Activation of dynamin I gene expression by Sp1 and Sp3 is required for neuronal differentiation of N1E-115 cells.
Dynamin I is a key molecule required for the recycling of synaptic vesicles in neurons, and it has been known that dynamin I gene expression is induced during neuronal differentiation. Our previous studies established that neuronal restriction of dynamin I gene expression is controlled by Sp1 and nuclear factor-kappaB-like element-1. Here, using a series of deletion constructs and site-directed mutation, we found that transcription of dynamin I gene during neuronal differentiation of N1E-115 cells is controlled primarily by the Sp1 element located between -13 to -4 bp of the dynamin I promoter. Gel shift analysis demonstrated that in addition to Sp1, Sp3 could interact with this Sp1 element. The requirement for Sp family transcription factors in dynamin I gene expression was confirmed by using mithramycin, an inhibitor of Sp1/Sp3 binding. Mithramycin repressed dynamin I gene expression and resulted in blocking of neuronal differentiation of N1E-115 cells. The localization of the dynamin I protein was also restricted in the peripheral region of the nucleus by the mithramycin treatment. Thus, all of our results suggest that induction of dynamin I gene expression during N1E-115 cell differentiation is modulated by Sp1/Sp3 interactions with the dynamin I promoter, and its expression is important for neuronal differentiation of the N1E-115 cells.
Yoo
Jiyun
J
Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Taejon 305-600, Korea.
Jeong
Moon-Jin
MJ
Kwon
Byoung-Mog
BM
Hur
Man-Wook
MW
Park
Young-Mee
YM
Han
Mi Young
MY
D000818:Animals; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D015500:Chloramphenicol O-Acetyltransferase / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D034284:Dynamin I; D034281:Dynamins; D020558:GTP Phosphohydrolases / Q000096:biosynthesis* / Q000235:genetics*; D017353:Gene Deletion; D051379:Mice; D018613:Microscopy, Confocal; D016297:Mutagenesis, Site-Directed; D016328:NF-kappa B / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D010957:Plasmids / Q000378:metabolism; D008926:Plicamycin / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D051705:Sp3 Transcription Factor; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D014162:Transfection; D014407:Tumor Cells, Cultured; D001616:beta-Galactosidase / Q000378:metabolism
D004268:DNA-Binding Proteins; D016328:NF-kappa B; D011500:Protein Synthesis Inhibitors; D016329:Sp1 Transcription Factor; C497122:Sp3 protein, mouse; D014157:Transcription Factors; D051705:Sp3 Transcription Factor; D015500:Chloramphenicol O-Acetyltransferase; D001616:beta-Galactosidase; D034284:Dynamin I; D020558:GTP Phosphohydrolases; D034281:Dynamins; D008926:Plicamycin