Journal: International Journal of Molecular Sciences
Article Title: Distinct and Overlapping Expression Patterns of the Homer Family of Scaffolding Proteins and Their Encoding Genes in Developing Murine Cephalic Tissues
doi: 10.3390/ijms21041264
Figure Lengend Snippet: Expression patterns of Homer1, Homer2 and Homer3 during advanced stages of tooth formation. ( A – R ) Representative in situ hybridization ( A – C , G – I ) and immunohistochemistry ( D – F , J – R ) data showing the distribution patterns of Homer1 ( A , G ), Homer2 ( B , H ) and Homer3 ( C , I ) transcripts (brown) and Homer1 ( D , J , M , P ), Homer2 ( E , K , N , Q ) and Homer3 ( F , L , O , R ) proteins (purple) in developing teeth at 12 days postpartum (12 dpp). ( A – F ) Sections across incisors at the level of the secretory stage of enamel formation. Secretory ameloblasts and young odontoblasts (cells facing a thin layer of predentin/dentin matrices) express the three Homer proteins and their encoding genes. The asterisks in ( D , F ) mark an artefactual space due to detachment of secretory ameloblasts from dentin. ( G – L ) Sections at the level of enamel maturation showing expression of the three Homer proteins and their encoding genes in maturation-stage ameloblasts and in the papillary layer. ( M – R ) Sections across molars showing expression of Homer proteins in mature odontoblasts (cells that have produced a thick layer of predentin/dentin) ( M – O ) and in Hertwig’s epithelial root sheath ( P – R ). Secretory ameloblasts, maturation-stage ameloblasts, odontoblasts and cells of the papillary layer exhibit puncta enriched with Homer proteins ( D – F , J – O ). Note that the Homer-positive(+) puncta in young odontoblasts ( D – F ) are less prominent than the Homer+ puncta in mature odontoblasts ( M – O ) and that the Homer3+ puncta in subsets of cells of the dental pulp are apparently smaller than the Homer3+ puncta in mature odontoblasts ( O ). Odontoblasts in the developing roots express Homer proteins ( P – R ). The endothelium of vascular loops penetrating the papillary layer ( I , L ) and of blood vessels in the dental pulp and dental sac mesenchyme ( C , F , I , L , O , R ) expresses Homer3 mRNA and protein and exhibits weak Homer1 ( D , J , M , P ) and moderate Homer2 ( E , K , N , Q ) immunostaining. BV, blood vessels; DS, dental sac; HS, Hertwig’s epithelial root sheath; MA, maturation-stage ameloblasts; Od, odontoblasts; P, dental pulp; PD/D, predentin/dentin matrices; PL, papillary layer; SA, secretory ameloblasts; SI, stratum intermedium. Scale bars: 50 µm ( A – R ).
Article Snippet: The affinity-purified rabbit anti-Homer2 (product No. NBP1-85487) and the affinity-purified rabbit anti-Homer3 (product No. NBP2-32607) were from Novus Biologicals (Abingdon, UK).
Techniques: Expressing, In Situ Hybridization, Immunohistochemistry, Produced, Immunostaining