Cloning of mouse FGF10 and up-regulation of its gene expression during wound healing

We cloned the mouse homolog of FGF10, which was recently reported as a new member of the FGF family. The predicted molecular mass of this molecule is 23.6 kDa, and both nucleotide and amino acid sequences show high degrees of similarity with those of the rat. Examination of mouse FGF10 mRNA expression in various tissues and developmental stages by Northern hybridization revealed tissue- and developmental stage-specific expression of the gene. Similarly to the rat counterpart, mouse FGF10 mRNA (4.5 kb) was expressed relatively abundantly in embryos and the lung, and at much lower levels in brain and heart. In addition, a shorter transcript (1.3 kb) is expressed only in testis. Considering the high similarity in primary structure between FGF10 and FGF7 (known as keratinocyte growth factor; KGF), we also examined the gene expression of FGF10 during wound healing using a mouse model. FGF10 mRNA was highly induced 1 day after injury and decreased rapidly by 3 days. This suggests that FGF10 is a primary factor in the process of wound healing similarly to other growth factors such as TGF alpha and FGF7.