I am new to protein modeling. I need to model a homodimer for full length human Foxp3 (Uniprot Id B7ZLG1) which is 454 amino acids long. Two templates are available in PDB: 3QRF and 4I1L. They represent small and non-overlapping regions of the sequence. Can I model the homodimer for the entire sequence? Can I also identify those residues which are involved in dimer formation? What tools can I use to model the homodimer and validate the model?