MAPK3 and gastroenteritis: These Ecsitfl/flVillin‐Cre‐ERT2 mice (cKO) also showed spontaneous intestinal inflammation that was associated with weight loss (Figure 1D), shortening of the colon (Figure S4A, Supporting Information), intestinal structure disorders (Figure 1E and Figure S4B, Supporting Information), increased infiltration of inflammatory cells (Figure 1F), and increased serum inflammatory cytokines (Figure 1G).