FIG. 1.
N-terminal sequences preceding the first cysteine residues of SC3 and its derivatives. In RGD-SC3 the RGD sequence is introduced behind Gly26 and His27 is replaced by serine, creating the GRGDSP sequence of fibronectin. In TrSC3 the amino acids Gly29-Gly53 of SC3 are removed. RGD-TrSC3 is a derivative of TrSC3 in which the RGD sequence is introduced behind Gly26 and His27 is replaced by serine. −M indicates putative O glycosylation sites. The signal sequences that are cleaved off upon entry in the endoplasmic reticulum are indicated in boldface.