Proteomic identification of hnRNP family members and other proteins involved in splicing in human cultured cells

Abstract

Introduction. Heterogeneous nuclear ribonucleoprotein A1 (hnRNP А1) and other RNA-binding proteins involved in splicing participate in realization of genetic information and can be greatly changed in pathological conditions including tumors. Objective. Proteomic study of hnRNP A1 and other RNA-binding splicing proteins in 10 human malignant and non-malignant cultured cell lines of mesenchymal and epithelial origin. Materials and methods. Two-dimensional gel electrophoresis of adenocarcinomas (LNCaP, DU-145, PC-3, 769-P) and sarcomas (U2-OS, SK-UT-1B, RD) cell lines with following protein identification by matrix-assisted laser desorption ionization mass spectrometry have been carried out. Results. HnRNP А1 has been identified as an abundant protein in all studied malignant cell lines. It has been revealed in lower amount in normal mesenchymal cells compared to malignant cultured cells and achieved undetectable levels in myoblasts after induction of differentiation. Conclusion. High cellular level of hnRNP А1 can suggest high proliferative activity of cells including malignant those. Hence, hnRNP А1 and other RNA-binding splicing proteins hold promise to its further investigation in human transformed cells.

Heterogeneous Nuclear Ribonucleoproteins Involved in the Functioning of Telomeres in Malignant Cells

“…In addition, in a comparative proteomic study, it was shown that the content of hnRNP-A1 in cancer cells is usually higher than in adjacent normal tissues [68]. In our laboratory, a proteomic analysis of ten cultured HMC lines revealed hnRNP-A1 as one of the 500 most abundant proteins [69].…”

“…Information on the third transcript of the HNRNPA1 gene is extremely limited (P09651-3 UniProt). Nonetheless, recently, in our laboratory, trace amounts of the corresponding protein product in human mesenchymal stem cells (SC5-MSC) were detected by proteomic analysis [69].…”

“…HnRNP-A1 and some other members of the hnRNP-A/B family are present not only in HMCs but also in various normal human cells, including the cells of tissues adjacent to malignant tumors [64,68,69,182,183]. However, the content of hnRNP-A1 in normal cells (or normal tissues) is usually significantly lower compared with HMCs [68,69,159,184]. Currently, it is believed that hnRNP-A1 (and some other members of the hnRNP-A/B family) is involved in both normal and pathological RNA metabolism [50].…”