Home  About us  Contact
 

Enhancer Regions (enhancer + regions)

Distribution by Scientific Domains
Life Sciences75%

Selected Abstracts

Functional analysis of synaptotagmin gene regulatory regions in two distantly related ascidian species

DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 7 2008
Jun Matsumoto
We have studied the structure and function of a promoter region of the Halocynthia synaptotagmin (Hr-Syt) gene, which is abundantly expressed in neuronal cells. Our previous analysis suggested that the expression of Hr-Syt is regulated by at least one epidermal and two neuronal regulatory regions. In this study, the regulatory regions of Hr-Syt promoter were further characterized by using two species of ascidians, Halocynthia roretzi and Ciona intestinalis embryos. A putative GATA transcription factor binding site in the epidermal regulatory region has ectodermal enhancer activity in the Halocynthia embryo. Neuronal expression of Hr-Syt was regulated by multiple redundant enhancer regions. Among these enhancer regions, a 200-bp (,2900/,2700) region drove the reporter expression in neurons in both species of ascidian. Although the synaptotagmin promoter sequences did not show overall similarity between Hr-Syt and Ciona synaptotagmin (Ci-Syt), 5,-upsteream two short sequences of Ci-Syt have similarity to the ,2766/,2732 region of the Hr-Syt promoter. The homeodomain binding sites in this region are required for the neuronal enhancer activity. These results suggest that GATA and homeodomain transcription factors regulate the expression of synaptotagmin. [source]

piggyBac -mediated germline transformation in the beetle Tribolium castaneum

INSECT MOLECULAR BIOLOGY, Issue 5 2003
M. D. Lorenzen
Abstract The lepidopteran transposable element piggyBac can mediate germline insertions in at least four insect orders. It therefore shows promise as a broad-spectrum transformation vector, but applications such as enhancer trapping and transposon-tag mutagenesis are still lacking. We created, cloned, sequenced and genetically mapped a set of piggyBac insertions in the red flour beetle, Tribolium castaneum. Transpositions were precise, and specifically targeted the canonical TTAA recognition sequence. We detected several novel reporter-expression domains, indicating that piggyBac could be used to identify enhancer regions. We also demonstrated that a primary insertion of a non-autonomous element can be efficiently remobilized to non-homologous chromosomes by injection of an immobile helper element into embryos harbouring the primary insertion. These developments suggest potential for more sophisticated methods of piggyBac -mediated genome manipulation. [source]

NF-,B activation in development and progression of cancer

CANCER SCIENCE, Issue 3 2007
Jun-ichiro Inoue
Nuclear factor-,, (NF-,B) binds specifically to NF-,B-binding sites (,B sites, 5,-GGGRNNYYCC-3,; R, purine; Y, pyrimidine; N, any nucleotide) present in enhancer regions of various genes. Binding of various cytokines, growth factors and pathogen-associated molecular patterns to specific receptors activates NF-,B and expression of genes that play critical roles in inflammation, innate and acquired immunity, bone remodeling and generation of skin appendices. Activation of NF-,B is also involved in cancer development and progression. NF-,B is activated in cells that become malignant tumors and in cells that are recruited to and constitute the tumor microenvironment. In the latter scenario, the TLR-TRAF6-NF-kB pathways seem to play major roles, and NF-,B activation results in production of cytokines, which in turn induce NF-,B activation in premalignant cells, leading to expression of genes involved abnormal growth and malignancy. Furthermore, NF-,B activation is involved in bone metastasis. Osteoclasts, whose generation requires the RANK-TRAF6-NF-,B pathways, release various growth factors stored in bone, which results in creation of microenvironment suitable for proliferation and colonization of cancer cells. Therefore, NF-,B and molecules involved its activation, such as TRAF6, are attractive targets for therapeutic strategies against cancer. (Cancer Sci 2007; 98: 268,274) [source]