BETACELLULIN MUTEIN

摘要

Disclosed is a betacellulin mutein which is a stable protein, has low antigenicity, retains an activity of causing the differentiation of an undifferentiated pancreatic stem cell into an islet beta-cell, and has a reduced cell proliferation activity. Specifically disclosed is a betacellulin mutein having an amino acid sequence corresponding to an amino acid sequence lying between position-38 and position-62 in the amino acid sequence depicted in SEQ ID NO:1 (provided that Glu at position-57 is substituted by a basic or aromatic amino acid residue, and the amino acid sequence corresponding to an amino acid sequence lying between position-38 and position-50 may have the substitution, insertion and/or deletion of one or more amino acid residues).