The chicken RelB transcription factor has transactivation sequences and a tissue-specific expression pattern that are distinct from mammalian RelB.
Rel/NF-kappaB proteins are eukaryotic transcription factors that control the expression of genes involved in a large variety of cellular processes. Rel proteins share a highly conserved DNA-binding/dimerization domain called the Rel Homology (RH) domain. We have constructed and characterized a composite cDNA encoding most of the chicken RelB transcription factor. The predicted chicken RelB protein has a high degree of sequence similarity to other vertebrate RelB proteins within the RH domain, but is much less conserved outside this domain. Chicken RelB does not bind DNA as a homodimer, but forms DNA-binding heterodimers with NF-kappaB p50 or p52. Overexpressed chicken RelB localizes to the nucleus in chicken embryo fibroblasts, and the nonconserved C-terminal sequences of chicken RelB contain a transactivation domain that functions in chicken and mouse fibroblasts. Thus, chicken RelB has functional properties similar to other vertebrate RelB proteins. However, Western blotting of diverse chicken tissues indicates that chicken RelB is more widely expressed than mammalian RelB.
Piffat
K A
KA
Department of Biology, Boston University, Boston, Massachusetts 02215, USA.
Hrdlicková
R
R
Nehyba
J
J
Ikeda
T
T
Liss
A
A
Huang
S
S
Sif
S
S
Gilmore
T D
TD
Bose
H R
HR
D021581:Active Transport, Cell Nucleus; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D002478:Cells, Cultured; D002645:Chickens; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004247:DNA / Q000235:genetics / Q000378:metabolism; D005347:Fibroblasts; D020869:Gene Expression Profiling; D008322:Mammals; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009928:Organ Specificity; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020218:Response Elements / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D051841:Transcription Factor RelB; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation
D011518:Proto-Oncogene Proteins; D014157:Transcription Factors; D051841:Transcription Factor RelB; D004247:DNA