Project description:The urea channel Slc14a2 (or UT-A1) mediates vasopressin-regulated urea transport across the inner medullary collecting duct (IMCD). Previously, UT-A1 was found to present in a high molecular weight complex, suggesting UT-A1 is involved in certain protein-protein interactions. The present study sought to identify the proteins that interact with UT-A1 in this complex for a better understanding of how UT-A1 is regulated. Rat IMCD suspensions were treated with or without V2 receptor agonist, dDAVP, followed by in-cell crosslinking using BSOCOES and detergent solubilization. Immunoprecipitation using Dynabeads coated with UT-A1 specific antibody successfully pulled down the UT-A1 proteins. In-gel digestion protocol was carried out to prepare samples for liquid chromatographic mass spectrometry analysis of tryptic peptides using a Velos-Orbitrap mass spectrometer. The peptides passing stringent spectral quality thresholds were quantified (label-free) to identify those with (UTA-1 antibody/preimmune IgG) >4. A total of 128 UT-A1 interacting proteins were identified. Gene Ontology analysis maps the distribution of these proteins throughout major cell compartments: endoplasmic reticulum, Golgi, endosomes, cytosol and plasma membrane. Among them are four protein kinases (Cdc42bpb, Phkb, Camk2d, Mtor) that play roles in vasopressin-regulated phosphorylation of UT-A1. Non-label quantification was also performed to determine the stoichiometry of UT-A3 with UT-A1, the result does not support an oligomeric complex formation of UT-A1/A3. In conclusion, we have provided a refined list of UT-A1 binding proteins which can be useful for further analysis of the vasopressin signaling pathway in regulation of UT-A1 in IMCD.
Project description:SK-UT-1 uterine leiomyosarcomas (Ut-LMS) cells were transduced with a fatty acid synthase (FASN)-containing retroviral vector to recapitulate the “lipogenic phenotype of cancer.” Consistent with this model, forced expression of FASN enhanced SK-UT-1 proliferation, migration, and cellular motion. Further investigation showed FASN promotes trimethylation of H3K9 (H3K9me3) and acetylation of H3K27 (H3K27ac) in SK-UT-1 cells. In contrast, siRNA targeting of FASN in high endogenous FASN expressing SK-LMS-1 Ut-LMS cells inhibits trimethylation of H3K9 and acetylation of H3K27. Palmitate, the predominant fatty acid product of FASN, increased H3K9me3, H3K27ac and H3K27me3 detection in SK-UT-1 cells. FASN promoted histone 3 methylation and acetylation through alteration of histone 3-modifying enzymatic activities (HDAC, HDM, HMT and HAT).ChIP-seq in SK-UT-1-FASN cells with anti-H3K9me3 antibody identified regions of enriched binding compared to vector-only cells. One differentially-enriched gene, CRISP1, was investigated further by ChIP-PCR. The transcriptionally repressive function of H3K9me3 was confirmed in CRISP1. Our results provide mechanistic insight into the pathobiology of the “lipogenic phenotype of cancer.” Here, FASN reprograms the Ut-LMS epigenome through chromatin remodeling to promote the “malignant phenotype.”
Project description:Low passage head and neck squamous cancer cells (UT-14-SCC) were injected into the flanks of female nu/nu mice to generate xenografts. After tumors reached a size of 500mm3, they were treated with either sham RT or 15 Gy in one fraction. At different time points, days 0, 3, 10 and for controls and days 4, 7, 12, and 21 after irradiation, the tumors were harvested for global gene expression analysis and pathway analysis.
Project description:LNCaP cells were maintained in charcoal-stripped serum containing medium for 48 hours and treated with vehicle or 10 uM of UT-69, UT-155, R-UT-155, or enzalutamide. Twenty four hours after treatment, the cells were harvested, RNA was isolated and expression of genes was measured using microarray (Affymetrix Clarion S)