Gene transfer could provide a novel therapeutic approach for cystic fibrosis (CF), and adeno-associated virus (AAV) is a promising vector. However, the packaging capacity of AAV limits inclusion of the full-length cystic fibrosis transmembrane conductance regulator (CFTR) cDNA together with other regulatory and structural elements. To overcome AAV size constraints, we recently developed a shortened CFTR missing the N-terminal portion of the R domain (residues 708–759, CFTRΔR) and found that it retained regulated anion channel activity in vitro. To test the hypothesis that CFTRΔR could correct in vivo defects, we generated
CFTR
−/−
mice bearing a transgene with a fatty acid binding protein promoter driving expression of human CFTRΔR in the intestine (
CFTR
−/−
;TgΔR
). We found that intestinal crypts of
CFTR
−/−
;TgΔR
mice expressed CFTRΔR and the intestine appeared histologically similar to that of WT mice. Moreover, like full-length
CFTR
transgene, the
CFTRΔR
transgene produced CFTR Cl
−
currents and rescued the
CFTR
−/−
intestinal phenotype. These results indicate that the N-terminal part of the CFTR R domain is dispensable for in vivo intestinal physiology. Thus, CFTRΔR may have utility for AAV-mediated gene transfer in CF.