ICAM-3, a ligand for DC-SIGN, was duplicated from ICAM-1 in mammalian evolution, but was lost in the rodent genome.
ICAM-3 is a DC-SIGN ligand that is constitutively expressed on resting leukocytes, and is thus an important molecule for the first immune response. But, ICAM-3 has not been isolated form rodents. Thus, we compare the ICAM gene clusters in human, dog, mouse, and rat. ICAM-1, -4, -5 and -3 are located close to one another on the same chromosome and show genomic synteny in human and dog. Almost the same ICAM gene clusters were found in rodent genome, but only the ICAM-3 was not present. A phylogenetic tree plotting the cDNAs of human, dog, mouse, rat, and bovine suggested that ICAM-3 was made from a duplication of ICAM-1. Thus, ICAM-3 arose from ICAM-1 in the mammalian evolution, but was lost in the rodent's genome. Our study suggests the different immune response in the rodents in comparison with other mammals.
Sugino
Hidehiko
H
Laboratories for Integrated Biology, Graduate School of Frontier Biosciences, Osaka University, Japan. sugino@fbs.osaka-u.ac.jp
D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D017931:DNA Primers; D019143:Evolution, Molecular; D016678:Genome; D006801:Humans; D037181:Lectins, C-Type / Q000378:metabolism*; D008024:Ligands; D016133:Polymerase Chain Reaction; D011956:Receptors, Cell Surface / Q000378:metabolism*; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
D015703:Antigens, CD; D015815:Cell Adhesion Molecules; D017931:DNA Primers; D037181:Lectins, C-Type; D008024:Ligands; D011956:Receptors, Cell Surface; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin; C483616:ICAM3 protein, human