title: Localization of nucleophosmin in nuclear matrix and changes in its expression during the differentiation of human neuroblastoma induced by retinoic acid.
abstract: In this article, we selectively extracted the nuclear matrix and intermediate filament system of human neuroblastoma SK-N-SH cells pre- and post-treated with retinoic acid (RA). The distribution of nucleophosmin (NPM) in the nuclear matrix and its colocalization with several products of related genes were investigated. Results from two-dimensional gel electrophoresis and MALDI-TOF showed that NPM was a component of the nuclear matrix and its expression in SK-N-SH cells post-treated with RA was down-regulated. Immunofluorescent microscopy observations further showed that NPM was localized in the nuclear matrix of SK-N-SH cells, and its expression level and distribution were altered after treatment with RA. The colocalization of NPM with c-myc, c-fos, p53, and Rb in SK-N-SH cells was observed under a laser scanning confocal microscope, but the colocalization region was changed by RA. Our results prove that NPM is a nuclear matrix protein, which is localized in nuclear matrix fibers. The colocalization of NPM with its related genes and oncogenes affect the differentiation of SK-N-SH cells. The expression of NPM and its distribution in the process of cell differentiation deserve more intensive investigation.
authors.affiliation: The Key Laboratory of Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Science, Xiamen University, Xiamen 361005, PR China.
authors.forename: Song-Lin
authors.initials: SL
authors.lastname: Shi
authors.forename: Ying
authors.initials: Y
authors.lastname: Liang
authors.forename: Qi-Fu
authors.initials: QF
authors.lastname: Li
authors.forename: Qing-Rong
authors.initials: QR
authors.lastname: Liu
authors.forename: Guang-Jun
authors.initials: GJ
authors.lastname: Jing
authors.forename: San-Ying
authors.initials: SY
authors.lastname: Wang
authors.forename: Xiu-Yan
authors.initials: XY
authors.lastname: Zhang
authors.forename: Fu-Yun
authors.initials: FY
authors.lastname: Wu
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects*; D045744:Cell Line, Tumor; D006801:Humans; D009447:Neuroblastoma / Q000503:physiopathology*; D015530:Nuclear Matrix / Q000378:metabolism*; D034521:Nuclear Matrix-Associated Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D000090243:Nucleophosmin; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; C000716967:NPM1 protein, human; D034521:Nuclear Matrix-Associated Proteins; D009687:Nuclear Proteins; D016760:Proto-Oncogene Proteins c-fos; D016271:Proto-Oncogene Proteins c-myc; D016159:Tumor Suppressor Protein p53; D000090243:Nucleophosmin; D014212:Tretinoin