Genomic structure of the mouse gene (Lmnb1) encoding nuclear lamin B1.

The mouse gene (Lmnb1) that encodes nuclear lamin B1 was isolated. Structural analyses revealed that the lamin B1 gene spans about 43 kb of the genome and consists of 11 exons and 10 introns. Exon/intron structure of the B1 gene clearly showed the conserved organization shared among the intermediate filament protein family genes. The presumptive promoter region has high GC content and contains a CAAT box and multiple SP1 sites but no classical TATA box, suggesting that the lamin B1 gene has a typical housekeeping gene promoter with a CpG island. These data reveal the gene structure of the only remaining unanalyzed mouse somatic lamin gene. Gene structures of all the mouse somatic lamins are compared.