Conservation and expression of an alternative 3′ exon of Runx2 encoding a novel proline-rich C-terminal domain

Abstract

The Runx2 (Cbfa1, Aml3, PEBP2αA) gene plays an essential role in bone development and is one of a three-member family of closely related genes that encode the α-chain DNA binding components of the heterodimeric core binding factor complex. While all three mammalian Runx genes share a complex dual promoter structure (P1, P2) and display alternative splicing, a distinctive feature of Runx2 is the potential to encode larger isoforms in which the C-terminal domain encoded by the standard 3′ terminal exon (exon 6) is replaced by an extended 200-201 amino acid C-terminal sequence including an extensive proline-rich domain and a C-terminal amphipathic helix. We report that the novel exon that gives..