Fig. 1: Rnase4 is expressed in intestinal epithelium and detected in stool samples.

a, b Rnase4 expression levels in different intestinal cell types based on single-cell RNA sequencing data, sourced from Mouse Cell Atlas (bis.zju.edu.cn/MCA) and Human Protein Atlas (www.proteinatlas.org). c Rnase4 expression levels in different mouse intestinal epithelial cell types by quantitative PCR (n = 3 mice). ISC intestinal stem cell, TA transit-amplifying. d, e Rnase4 localization in small and large intestines of WT and Rnase4^−/− mice, and intestinal organoids cultured from WT by immunofluorescence staining. The nuclei were stained with Hoechst 33342. The white arrows indicate the localization of Rnase4 in secretory, granule-like structure of goblet and Paneth cells. Scale bar, 25 μm. f Rnase4 protein levels in colon, mucus layer, and stool sample of WT and Rnase4^−/− mice by immunoblotting. Coomassie blue staining shows the total protein loading amount. g RNASE4 localization in human small and large intestines by immunofluorescence staining. The nuclei were stained with Hoechst 33342. The white arrows indicate the localization of RNASE4 in secretory, granule-like structure of goblet and Paneth cells. Scale bar, 25 μm. h RNASE4 protein levels in three human stool samples by immunoblotting. Coomassie blue staining shows the total protein loading amount. Data are presented as mean ± SEM (c). Representative images from three independent experiments are shown (d, e and g).