Genomic structure and isoform expression of the mouse, rat and human Cbfa1/Osf2 transcription factor.

摘要: Although the CBFA1 gene encodes an osteoblast-specific transcription factor that regulates osteoblast differentiation, uncertainty exists about organization of its 5' end and relevance a novel N-terminal sequence identified in mouse Cbfa1/Osf2 isoform. We found is encoded by previously unrecognized upstream exon, designated exon -1, which highly conserved mouse, rat human. In addition, two splice donor sites may be utilized to generate cDNAs containing different sequences. The first ATG site -1 predicted transcribe cDNA unique Osf2 sequence, whereas second gives rise contain sequences encoding 11 amino acid insert. human gene, additional 2-bp nucleotide insert shifts reading frame results stop codons derived from -1. 5'-most therefore, contains non-coding region rather than OSF2 homolog. absence homologous coding suggests not essential for functioning product. multiple transcripts single CBFA1/Cbfa1 were detected osteoblasts Northern analysis RT-PCR, including isoforms deletions exons 1 4. Thus, alternative use start splicing leads genesis with possible differences transactivation potentials.