Identification of new human coding steroid receptor RNA activator isoforms.
SRA is a steroid receptor co-activator which acts as a functional RNA and is classified as belonging to the growing family of functional non-coding RNAs. None of the different SRA transcripts described to date encode a detectable SRA protein following in vitro and in vivo translation experiments. We have identified three new SRA-RNA isoforms differing mainly from the originally cloned SRA by an extended 5(') extremity. These long SRA isoforms, able to encode a stable protein in vitro, led to the production in vivo of a nuclear protein when transfected into the MCF-7 human breast cancer cell line. Reverse-transcription polymerase chain reaction and Western blot analysis of RNA and protein extracts from different breast cancer cell lines confirmed the presence of endogenous coding SRA isoforms and their corresponding proteins. Our results demonstrate that full-length SRA-RNAs likely to encode stable proteins are widely expressed in breast cancer cell lines.
Emberley
Ethan
E
Department of Biochemistry and Medical Genetics, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada R3EOW3.
Huang
Guo-Jian
GJ
Hamedani
Mohammad K
MK
Czosnek
Anna
A
Ali
Djiae
D
Grolla
Allen
A
Lu
Biao
B
Watson
Peter H
PH
Murphy
Leigh C
LC
Leygue
Etienne
E
D024506:5' Flanking Region; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001943:Breast Neoplasms; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012313:RNA / Q000235:genetics; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D016415:Sequence Alignment; D014407:Tumor Cells, Cultured
D020033:Protein Isoforms; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; C405423:steroid receptor RNA activator; D012313:RNA