Heterogeneous nuclear ribonucleoproteins (hnRNPs) are structurally and functionally distinct proteins containing specific domains and motifs that enable the proteins to bind certain nucleotide sequences, particularly those found in human telomeres. In human malignant cells (HMCs), hnRNP-A1-the most studied hnRNP-is an abundant multifunctional protein that interacts with telomeric DNA and affects telomerase function. In addition, it is believed that other hnRNPs in HMCs may also be involved in the maintenance of telomere length.
View Article and Find Full Text PDFThe mitochondrial set of proteins is a dynamic system, crucial for multiple functions of this organelle. Differential expression of genes in various tissues, alternative splicing, post-translational modifications, turnover and spatial dynamics of proteins are the factors that influence mitochondrial proteomes increasing their versatility. A wide range of high-throughput proteomic approaches are extensively used for identification, quantification and functional assessment of human and other mammalian mitochondrial proteins.
View Article and Find Full Text PDFIdentification of actin-depolymerizing factor homology (ADF-H) domains in the structures of several related proteins led first to the formation of the ADF/cofilin family, which then expanded to the ADF/cofilin superfamily. This superfamily includes the well-studied cofilin-1 (Cfl-1) and about a dozen different human proteins that interact directly or indirectly with the actin cytoskeleton, provide its remodeling, and alter cell motility. According to some data, Cfl-1 is contained in various human malignant cells (HMCs) and is involved in the formation of malignant properties, including invasiveness, metastatic potential, and resistance to chemotherapeutic drugs.
View Article and Find Full Text PDFSplicing factor, proline- and glutamine-rich protein (SFPQ), was identified in eight human cultivated cell lines by proteomic approaches. The cell proteins have been separated by means of two-dimensional gel electrophoresis in two modifications and identified by matrix-assisted laser desorption ionization mass spectrometry with further tandem mass spectrometry. The analysis of proteins from three human sarcomas cell lines (RD, U-2 OS and SK-UT-1B), three human renal adenocarcinomas cell lines (A-498, 769-P and OKP-GS), and two prostate adenocarcinomas cell lines (DU-145 and PC-3) revealed several electrophoretic isoforms of SFPQ protein.
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