In the present work, we proposed to use a new protein–protein docking approach to construct the human CFTR’s NBD1–NBD2 heterodimeric complex based on the crystal structure of human CFTR’s NBD1 and a modeled structure of human CFTR’s NBD2 built
by using NBD1 as a mold. The method requires no a priori knowledge of any dimeric structure of homologous proteins. It also overcomes the potential severe backbone clashing problem in the conventional overlying method. The constructed NBD1–NBD2
model was consistent with the experimentally observed NBD dimers of ABC transporters (see [16] for review). To further validate our model, we docked ATP molecules to the CFTR’s NBD1–NBD2 dimer, and reproduced the observed ATP binding mode in the
NBD1 monomer. Lastly, we used the modeled NBD heterodimer to investigate the interaction between genistein and human CFTR’s NBD dimer by molecular docking. Genistein is an isoflavonoid found in soybeans and soy products that has a prominent effect in
potentiating CFTR channel activity [17–24]. It is regarded as the gold standard for drug screening programs spearheaded by the Cystic Fibrosis Foundation. However, the molecular mechanism of genistein’s activation remains unclear. Based on our computational
results, the putative binding sites of genistein on CFTR were identified, showing consistency with experimental findings.