The mouse neonatal small intestine is regionally specialized for protein absorption and transepithelial transport.

ABSTRACT: In neonates, gastric protein digestion is limited, requiring specialized mechanisms for intestinal protein absorption. While neonatal enterocytes are thought to mediate endocytosis, degradation and transcytosis of dietary proteins, whether these activities are spatially segregated and their molecular basis are unknown. Here, we combine in vivo and ex vivo cargo transport assays with transcriptomic and genetic approaches in mice to uncover distinct roles for jejunal and ileal neonatal enterocytes. We show that the jejunum is highly active in transepithelial transport of intact proteins, whereas the ileum specializes in their lysosomal degradation. Although both regions express similar endocytic receptors, structural and transcriptional analyses uncover divergent endolysosomal programs. Sing

SUBMITTER: Block CL 

PROVIDER: S-EPMC12746077 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature