The function of KRT13 (keratin 13, ENSG00000171401) is as follows. Structural component of intermediate filaments in mucosal stratified squamous epithelia. Forms heteropolymers with the type II keratin KRT4, assembling into keratin intermediate filament networks that provides structural integrity and mechanical stability of the mucosal epithelium (PubMed:7493031). Contributes to postnatal tongue mucosal cell homeostasis and tissue organization in response to mechanical stress, potentially through regulation of the G1/S phase cyclins CCNE1 and CCNE2 (By similarity). {ECO:0000250|UniProtKB:P08730, ECO:0000269|PubMed:7493031}.