Identification and expression analysis of alternative transcripts of the mouse GA-binding protein (Gabp) subunits α and β1

• Published in: Gene 2005, Vol.344, p.79-92
• Main Authors: O'Leary, Debra A., Koleski, Daniela, Kola, Ismail, Hertzog, Paul J., Ristevski, Sika
• Format: Article
• Language: English
• Subjects: 5′ UTR; ETS; GA-binding protein; Polyadenylation signal; Splice variant
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/j.gene.2004.09.031

The erythroblast transformation specific (ETS) transcription factor GA-binding protein (Gabp) is widely expressed and acts on a diverse range of target genes, including nuclear-encoded mitochondrial proteins and neuromuscular-specific genes. The GABPα subunit contains an ETS DNA binding domain and the β subunit contains a nuclear localization signal (NLS) and transactivation domain. Here, we show coincident expression of Gabpα and β 1 throughout mouse embryogenesis, consistent with the gene products functioning in a complex. We have also identified 2 alternatively spliced, tissue-specific exons 1 (5′ untranslated regions) of mouse Gabpα and 4 alternative 3′ polyadenylation signals that, in combination, result in 12 transcripts for Gabpα. These alternative transcripts are suggested to have altered stability, subcellular localization and/or translation efficiency. Further, we identified nine differentially expressed splice variants of mouse Gabpβ 1 that encode β protein forms lacking functional domains, suggesting a dominant negative function. Together, alternative transcripts of Gabpα and β 1 provide a mechanism for tissue-specific regulation of Gabp activity.