SMAD4 has two functional domains known as MH1 and MH2 .
SMAD4 is a 552 amino - acid polypeptide with a molecular weight of 60.439 Da .
amino - acid polypeptide has two functional domains known as MH1 and MH2 .
SMAD4 is a 552 amino - acid polypeptide with a molecular weight of 60.439 Da .