Characterization of paired Ig-like receptors in rats.
To explore the phylogenetic history of the murine paired Ig-like receptors of activating (PIR-A) and inhibitory (PIR-B) types, we isolated PIR homologues from a rat splenocyte cDNA library. The rat (ra) PIR-A and raPIR-B cDNA sequences predict transmembrane proteins with six highly conserved extracellular Ig-like domains and distinctive membrane proximal, transmembrane, and cytoplasmic regions. The raPIR-B cytoplasmic region contains prototypic inhibitory motifs, whereas raPIR-A features a charged transmembrane region and a short cytoplasmic tail. Southern blot analysis predicts the presence of multiple Pira genes and a single Pirb gene in the rat genome. Although raPIR-A and raPIR-B are coordinately expressed by myeloid cells, analysis of mRNA detected unpaired expression of raPIR-A by B cells and raPIR-B by NK cells. Collectively, these findings indicate that the structural hallmarks of the Pir gene family are conserved in rats and mice, yet suggest divergence of PIR regulatory elements during rodent speciation.
Dennis
G
G
Division of Developmental and Clinical Immunology, Department of Microbiology, University of Alabama, Birmingham 35294, USA.
Stephan
R P
RP
Kubagawa
H
H
Cooper
M D
MD
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D018076:DNA, Complementary / Q000302:isolation & purification; D004285:Dogs; D005260:Female; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010802:Phylogeny; D011817:Rabbits; D051381:Rats; D011917:Rats, Inbred Lew; D017207:Rats, Sprague-Dawley; D011971:Receptors, Immunologic / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D012689:Sequence Homology, Nucleic Acid
D018076:DNA, Complementary; C105948:Pira1 protein, mouse; C105949:Pirb protein, mouse; C491380:Pirb protein, rat; D011971:Receptors, Immunologic