Isolation of a vegetalizing inducing factor after extraction with acid ethanol. Concentration-dependent inducing capacity of the factor

Abstract A vegetalizing factor has been isolated from chicken embryos by an improved method. The factor is extracted with acid/ethanol and finally purified by four consecutive steps of reversed phase HPLC. The molecular mass is about 25 kDa. The factor dissociates after reduction with dithiothreitol into two subunits of about 13 kDa. The factor was tested on Triturus alpestris by the implantation method, and on isolated ectoderm of Xenopus laevis in solution. The factor induces as the crude fractions all types of mesodermal tissues dependent on the concentration of the factor.