Genomic organization and comparative sequence analysis of the mouse and human FRS2, FRS3 genes.

The signaling adapter proteins FRS2 and FRS3 are implicated in the transmission of extracellular signals from nerve growth factor (NGF) or fibroblast growth factor (FGF) receptors to the Ras/mitogen-activated protein kinase signaling cascade. This study presents the genomic sequence and exon-intron organization of the mouse FRS2 and FRS3 loci as well as their evolutionary conservation with their human counterparts. Both FRS2 and FRS3 contain 5 coding exons spanning over 7 kb of genomic sequence with similar exon sizes and organization. Comparative genomic sequence analyses show a highly conserved genomic organization between mouse and human in both FRS2 and FRS3 genes. Non-coding sequences, highly conserved between mouse and human, were identified in the FRS3 introns that may potentially function as regulatory elements. To assay potential differences in their patterns of expression, RT-PCR analysis was used to assay FRS2 and FRS3 expression in the developing embryo and neural tube (NT) during the time of neurogenesis.