Abstract
Transcription regulatory elements have been analyzed in upstream sequences of an Interleukin-6 (Il-6) primary response gene, MyD88. MyD88 2.3 kb mRNA is strongly and persistently induced in the course of myeloleukemic M1 cells differentiation with Il-6. MyD88 cDNA sequences were found in a region of 12 kb of mouse genomic DNA. Using Il-6 treated M1 cell RNAs, two transcription start sites have been localized, approximately 100 bp upstream from the 5' end of the cloned cDNA. We sequenced 1.4 kb of 5' genomic DNA including the first exon. In 5' of mRNA transcription start site, MyD88 nucleotidic sequence is 85% identical to 5' complementary sequences of the rat 3'-ketoacetyl CoA thiolase gene, over 1.2 kb. A DNA element conferring Il-6-inducible transcription to reporter genes, and localized 30 bp upstream of MyD88 first RNA start site, contains overlapping binding sites for cytokine activated transcription factors Stat and for the Interferon Regulatory Factor-1 and -2 (IRF-1 and IRF-2). In vitro binding assays showed that attachment of Stat factors to this element early in Il-6 treatment requires tyrosine kinase activation. IRF1, an activator of transcription, is also induced to bind to this sequence at later times. A model of persistent activation of MyD88 gene through these two types of factors is proposed.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Adaptor Proteins, Signal Transducing
-
Animals
-
Antigens, Differentiation*
-
Base Sequence
-
Cloning, Molecular
-
DNA-Binding Proteins / metabolism*
-
Gene Expression Regulation / drug effects
-
Genes
-
Genes, Immediate-Early
-
Humans
-
Immediate-Early Proteins / genetics*
-
In Vitro Techniques
-
Interferon Regulatory Factor-1
-
Interferon Regulatory Factor-2
-
Interleukin-6 / pharmacology*
-
Mice
-
Molecular Sequence Data
-
Myeloid Differentiation Factor 88
-
Phosphoproteins / metabolism
-
Promoter Regions, Genetic*
-
Proteins / genetics*
-
RNA, Messenger / genetics
-
Receptors, Immunologic*
-
Regulatory Sequences, Nucleic Acid
-
Repressor Proteins*
-
STAT1 Transcription Factor
-
STAT3 Transcription Factor
-
Trans-Activators / metabolism
-
Transcription Factors / metabolism*
-
Transcription, Genetic / drug effects
-
Tumor Cells, Cultured
Substances
-
Adaptor Proteins, Signal Transducing
-
Antigens, Differentiation
-
DNA-Binding Proteins
-
IRF1 protein, human
-
IRF2 protein, human
-
Immediate-Early Proteins
-
Interferon Regulatory Factor-1
-
Interferon Regulatory Factor-2
-
Interleukin-6
-
Irf1 protein, mouse
-
Irf2 protein, mouse
-
MYD88 protein, human
-
Myd88 protein, mouse
-
Myd88 protein, rat
-
Myeloid Differentiation Factor 88
-
Phosphoproteins
-
Proteins
-
RNA, Messenger
-
Receptors, Immunologic
-
Repressor Proteins
-
STAT1 Transcription Factor
-
STAT1 protein, human
-
STAT3 Transcription Factor
-
STAT3 protein, human
-
Stat1 protein, mouse
-
Stat3 protein, mouse
-
Trans-Activators
-
Transcription Factors