The expression of the human neuronal alpha3 Na+,K+-ATPase subunit gene is regulated by the activity of the Sp1 and NF-Y transcription factors.
The Na+,K+-ATPase is a ubiquitous protein found in virtually all animal cells which is involved in maintaining the electrochemical gradient across the plasma membrane. It is a multimeric enzyme consisting of alpha, beta and gamma subunits that may be present as different isoforms, each of which has a tissue-specific expression profile. The expression of the Na+,K+-ATPase alpha3 subunit in humans is confined to developing and adult brain and heart, thus suggesting that its catalytic activity is strictly required in excitable tissues. In the present study, we used structural, biochemical and functional criteria to analyse the transcriptional mechanisms controlling the expression of the human gene in neurons, and identified a minimal promoter region of approx. 100 bp upstream of the major transcription start site which is capable of preferentially driving the expression of a reporter gene in human neuronal cell lines. This region contains the cognate DNA sites for the transcription factors Sp1/3/4 (transcription factors 1/3/4 purified from Sephacryl and phosphocellulose columns), NF-Y (nuclear factor-Y) and a half CRE (cAMP-response element)-like element that binds a still unknown protein. Although the expression of these factors is not tissue-specific, co-operative functional interactions among them are required to direct the activity of the promoter predominantly in neuronal cells.
Department of Pharmacology, School of Medicine, University of Milan, 32 via Vanvitelli, 20129 Milan, Italy.
Roberta
R
Benfante
Ruth Adele
RA
Antonini
Monica
M
Vaccari
Adriano
A
Flora
Fabian
F
Chen
Francesco
F
Clementi
Diego
D
Fornasari
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D023081:CCAAT-Binding Factor / Q000502:physiology*; D045744:Cell Line, Tumor / Q000201:enzymology; D017362:Cyclic AMP Response Element-Binding Protein; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000502:physiology*; D004790:Enzyme Induction; D005326:Fetal Proteins / Q000096:biosynthesis / Q000235:genetics; D020869:Gene Expression Profiling; D017930:Genes, Reporter; D006367:HeLa Cells / Q000201:enzymology; D006801:Humans; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics*; D009447:Neuroblastoma / Q000473:pathology; D009474:Neurons / Q000201:enzymology*; D020411:Oligonucleotide Array Sequence Analysis; D009928:Organ Specificity; D011401:Promoter Regions, Genetic / Q000235:genetics; D021122:Protein Subunits; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012045:Regulatory Sequences, Nucleic Acid; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D000254:Sodium-Potassium-Exchanging ATPase / Q000096:biosynthesis / Q000235:genetics*; D016329:Sp1 Transcription Factor / Q000502:physiology*; D013045:Species Specificity; D014157:Transcription Factors / Q000502:physiology*; D014158:Transcription, Genetic; D014162:Transfection
C488756:ATP1A3 protein, human; D023081:CCAAT-Binding Factor; C115163:CREB1 protein, human; D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D005326:Fetal Proteins; C492063:NFYB protein, human; D009419:Nerve Tissue Proteins; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D000254:Sodium-Potassium-Exchanging ATPase