Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neuronal basic helix-loop-helix (bHLH) transcription factors such as neuroD and neurogenin have been shown to play important roles in neuronal development. In the present study, several distinct bHLH DNA fragments were isolated from the zebrafish genomic DNA by a pair of degenerate polymerase chain reaction (PCR) primers deduced from the conserved bHLH domains of neuroD and neurogenins. Based on the bHLH fragments, three complete neuroD-related cDNA clones, including complete coding regions, ndr1a, ndr1b, and ndr2 (ndr for neuroD related), were isolated and assembled by 5' and 3' rapid amplification of cDNA ends (RACE). A phylogenetic analysis indicated the presence of four groups of neuroD-related genes in the neuroD subfamily in vertebrates: neuroD, ndr1a/ndr1b/MATH-2, ndr2/NDRF, and neuroM/MATH3. Expression of the newly isolated neuroD-related genes was examined by reverse transcriptase (RT)-PCR and whole-mount in situ hybridization. Unlike neuroD, which was expressed broadly in primary neurons during early zebrafish development starting from 10 h postfertilization (hpf), expression of ndr1a and ndr1b started relatively late (around 22 hpf) and was restricted to the olfactory system: olfactory bulbs in the telecephalon (ndr1a and ndr1b) and olfactory organs (ndr1b) starting around 22 hpf. Although a faint ndr2 mRNA signal was detected by RT-PCR in early embryos, no ndr2 mRNA was detected by whole-mount in situ hybridization in embryos up to 72 hpf, suggesting that it is expressed rather late. Our observations suggest that the two novel neuroD-related genes, ndr1a and ndr1b, are involved in the development of the olfactory system and perhaps contribute to its functional complexity.
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PMID:A class of neuroD-related basic helix-loop-helix transcription factors expressed in developing central nervous system in zebrafish. 1023 16

During early human pregnancy, extravillous trophoblast cells invade the maternal tissue of the uterus in a way similar to invasion by cancer cells. However, the process of trophoblast invasion is regulated in a time and place restricted way, in contrast to cancer invasion. We screened first trimester placental tissue enriched by extravillous invasive trophoblasts for the expression of proneural basic helix-loop-helix (bHLH) transcription factors, which are important controllers of cell fate. Surprisingly, the presence of NEUROD1, NEUROD2 and ATH2 transcripts was found by reverse transcriptase polymerase chain reaction (RT-PCR) analysis in first trimester placentabed. Of these genes, the proneural genes NEUROD1 and NEUROD2 are expressed in different subsets of invasive trophoblasts. NEUROD1 expression is found in interstitial and endovascular invasive cells, while NEUROD2 expression is observed mainly in endovascular invasive cells, respectively. These data suggest that in addition to the involvement of proneural genes in neuron, neurendocrine and pancreas differentiation, these genes are involved in trophoblast differentation during progression of invasion.
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PMID:The proneural genes NEUROD1 and NEUROD2 are expressed during human trophoblast invasion. 1190 Sep 79

The basic helix-loop-helix (bHLH) transcription factors NEUROD1, NEUROD2 and ATH2 are expressed during first trimester human placental development. We determined the transactivation potential of each of these factors in trophoblasts by measuring changes in the endogenous gene activity using absolute quantification by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) after transient transfection. In these assays, NEUROD1 was found to transiently transactivate NEUROD2 in trophoblast cells. Promotor truncation assays, using luciferase constructs, showed the presence of two domains in the NEUROD2 promotor, which showed increased activity after NeuroD1 transfection. Each of these NeuroD1-responsive domains contains an E-box sequence. The NEUROD2 transactivation data fit with the spatial expression pattern of NEUROD1 and NEUROD2, since they are expressed in endovascular trophoblasts. This expression pattern, as well as the present transactivation results, might suggest the presence of a NEUROD differentiation cascade during first trimester human placental development.
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PMID:NEUROD1 acts in vitro as an upstream regulator of NEUROD2 in trophoblast cells. 1473 94