PMC:539061 / 10363-12758
Annnotations
{"target":"https://pubannotation.org/docs/sourcedb/PMC/sourceid/539061","sourcedb":"PMC","sourceid":"539061","source_url":"http://www.ncbi.nlm.nih.gov/pmc/539061","text":"Figure 1 Snail Is Expressed Exclusively in the Hair Bud during Morphogenesis\nEmbryos were either frozen in OCT embedding compound (A, F, and H) or embedded in paraffin (C, D, E, and G), and then sectioned (8 μm).\n(A) In situ hybridizations with Snail sense or antisense cRNA probes. Black dotted lines demarcate the basement membrane that separates the epidermis (epi) from dermis (der). Arrows point to Snail RNA expression, restricted to the hair bud stage of follicle morphogenesis. It was not seen in later hair germ or peg stages.\n(B) Expression of Snail protein coincides with hair development. Protein extracts were prepared from keratinocytes transfected with empty expression vector (K14), containing the K14 promoter or with the vector driving HA-tagged Snail (K14-Snail); or from whole skin from E13.5 to P5 animals, including newborn (nb). Equal amounts of proteins were then resolved by SDS-PAGE through 12% gels and subjected to Western blotting using either an affinity-purified Snail polyclonal antiserum, which we generated, or anti-tubulin (loading control).\n(C–E) Immunohistochemistry shows expression of Snail protein in the nuclei of cells within the hair and skin. (C) E13.5 skin with a single layered epidermis (epi) shows no Snail expression. (D) The first morphological sign that cells have adopted a hair follicle fate is a cluster of cells called a placode in E16.5 skin. Snail is not expressed at this stage of development. (E) Snail is expressed in the hair bud of E17.5 skin but not in later stages of development such as the germ or peg.\n(F) Immunofluorescence with anti-Ki67 (green) identifies the proliferating cells of the skin, restricted to the basal layer of the epidermis and developing hair follicles. Anti-β4 int labeling reveals the presence of the hemidesmosomal integrin β4, restricted to the base of cells adhering to the underlying basement membrane. The white dotted line marks the outermost surface of the skin.\n(G) Immunohistochemistry with pMAPK marks a subset of proliferating cells within the epidermis and hair bud. Anti-pMAPK labeling was consistently robust within the hair bud.\n(H) Immunofluorescence with anti-laminin 5 (lam5), which demarcates the basement membrane, and anti-E-cadherin (E-cad), a component of AJs. At the leading edge of the growing bud, cell-cell borders show markedly diminished anti-E-cadherin labeling (arrowheads).","divisions":[{"label":"label","span":{"begin":0,"end":8}},{"label":"title","span":{"begin":10,"end":77}},{"label":"p","span":{"begin":78,"end":213}},{"label":"p","span":{"begin":214,"end":536}},{"label":"p","span":{"begin":537,"end":1077}},{"label":"p","span":{"begin":1078,"end":1569}},{"label":"p","span":{"begin":1570,"end":1959}},{"label":"p","span":{"begin":1960,"end":2133}}],"tracks":[]}