A Putative Mammalian RNA Helicase with an Arginine-Serine-rich Domain Colocalizes with a Splicing Factor (*)
- From the (1)Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10021
- § To whom correspondence should be addressed: Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, 1230 York Ave., New York, NY 10021. Tel.: 212-327-8896; Fax: 212-327-7880.
Abstract
We have cloned a rat cDNA whose deduced primary structure yields a protein of 117.4 kDa. Because this protein contains RNA helicase consensus motifs, among them a “DEAD” box, we have termed it HEL117 (for helicase of 117.4 kDa). Besides the helicase consensus motifs, HEL117 contains an arginine-serine (RS)-rich domain, which occurs in some proteins involved in RNA splicing. Moreover, the COOH-terminal region of 78 residues of HEL117 is 38.5% identical and 59% similar to the COOH-terminal region of a yeast PRP5 protein that is involved in RNA splicing. Rabbit antibodies generated against a synthetic peptide of HEL117 identified a single polypeptide not only in rat cells but also in cells of other mammals as well as chicken. The antibodies revealed a finely punctate and speckled intranuclear staining in immunofluorescence microscopy. A monoclonal antibody against a human splicing factor containing an RS domain (SC35) showed, in double immunofluorescence microscopy, largely overlapping staining consistent with HEL117 being involved in RNA splicing.
Footnotes
-
↵* The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore by hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
The nucleotide sequence(s) reported in this paper has been submitted to the GenBank
/EMBL Data Bank with accession number(s) U25746.
-
↵1 The abbreviations used are:
- RS domain
-
arginine-serine-rich domain
- PRP
-
pre-mRNA processing
- snRNP
-
small nuclear ribonucleoprotein particle
- kbp
-
kilobase pair(s)
- kb
-
kilobase(s)
- HA
-
hemagglutinin
- PAGE
-
polyacrylamide gel electrophoresis
- FITC
-
fluorescein isothiocyanate.
