It has also been demonstrated that FgfR1 regulates blastemal cell proliferation during fin regeneration.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

In particular, FgfR1 is expressed in pre-blastema mesenchymal cells during blastema formation, and maintained in subpopulations of blastemal and epidermal cells during outgrowth.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference