| Glial cells can be activated by dopamine and the activated glial cells appear to play a protective role for DA-innervated neurons. To investigate the potential mechanism of activated glial cells by DA and find DA responsive genes, the suppression subtractive hybridization (SSH) and homologous cloning were applied to isolate and identify the DA responsive genes from glial cells. Dopamine-associated transcription (DAT1, GenBank#AF258348) is one of these genes that are up-regulated in activated glial by DA.DAT1, a LIM-only(LMO) gene, which is composed of two tandem LIM domain and little other sequence. The LIM domain defines a conserved cysteine-rich structure comprising two tandemly repeated zinc fingers.Prevailing evidence support the notion that LIM proteins have critical function in development , differentiation and regulation of cytoskeleton dynamics in diverse systems because the LIM domain can act as a protein -protein interaction adapter.LIM proteins can be divided into four groups. LIM homeodomain (LIM-HD) proteins, one group of LIM proteins, can bind with DNA and play importment role in cell fate decisions and organ development. LMO proteins have more important role in development than the LIM-HD proteins and they have also been shown to be involved in oncogenesis. LMO proteins comprise 4 members. The LMO1 and LMO2 were discovered by virtue of their translocation in acute T cell lymphocytic leukemia (T-ALL) and their expression level is positive correlation with cancer's malignancy. LMO2 is essential for embryonic hematopoiesis and is thought to function at the level of the pluripotent stem cell. Expression of the LMO4 gene is developmentally regulated in the mammary gland and is up-regulated in primary breast cancers. A multiprotein complex involving LMO4, CtEP, and BRCA1 could be demonstrated in vivo.LMO4 was found to be a repressor of BRCA1-mediated transcriptional activity, resulting in breast cancers. Rescently a study shows that LMO4 interactes with Deaf-1 and has an important role for these two transcriptional regulators in pathways affecting neural tube closure. Researchers have carried out gene targeting of the LIM-only family, viz., genes Lmol, Lmo3 and Lmo4, to investigate their role in mousedevelopment. The results show that the null mice appear different phenotype by virtue of different gene null. It indicates that the three members of this family are important regulators of distinct developmental pathways.In order to assess the function of DAT1, In Situ Hybridization, RT-PCR, real-time fluorescence quantitative RT-PCR(FQ RT-PCR), NSCs transfection and yeast hybrid system methods were used to find out the developmental expression of DAT1, the effect on NSCs and its interaction cofactor. It helps us not only to comprehend the role of DAT1 in CNS, but also to understand the effect of DAT 1 in oncogenesis of CNS and other degenerative disease.1. Using bioinformatics analysis, we found that homologous EST and SAGE tag of DAT1 mainly distribute in fetal brain, brain, glioma, lung and carcinoid of lung. RT-PCR showed that DAT1 expressed in mice brain, human glioma cells and neuroblastoma cells, but not detected in other mice tissue and glial cells (C8 cells). The overexpression of DAT1 in C8 could facilitate cell proliferation of glial cells.Using in situ hybridization histochemistry staining method we found that the transcripts of DAT1 mRNA were localized in somatic and dendritic profiles at most regions of adult rat and mice central nervous system. It observed in cerebrum, cerebellum, thalamus, brain stem and spine. The intense hybridization signal can be seen in olfactory bulb, entorhinal cortex, prepirform cortex, striate cortex, hippocampus CA1 and dentate gyrus, red nucleus, motor nucleus of trigemina, nucleus of hypoglossal, para ventricular nucleus, substantia nigra. The moderate staining was detected in central gray, spinal cord gray matter, bed nucleus of the stria terminalis, preoptic region. The weak signals were detected in some nucleus of thalamus and cereb...
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