(A) Graphical representation of Esrp1 (blue) and Esrp2 (red) expression in mouse tissues and cells (BioGPS) (Su et al., 2002). Relatively overlapping expression patterns for Esrp1 and Esrp2, except in the Liver where Esrp2 is expressed and Esrp1 is not. (B) (Panel A) Array of whole-body sections with e10.5 (#1–#3), e12.5 (#4 and #5), e15.5 (#6 and #7) and postnatal (#8 and #9) mice following staining with cresyl violet. (Panel B) X-ray film autoradiography detection of Esrp2 mRNA, seen as bright labeling. The labeling is clearly detectable at stage e15.5 in the skin. Pronounced signal is detectable in postnatal mice skin, olfactory neuroepithelium, esophagus, stomach and rectum. Moderate labeling is seen in submaxillary gland, liver, lung and kidney. (Panel C) Control (sense) hybridization in an adjacent section comparable to (panel B). (C) (Panel A) Whole-body sections of adult mouse (male) following staining with cresyl violet. (Panel B) X-ray film autoradiography detection of Esrp2 mRNA. The expression pattern encompasses skin, stomach, intestine and gut-associated salivary glands and liver. In the stomach, Esrp2 is expressed in glandular epithelium, but not in non-glandular epithelium. Non-specific labeling is seen in bone (*) and thymus (**). (Panel C) Control (sense) hybridization. Abbreviations: AT—adipose tissue; Br—brain; C—colon; Es—esophagus; H—heart; K—kidney; Li—liver; Lu—lung; Mu—skeletal muscles; NC—nasal chamber; ONE—olfactory neuroepithelium; Pa—pancreas; R(embryo)/Re(adult)—rectum; Re (embryo)—retina; Sm—submaxillary gland; St—stomach; Tc—telencephalon; Th—thymus; UB—urinary bladder; (as)—antisense; (s)—sense (Magnification: 2.4×). (D) Digoxigenin-UTP-labeled in situ hybridization of Esrp1 in P0 epidermis of WT (Esrp1+/+, Esrp2+/+) and KO (Esrp1−/−, Esrp2+/+). Esrp1 expression in restricted to the basal keratinocyte (including epithelial cells of the hair follicle) to the granular layer of the epidermis, and absence of signal in the Esrp1 KO epidermis. E: Epidermis, D: Dermis, HF: Hair follicle. (E) Expression of Esrp1 and Esrp2 from published microarrays. Esrp1 and Esrp2 are enriched in the epithelial compartments of the skin and associated appendages: Epidermis, Matrix, Outer Root Sheath (ORS), Bulge cells, and Hair Germ (HG) while absent in the non-epithelial cells: Dermis, Dermal Papilla (DP), and Melanocytes. Graphs from left to right: (Zhang et al., 2008, GSE10773), (Rendl et al., 2005, GSE3142), and (Greco et al. 2009, GSE15185) represent Esrp1 and Esrp2 expression from publically available microarray data.