Cloning and intracellular localization of the U2 small nuclear ribonucleoprotein auxiliary factor small subunit
Graduate School of Biomedical Sciences; Department of Biochemistry and Molecular Pharmacology; Program in Molecular Medicine; Program in Gene Function and Expression
Medical Subject Headings
Amino Acid Sequence; Base Sequence; Cell Nucleus; Gene Expression; Hela Cells; Humans; Macromolecular Substances; Molecular Sequence Data; Nuclear Proteins; RNA Splicing; RNA, Messenger; RNA, Small Nuclear; Ribonucleoproteins; Ribonucleoproteins, Small Nuclear
Life Sciences | Medicine and Health Sciences
U2 small nuclear ribonucleoprotein auxiliary factor (U2AF), an essential mammalian splicing factor, is composed of two subunits: a 65-kDa protein (U2AF65), which binds the pre-mRNA polypyrimidine tract and is required for in vitro splicing, and an associated 35-kDa protein (U2AF35). Here we report the isolation of a cDNA encoding U2AF35. U2AF35 contains sequence motifs found in several mammalian pre-mRNA splicing factors. We show directly that U2AF65 and U2AF35 interact with each other and delineate the regions of both proteins that mediate this interaction. Using anti-peptide antibodies against U2AF35, we show that the protein has the intracellular distribution characteristic of U2AF65. Both U2AF65 and U2AF35 are concentrated in a small number of nuclear foci corresponding to coiled bodies, subnuclear organelles first identified by light microscopy in 1903.
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Citation: Proc Natl Acad Sci U S A. 1992 Sep 15;89(18):8769-73.
Proceedings of the National Academy of Sciences of the United States of America
Zhang, Meng; Zamore, Phillip D.; Carmo-Fonseca, Maria; Lamond, Angus I.; and Green, Michael R., "Cloning and intracellular localization of the U2 small nuclear ribonucleoprotein auxiliary factor small subunit" (1992). GSBS Student Publications. 656.