Premium
Increased expression of the MBP mRNA binding protein HnRNP A2 during oligodendrocyte differentiation
Author(s) -
Maggipinto M.,
Rabiner C.,
Kidd G.J.,
Hawkins A.J.,
Smith R.,
Barbarese E.
Publication year - 2004
Publication title -
journal of neuroscience research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.72
H-Index - 160
eISSN - 1097-4547
pISSN - 0360-4012
DOI - 10.1002/jnr.20014
Subject(s) - heterogeneous nuclear ribonucleoprotein , cytoplasm , microbiology and biotechnology , biology , myelin basic protein , heterogeneous ribonucleoprotein particle , ribonucleoprotein , phosphorylation , oligodendrocyte , messenger rna , rna binding protein , myelin , rna , biochemistry , gene , neuroscience , central nervous system
Heterogeneous nuclear ribonucleoprotein (hnRNP) A2, a trans ‐acting factor that mediates intracellular trafficking of myelin basic protein (MBP) mRNA to the myelin compartment in oligodendrocytes, is most abundant in the nucleus, but shuttles between the nucleus and cytoplasm. In the cytoplasm, it is associated with granules that transport mRNA from the cell body to the processes of oligodendrocytes. We found that the overall level of hnRNP A2 increased in oligodendrocytes as they differentiated into MBP‐positive cells, and that this augmentation was reflected primarily in the cytoplasmic pool of hnRNP A2 present in the form of granules. The extranuclear distribution of hnRNP A2 was also observed in brain during the period of myelination in vivo. Methylation and phosphorylation have been implicated previously in the nuclear to cytoplasmic distribution of hnRNPs, so we used drugs that block methylation and phosphorylation of hnRNPs to assess their effect on hnRNP A2 distribution and mRNA trafficking. Cultures treated with adenosine dialdehyde (AdOx), an inhibitor of S ‐adenosyl‐ L ‐homocysteine hydrolase, or with 5,6‐dichloro‐1‐β‐ D ‐ribofuranosylbenzimidazole (DRB), a drug that inhibits casein kinase 2 (CK2), maintained the preferential nuclear distribution of hnRNP A2. Treatment with either drug affected the transport of RNA trafficking granules that remained confined to the cell body. © 2004 Wiley‐Liss, Inc.