title: Novel member of the CD209 (DC-SIGN) gene family in primates.
abstract: Two CD209 family genes identified in humans, CD209 (DC-SIGN) and CD209L (DC-SIGNR/L-SIGN), encode C-type lectins that serve as adhesion receptors for ICAM-2 and ICAM-3 and participate in the transmission of human and simian immunodeficiency viruses (HIV and SIV, respectively) to target cells in vitro. Here we characterize the CD209 gene family in nonhuman primates and show that recent evolutionary alterations have occurred in this family across primate species. All of the primate species tested, specifically, Old World monkeys (OWM) and apes, have orthologues of human CD209. In contrast, CD209L is missing in OWM but present in apes. A third family member, that we have named CD209L2, was cloned from rhesus monkey cDNA and subsequently identified in OWM and apes but not in humans. Rhesus CD209L2 mRNA was prominently expressed in the liver and axillary lymph nodes, although preliminary data suggest that levels of expression may vary among individuals. Despite a high level of sequence similarity to both human and rhesus CD209, rhesus CD209L2 was substantially less effective at binding ICAM-3 and poorly transmitted HIV type 1 and SIV to target cells relative to CD209. Our data suggest that the CD209 gene family has undergone recent evolutionary processes involving duplications and deletions, the latter of which may be tolerated because of potentially redundant functional activities of the molecules encoded by these genes.
authors.affiliation: Science Application International Corporation at Frederick, Laboratory of Genomic Diversity, National Cancer Institute at Frederick, Maryland 21702, USA.
authors.forename: Arman A
authors.initials: AA
authors.lastname: Bashirova
authors.forename: Li
authors.initials: L
authors.lastname: Wu
authors.forename: Jie
authors.initials: J
authors.lastname: Cheng
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Martin
authors.forename: Maureen P
authors.initials: MP
authors.lastname: Martin
authors.forename: Raoul E
authors.initials: RE
authors.lastname: Benveniste
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Lifson
authors.forename: Vineet N
authors.initials: VN
authors.lastname: KewalRamani
authors.forename: Austin
authors.initials: A
authors.lastname: Hughes
authors.forename: Mary
authors.initials: M
authors.lastname: Carrington
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015139:Blotting, Southern; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D020869:Gene Expression Profiling; D037181:Lectins, C-Type / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D011323:Primates / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D016097:Simian Acquired Immunodeficiency Syndrome / Q000635:transmission; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D015815:Cell Adhesion Molecules; D037181:Lectins, C-Type; D011956:Receptors, Cell Surface; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin