RRC ID 38201
Author Yamaguchi K, Koseki K, Shiozaki M, Shimada Y, Wada T, Miyagi T.
Title Regulation of plasma-membrane-associated sialidase NEU3 gene by Sp1/Sp3 transcription factors.
Journal Biochem J
Abstract Gene expression of the human plasma membrane-associated sialidase (NEU3), a key enzyme for ganglioside degradation, is relatively high in brain and is modulated in response to many cellular processes, including neuronal cell differentiation and tumorigenesis. We demonstrated previously that NEU3 is markedly up-regulated in various human cancers and showed that NEU3 transgenic mice developed a diabetic phenotype and were susceptible to azoxymethane-induced aberrant crypt foci in their colon tissues. These results suggest that appropriate control of NEU3 gene expression is required for homoeostasis of cellular functions. To gain insights into regulation mechanisms, we determined the gene structure and assessed transcription factor involvement. Oligo-capping analysis indicated the existence of alternative promoters for the NEU3 gene. Transcription started from two clusters of multiple TSSs (transcription start sites); one cluster is preferentially utilized in brain and another in other tissues and cells. Luciferase reporter assays showed further that the region neighbouring the two clusters has promoter activity in the human cell lines analysed. The promoter lacks TATA, but contains CCAAT and CAAC, elements, whose deletions led to a decrease in promoter activity. Electrophoretic mobility-shift assays and chromatin immunoprecipitation demonstrated binding of transcription factors Sp (specificity protein) 1 and Sp3 to the promoter region. Down-regulation of the factors by siRNAs (short interfering RNAs) increased transcription from brain-type TSSs and decreased transcription from other TSSs, suggesting a role for Sp1 and Sp3 in selection of the TSSs. These results indicate that NEU3 expression is diversely regulated by Sp1/Sp3 transcription factors binding to alternative promoters, which might account for multiple modulation of gene expression.
Volume 430(1)
Pages 107-17
Published 2010-8-15
DOI 10.1042/BJ20100350
PII BJ20100350
PMID 20518744
MeSH Cell Line Cell Membrane / metabolism* Exons Gene Expression Regulation, Enzymologic Humans Introns Neuraminidase / biosynthesis* Neuraminidase / genetics Promoter Regions, Genetic Sp1 Transcription Factor / physiology* Sp3 Transcription Factor / physiology* Transcription Initiation Site
IF 4.097
Times Cited 16
WOS Category BIOCHEMISTRY & MOLECULAR BIOLOGY
Resource
Human and Animal Cells 293(RCB1637)