BEST2 and colitis: Since BEST2 gene knockout mice spontaneously develop colitis (21), the mechanism of action of BEST2 in cases of UC may be similar to that of other ion channels (such as NHE1 and NHE3) (22, 23), with high activation of the Notch signalling pathway inhibiting the expression of BEST2, which may be one of the mechanisms underlying UC pathogenesis (Figure 2).