RRC ID 4797
Author Oshiumi H, Suzuki Y, Matsumoto M, Seya T.
Title Regulator of complement activation (RCA) gene cluster in Xenopus tropicalis.
Journal Immunogenetics
Abstract Genome and expressed sequence tag information of Xenopus tropicalis suggested that short-consensus repeat (SCR)-containing proteins are encoded by three genes that are mapped within a 300-kb downstream of PFKFB2, which is a marker gene for the regulator of complement activation (RCA) loci in human and chicken. Based on this observation, we cloned the three cDNAs of these proteins using 3'- or 5'-RACE technique. Since their primary structures and locations of the proximity to the PFKFB2 locus, we named them amphibian RCA protein (ARC) 1, 2, and 3. Expression in human HEK293 or CHO cells suggested that ARC1 is a soluble protein of Mr approximately 67 kDa, ARC2 is a membrane protein with Mr 44 kDa, and ARC3 a secretary protein with a putative transmembrane region. They were N-glycosylated during maturation. In human and chicken RCA clusters, the order in which genes for soluble, GPI-anchored, and membrane forms of SCR proteins are arranged is from the distant to proximity to the PFKFB2 gene. However, the amphibian ARC1, 2, and 3 resembled one another and did not reflect the same order found in human and chicken RCA genes. This may be due to self-duplication of ARCs to form a family, and it evolved after the amphibia separated from the ancestor of the amniotes, which possessed soluble, GPI-anchored, and membrane forms of SCR protein members. Taken together, frog possesses a RCA locus, but the constitution of the ARC proteins differs from that of the amniotes with a unique self-resemblance.
Volume 61(5)
Pages 371-84
Published 2009-5
DOI 10.1007/s00251-009-0368-9
PMID 19319518
MeSH Animals Cell Line Chickens / genetics Chickens / immunology Complement Activation* Evolution, Molecular* Humans Membrane Glycoproteins / genetics* Membrane Glycoproteins / immunology Multigene Family Xenopus / genetics* Xenopus / immunology* Xenopus Proteins / genetics* Xenopus Proteins / immunology
IF 2.492
Times Cited 8
Human and Animal Cells 293T (RCB2202)
Xenopus tropicalis