifications (PTMs) such as phosphorylation have been reported to occur on keratins, which affect the organization of keratin networks. Whether keratin mutations affect the occurrence of PTMs and thereby keratin aggregation in EBS is yet unknown. We find that the K14.R125C mutation alters keratin and keratin-associated protein PTMs in distinct ways and suggest that disease mutations and altered PTMs aggravate keratin aggregation. We reason that chemical compounds affecting the interplay of mutations and PTMs enable the reformation of a keratin cytoskeleton from aggregates are potential candidates for combating EBS.
Project description:We overexpressed eGFP, eGFP-SPP and pmRFP-Q74 construct in HEK93 cells. We made immunoprecipitation of GFP. We compare the interactome of eGFP and eGFP-SPP.
Project description:In chronic lymphocytic leukemia (CLL), the tumor cells receive survival support from stromal cells through direct cell contact, soluble factors and extracellular vesicles. The tyrosine protein kinase Lyn, is aberrantly expressed in the malignant and stromal cells in CLL tissue. We therefore studied the role of Lyn in the EV-based communication and tumor support. We compared the Lyn-dependent EV release, uptake and functionality using Lyn-proficient and deficient stromal cells and primary CLL cells. Lyn-proficient cells caused a significantly higher EV release and EV uptake as compared to Lyn-deficient ones. Also, they induced stronger support of primary CLL cells. Proteomic comparison of the EVs from Lyn-proficient and deficient stromal cell highlighted 72 significantly differentially expressed proteins, many of which belonging to the extracellular matrix organization, such as collagen, nidogen, fibronectin and endosialin (CD248). CD248, a marker of certain tumors and of cancer associated fibroblast (CAF) was significantly depleted in Lyn-deficient HS-5 cells. A knockdown of CD248 in Lyn+ HS-5 cells resulted in a diminished B-CLL cells survival feeding capacity compared to wildtype or scrambled control cells. The presented data provide preclinical evidence, that the tyrosine kinase Lyn crucially influences the EV-based communication between stromal and primary B-CLL cells by raising the EV release and their concentration of functional molecules, such as endosialin.
Project description:The experiment was performed to identify phosphorylation target proteins of cAMP-dependent kinase A (PKA) in mouse brain tissue. Therefore, coimmunoprecipitation analysis was performed using a PKA phosphorylation state-specific antibody (RRXS/T). Potential PKA target proteins were determined by LC-MS/MS.