Table 2. The structurally conserved motifs of ECD HER2 detected by PROSITE Scan.

Predicted Conserved motifs	Amino Acid Residues	Predicted domain (condition)	Contact region
F1 (L244-K311; PDB sequence number.)	LHCPALVTYNTDTFESMPNPEGRYTFGASCVTACPYNYLSTDVGSCTLVCPLHNQEVTAEDGTQRCEK	Sushi (Disulfide 246C-x-293C and 277C-x-309C)	Heterodimerization region and Pertuzumab binding region.
F2 (N549-E558; PDB sequence number.)	NGSVTCFGPE	NHL	Trastuzumab interacting region.
F3 (D570-E598; PDB sequence number.)	DPPFCVARCPSGVKPDLSYMPIWKFPDEE	ZF-THAP type, degenerate	Trastuzumab interacting region.

The amino acids in bold present involved residues in epitopes of antibodies: trastuzumab and pertuzumab.