Experimental evidence for RNA trans‐splicing in mammalian cells

• Published in: The EMBO journal 1995-07, Vol.14 (13), p.3226-3235
• Main Authors: Eul, J., Graessmann, M., Graessmann, A.
• Format: Article
• Language: English
• Subjects: Alternative Splicing; Amino Acid Sequence; Animals; Antigens, Viral, Tumor - biosynthesis; Antigens, Viral, Tumor - chemistry; Antigens, Viral, Tumor - genetics; Base Sequence; Cells, Cultured; Exons; Gene Expression Regulation, Viral; HeLa Cells; Humans; Introns; Mammals - genetics; Models, Genetic; Molecular Sequence Data; Rats; RNA - biosynthesis; RNA - chemistry; RNA - genetics; RNA Processing, Post-Transcriptional; RNA, Messenger - biosynthesis; RNA, Messenger - chemistry; RNA, Messenger - genetics; RNA, Viral - chemistry; RNA, Viral - genetics
• ISSN: 0261-4189; 1460-2075
• DOI: 10.1002/j.1460-2075.1995.tb07325.x

We present evidence that mammalian cells have the ability to generate functional mRNA molecules by trans‐splicing. Rat cells, transformed by an early SV40 DNA fragment (Bst/Bam) synthesize a truncated T antigen (T1 antigen), although the cells do not have a direct sequence homology for the T1 antigen at the DNA level. The Bst/Bam DNA fragment encodes exclusively for the second SV40 T antigen exon (aa 83‐708) and contains the entire small t antigen intron. To synthesize the corresponding mRNA (T1 mRNA), the cells utilize a cryptic 5′ splice site within the second exon (codons for aa 131/132) as donor site and the upstream small t antigen 3′ splice site as the acceptor site. Since these sites are in an inverted order on the pre‐mRNA, two Bst/Bam transcripts are required to generate one T1 mRNA molecule. HeLa cell nuclear extracts also performed the trans‐splicing reaction in vitro.