Project description:The neural crest (NC) is a transient dynamic structure of ectodermal origin, found in early vertebrate embryos. The multipotential NC cells migrate along well defined routes, differentiate to various cells types including melanocytes and participate in the formation of various permanent tissues. Abnormal development of NC cells causes several human diseases M-bM-^@M-^S neurocristopathies. As there is only limited information about the molecular mechanisms controlling early events in melanocyte specification and development, we exploited the AMV v-Myb transcriptional regulator, which directs differentiation of in vitro chicken NC cells to the melanocyte lineage. This activity is strictly dependent on v-Myb specifically binding to the Myb recognition DNA element (MRE). The two tamoxifen-inducible v-myb alleles were constructed, one which recognizes the MRE and one which does not. These were activated in ex-ovo NC cells, and the expression profiles of resulting cells were analyzed using Affymetrix microarrays and RT-PCR. These approaches revealed up-regulation of the BMP antagonist gremlin 2 mRNA, and down-regulation of mRNAs encoding several epithelial genes including KRT19 as very early events following the activation of melanocyte differentiation by v-Myb. Comparison of gene expression profiles of chicken neural crest cells constitutively expressing 4-OH-tamoxifen inducible v-myb with mutated leucine zipper region or a version with an additional point mutation (N118D) in the DNA-binding domain. Three biological replicates were analyzed for each group.
Project description:The neural crest (NC) is a transient dynamic structure of ectodermal origin, found in early vertebrate embryos. The multipotential NC cells migrate along well defined routes, differentiate to various cells types including melanocytes and participate in the formation of various permanent tissues. Abnormal development of NC cells causes several human diseases – neurocristopathies. As there is only limited information about the molecular mechanisms controlling early events in melanocyte specification and development, we exploited the AMV v-Myb transcriptional regulator, which directs differentiation of in vitro chicken NC cells to the melanocyte lineage. This activity is strictly dependent on v-Myb specifically binding to the Myb recognition DNA element (MRE). The two tamoxifen-inducible v-myb alleles were constructed, one which recognizes the MRE and one which does not. These were activated in ex-ovo NC cells, and the expression profiles of resulting cells were analyzed using Affymetrix microarrays and RT-PCR. These approaches revealed up-regulation of the BMP antagonist gremlin 2 mRNA, and down-regulation of mRNAs encoding several epithelial genes including KRT19 as very early events following the activation of melanocyte differentiation by v-Myb.
Project description:INK4A expression in leukemic cells transformed by the v-Myb oncoprotein depends on the integrity of the v-Myb leucine zipper region
Project description:Neural cest cells are a transient stem cell-like population appearing during vertebrate embryonic development. Generation of the cranial neural crest is known to require a balanced combination of FGF and BMP levels. However, it is poorly understood how the functions of such growth factors are controlled in the extracellular spaces. Here we identifiy the extracelluar matrix protein anosmin (Gga.14976.1.S1_at, clone ChEST132d10) as a novel molecule synthesized locally in the cranial neural crest of chicken embryos. Cranial neural folds (NF) and ventral neural plates (NP) were dissected from Hamburger & Hamilton stage 8 (HH8) embryos (80 to 14 embryos, n=4), and total RNA was analyzed using a GeneChip chicken genome arrays (Affymetrix)