The transcription factor, Bright, is not expressed in all human B lymphocyte subpopulations.
Bright is an ARID family transcription factor that increases immunoglobulin heavy chain transcription. In the mouse, Bright expression is tightly regulated and B cell-restricted and the Bright protein associates with Bruton's tyrosine kinase (Btk), the defective enzyme in X-linked immunodeficiency. Human X-linked agammaglobulinemia results from defects in Btk and leads to early blocks in B lymphocyte development. Because so little is known about human Bright, we sought to determine where human Bright is expressed in normal B cell differentiation and whether it also forms complexes with Btk. Although human and mouse Bright exhibited similar expression patterns in normal B cells, many human transformed B cell lines did not express Bright protein. However, the human protein bound prototypic Bright DNA-binding motifs and, like mouse Bright, was capable of associating with Btk. These data suggest potentially important similarities exist in Bright expression and activity in human and mouse B lymphocytes.
Nixon
Jamee C
JC
Department of Microbiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
Rajaiya
Jaya B
JB
Ayers
Neil
N
Evetts
Seth
S
Webb
Carol F
CF
D000077329:Agammaglobulinaemia Tyrosine Kinase; D016175:B-Lymphocyte Subsets / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D002461:Cell Line, Transformed; D016384:Consensus Sequence; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D018858:Germinal Center / Q000378:metabolism; D006801:Humans; D009857:Oncogenes / Q000235:genetics; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D013234:Stem Cells / Q000378:metabolism; D014018:Tissue Distribution; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
C490798:ARID3A protein, human; D004268:DNA-Binding Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D004247:DNA; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625949:BTK protein, human; C000625951:Btk protein, mouse