16S rRNA gene sequences amplified from the skin of WT and resistin-like molecule (RELM) alpha deficient mice. mouse skin metagenome

Vitamin A deficiency increases susceptibility to skin infection yet how vitamin A regulates skin immunity remains unclear. Here, we show that resistin-like molecule alpha (RELMa) is a skin antimicrobial protein that is required for vitamin A-dependent resistance to skin infection. RELMa was induced in mouse skin by bacterial colonization, killed skin bacteria in vitro, and protected against bacterial infection of the skin in vivo. The 16S small subunit ribosomal (rRNA) gene is present in every bacterial cell, serving as a universal marker. The gene is sufficiently conserved to allow accurate alignment but adequately varied to enable phylogenetic analyses. We examined the bacterial diversity of skin in the presence/absence of RELMa using a 16S rRNA survey