title: Transcription-dependent and transcription-independent nuclear transport of hnRNP proteins.
abstract: Heterogeneous nuclear RNAs and specific nuclear proteins form heterogeneous nuclear ribonucleoprotein complexes (hnRNPs), one of the most abundant components of the nucleus. In mitosis, as the nuclear envelope breaks down, hnRNPs disperse throughout the cell. At the end of mitosis, hnRNPs dissociate and their proteins are transported into the daughter cell nuclei separately. Some are transported immediately (early group), while others are transported later (late group). Transport of the late group appears to require transcription by RNA polymerase II, in that inhibitors of this polymerase cause the late proteins to remain in the cytoplasm. Thus, there are two modes, transcription-dependent and transcription-independent, for the transport of nuclear proteins.
authors.affiliation: Howard Hughes Medical Institute, University of Pennsylvania School of Medicine, Philadelphia 19104-6148.
authors.forename: S
authors.initials: S
authors.lastname: Piñol-Roma
authors.forename: G
authors.initials: G
authors.lastname: Dreyfuss
mesh_terms: D002467:Cell Nucleus / Q000502:physiology* / Q000648:ultrastructure; D003609:Dactinomycin / Q000494:pharmacology; D006367:HeLa Cells / Q000166:cytology / Q000502:physiology; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D006801:Humans; D008938:Mitosis; D009685:Nuclear Envelope / Q000502:physiology / Q000648:ultrastructure; D012319:RNA Polymerase II / Q000037:antagonists & inhibitors / Q000378:metabolism; D012332:RNA, Heterogeneous Nuclear / Q000378:metabolism; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D034441:Heterogeneous-Nuclear Ribonucleoproteins; D012332:RNA, Heterogeneous Nuclear; D012261:Ribonucleoproteins; D003609:Dactinomycin; D012319:RNA Polymerase II