A single RNA recognition motif in splicing factor ASF/SF2 directs it to nuclear sites of adenovirus transcription.
SR protein ASF/SF2 is a general pre-mRNA splicing factor as well as a regulator of alternative splicing. Data presented here show that ASF/SF2 is efficiently recruited to sites in the nucleus where adenovirus genes are transcribed and the resulting pre-mRNAs are processed. At the intermediate stages of a productive infection, ASF/SF2 colocalizes with small nuclear ribonucleoprotein particles (snRNPs), splicing factors in ring-like structures surrounding viral replication centres and, at late stages of the infection, in enlarged speckles. Results presented here demonstrate that ASF/SF2 requires only one of the two RNA-recognition motifs (RRMs) present in the protein for its efficient recruitment to the ring-like structures, where viral pre-mRNAs are transcribed and processed, and that the arginine/serine-rich (RS) domain in ASF/SF2 is both redundant and insufficient for the translocation of the protein to active viral RNA polymerase II genes in adenovirus-infected cells.
Department of Medical Biochemistry & Microbiology, Unit of Microbiology, Uppsala University, Box 582, S-751 23 Uppsala, Sweden.
Anette
A
Lindberg
Institute of Histology and Embryology, Faculty of Medicine, University of Lisbon, 1699 Lisboa Codex, Portugal.
Margarida
M
Gama-Carvalho
Institute of Histology and Embryology, Faculty of Medicine, University of Lisbon, 1699 Lisboa Codex, Portugal.
Maria
M
Carmo-Fonseca
Department of Medical Biochemistry & Microbiology, Unit of Microbiology, Uppsala University, Box 582, S-751 23 Uppsala, Sweden.
Jan-Peter
JP
Kreivi
D000256:Adenoviridae / Q000235:genetics*; D015967:Gene Expression Regulation, Viral / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D009687:Nuclear Proteins / Q000235:genetics*; D012326:RNA Splicing / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics; D016601:RNA-Binding Proteins; D017411:Ribonucleoproteins, Small Nuclear / Q000235:genetics / Q000378:metabolism; D000068103:Serine-Arginine Splicing Factors; D014158:Transcription, Genetic
D009687:Nuclear Proteins; D012333:RNA, Messenger; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D017411:Ribonucleoproteins, Small Nuclear; D000068103:Serine-Arginine Splicing Factors