NEUROD1 acts in vitro as an upstream regulator of NEUROD2 in trophoblast cells.
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.
Westerman
Bart A
BA
Molecular Biology Laboratory, Department of Clinical Chemistry, VU University Medical Center, de Boelelaan 1117, 1081 HV Amsterdam, The Netherlands.
Chhatta
Aniska
A
Poutsma
Ankie
A
van Vegchel
Thijs
T
Oudejans
Cees B M
CB
D051792:Basic Helix-Loop-Helix Proteins; D045744:Cell Line, Tumor; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000235:genetics*; D024721:E-Box Elements / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology*; D006801:Humans; D066298:In Vitro Techniques; D008156:Luciferases; D009479:Neuropeptides / Q000235:genetics*; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014162:Transfection; D014327:Trophoblasts / Q000502:physiology*
D051792:Basic Helix-Loop-Helix Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; D008156:Luciferases; D009479:Neuropeptides; D015534:Trans-Activators; D014157:Transcription Factors; C065501:ASCL2 protein, human; C489311:Ascl2 protein, mouse; C093970:NEUROD1 protein, human; C490925:NEUROD2 protein, human; C501008:Neurod1 protein, mouse