DNA Dendrimers Localize Myod mRNA in Presomitic Tissues of the Chick Embryo

MyoD expression is thought to be induced in somites in response to factors released by surrounding tissues; however, reverse transcription-PCR and cell culture analyses indicate that myogenic cells are present in the embryo before somite formation. Fluorescently labeled DNA dendrimers were used to identify MyoD expressing cells in presomitic tissues in vivo. Subpopulations of MyoD positive cells were found in the segmental plate, epiblast, mesoderm, and hypoblast. Directly after laying, the epiblast of the two layered embryo contained ∼20 MyoD positive cells. These results demonstrate that dendrimers are precise and sensitive reagents for localizing low levels of mRNA in tissue sections and whole embryos, and that cells with myogenic potential are present in the embryo before the initiation of gastrulation

The Path from New to Viral: Understanding What Makes Videos Go Viral

Viral videos have become very popular and influential in our technology-driven world. They have a strong influence on the production of popular user generated TV shows and websites. Our team explored what makes videos to go viral. We aimed to understand the driving factors behind what makes a video go from one view to thousands of views. We focused particularly on comedic amateur videos that have gone from simply being posted to a social media sites such as YouTube to being aired on popular television programs like Tosh.O and Ridiculousness. We achieved our goal by performing a content analysis of viral videos, conducting a survey to viewers and organizing an interview with a viral video celebrity. Through our research we will present our project background, methodology on collecting data about viral videos, content analysis, and concluding factors in viral armature comedic videos.publishedye

Beta 4 integrin expression in myelinating Schwann cells is polarized, developmentally regulated and axonally dependent

In developing and regenerating peripheral nerve, Schwann cells interact with axons and extracellular matrix in order to ensheath and myelinate axons. Both of these interactions are likely to be mediated by adhesion molecules, including integrins, which mediate cell-cell and cell-extracellular matrix interactions. Recently, the beta 4 integrin subunit was reported to be expressed by Schwann cells in peripheral nerve. We have examined the expression of beta 4, beta 1 and their common heterodimeric partner, the alpha 6 integrin subunit, in developing and regenerating rat peripheral nerve. beta 4 and alpha 6 are enriched in peripheral nerve and they co-localize at the abaxonal surface of myelinating Schwann cells, opposite the Schwann cell basal lamina, which contains possible ligands of alpha 6 beta 4. In contrast, beta 4 and alpha 6 are expressed in a different pattern in non-myelinating Schwann cells. The level of beta 4, but not alpha 6 or beta 1 mRNAs, increases progressively in developing nerves, reaching a peak in adult nerves well after the peak of the myelin-specific mRNAs. After axotomy, the expression of beta 4 mRNA and protein, but not alpha 6 or beta 1 mRNAs, fall rapidly but subsequently are reinduced by regenerating axons. Similarly, in cultured Schwann cells, the expression of beta 4 mRNA, but not alpha 6 mRNA, is significantly modulated by forskolin, a drug that elevates cAMP and mimics some of the effects of axonal contact. beta 4 integrin expression in Schwann cells, therefore, is regulated by Schwann cell-axon interactions, which are known to be critical in determining the Schwann cell phenotype. Furthermore, the polarized expression of alpha 6 beta 4 to the abaxonal surface of myelinating Schwann cells suggests that alpha 6 beta 4 may mediate in part the morphological changes required of Schwann cells in the process of myelination in the peripheral nervous system