I. Hwang et Pd. Gottlieb, THE BOP GENE ADJACENT TO THE MOUSE CD8B GENE ENCODES DISTINCT ZINC-FINGER PROTEINS EXPRESSED IN CTLS AND IN MUSCLE, The Journal of immunology, 158(3), 1997, pp. 1165-1174
The Bop gene (for CD8b opposite) is located immediately upstream of th
e mouse CD86 gene. Expression of Bop gene transcripts was previously o
bserved in several long term CTL lines and in thymus. The present stud
ies demonstrate that expression of the Bop gene in lymphocytes appears
to be confined to CD8-positive cells, and that Bop gene expression is
inducible by Con A. They further show that a single Bop gene encodes
protein products with distinct amino-terminal sequences that are expre
ssed in CTLs (t-BOP) and in cardiac and skeletal muscle (skm-BOP), as
well as what appears to be a noncoding cDNA (t-ncb) expressed only in
CTLs. The t-BOP and t-ncb cDNAs in CTLs result from alternative splici
ng of a single primary transcript, whereas the Bop transcripts express
ed in CTLs and in muscle appear to be transcribed from different promo
ters. The BOP proteins expressed in CTLs and muscle contain zinc finge
r-like motifs with homology to those of the ETO/MTG8 proto-oncogene an
d several other proteins of interest. Western blot analysis with a ham
ster anti-BOP mAb have detected the BOP protein in muscle cells and in
COS 7 cells transfected with Bop cDNA constructs.