Vitamin D₃ receptor (VDR) signaling within the mammary gland regulates various postnatal stages of glandular development, including puberty, pregnancy, involution, and tumorigenesis. Previous studies have shown that vitamin D₃ treatment induces cell-autonomous growth inhibition and differentiation of mammary epithelial cells in culture. Furthermore, mammary adipose tissue serves as a depot for ...

The goals of this study were to determine the cellular sites of insulin-like growth factor (IGF) and IGF type-I receptor (IGF-IR) expression and to begin to elucidate functional roles for the IGFs during postnatal development of the murine mammary gland. Using in situ hybridization analyses, we determined that IGF-I, IGF-II, and IGF-IR messenger RNAs were expressed in the highly proliferative t...

The evolution of filter feeding in baleen whales (Mysticeti) facilitated a wide range of ecological diversity and extreme gigantism. The innovation of filter feeding evolved in a shift from a mineralized upper and lower dentition in stem mysticetes to keratinous baleen plates that hang only from the roof of the mouth in extant species, which are all edentulous as adults. While all extant mystic...

Taste buds mature postnatally in the vallate papilla of the rat and reach a mean number of 610 by day 90. Although taste buds are neurotrophically dependent, the presence of widespread bilateral innervation permits more than 80% of the 610 vallate taste buds to survive after one IXth nerve is removed in adults. However, after a IXth nerve is removed at 0-3 d postpartum, about two-thirds of the ...

Elf5 is an epithelial-specific ETS factor. Embryos with a null mutation in the Elf5 gene died before embryonic day 7.5, indicating that Elf5 is essential during mouse embryogenesis. Elf5 is also required for proliferation and differentiation of mouse mammary alveolar epithelial cells during pregnancy and lactation. The loss of one functional allele led to complete developmental arrest of the ma...

In order to elucidate the correlation of temperature and the effect of gibberellin spray on the development of flower-buds in Cryptomeria japonica cultivar Kumotooshi, experiments were done in controlled environmental condition during 1970-1971. The following points were observed: 1. The male flower-buds were formed maximum in the temperature range of 25°C-30°C and their formation decreased wit...

The mouse and rat have been shown to have many taste buds on the incisive papillae of the hard palate. In the rat incisive papilla, taste buds were more numerously observed than in the mouse. They were most densely distributed in both animals on the anteromedial wall of the lower part of the nasopalatine ducts. The taste buds on the mouse incisive papilla appeared at 4 or 5 days of age, and aft...

Sections of tissues containing lingual and extra-lingual taste buds were evaluated with monoclonal antibodies against cytokeratins. In the caudal third of the rat's tongue, keratin 20 immunoreactivity was restricted to taste buds, whereas keratins 7, 8, 18, and 19 were expressed in vallate and foliate taste buds and in cells of salivary ducts that merge with these taste epithelia. Hence, antibo...

close-up, the flower buds of the weed Arabidopsis thaliana appear almost animal-like. The scanning electron micrographs above show a whole inflorescence (top right) and two individual flower buds in detail. The bud of a Columbia wild-type plant shown at bottom right has an oval shape and is tightly closed — as buds normally remain until the anther matures inside. By contrast, the bud on the lef...

Brain-derived neurotrophic factor and neurotrophin-4 are required for normal taste bud development. Although these neurotrophins normally function via the tyrosine kinase receptor, trkB, they also bind to the pan-neurotrophin receptor, p75. The goal of the present study was to determine whether the p75 receptor is required for the development or maintenance of a full complement of adult taste b...