TY - JOUR
T1 - Comprehensive analysis and characterization of the TCR α chain sequences in the common marmoset
AU - Fujii, Yoshiki
AU - Matsutani, Takaji
AU - Kitaura, Kazutaka
AU - Suzuki, Satsuki
AU - Itoh, Tsunetoshi
AU - Takasaki, Tomohiko
AU - Suzuki, Ryuji
AU - Kurane, Ichiro
N1 - Funding Information:
Acknowledgments This work was in part supported by Grants-in-Aids for Research on Emerging and Re-emerging Infectious Diseases by the Ministry of Health, Labor and Welfare, Japan (grant H20-shinkou-ippan-015) and Research on Publicly Essential Drug and Medical Devices from the Japan Health Sciences Foundation (grants KH53333 and KHC3332).
PY - 2010/6
Y1 - 2010/6
N2 - The common marmoset (Callithrix jacchus) is useful as a nonhuman primate model of human diseases. Although the marmoset model has great potential for studying autoimmune diseases and immune responses against pathogens, little information is available regarding the genes involved in adaptive immunity. Here, we identified one TCR α constant (TRAC), 46 TRAJ (joining), and 35 TRAV (variable) segments from marmoset cDNA. Marmoset TRAC, TRAJ, and TRAV shared 80%, 68-100%, and 79-98% identity with their human counterparts at the amino acid level, respectively. The amino acid sequences were less conserved in TRAC than in TCRβ chain constant (TRBC). Comparative analysis of TRAV between marmosets and humans showed that the rates of synonymous substitutions per site (d S ) were not significantly different between the framework regions (FRs) and complementarity determining regions (CDRs), whereas the rates of nonsynonymous substitutions per site (d N ) were significantly lower in the FRs than in CDRs. Interestingly, the d N values of the CDRs were greater for TRBV than TRAV. These results suggested that after the divergence of Catarrhini from Platyrrhini, amino acid substitutions were decreased in the FRs by purifying selection and occurred more frequently in CDRβ than in CDRα by positive selection, probably depending on structural and functional constraints. This study provides not only useful information facilitating the investigation of adaptive immunity using the marmoset model but also new insight into the molecular evolution of the TCR heterodimer in primate species.
AB - The common marmoset (Callithrix jacchus) is useful as a nonhuman primate model of human diseases. Although the marmoset model has great potential for studying autoimmune diseases and immune responses against pathogens, little information is available regarding the genes involved in adaptive immunity. Here, we identified one TCR α constant (TRAC), 46 TRAJ (joining), and 35 TRAV (variable) segments from marmoset cDNA. Marmoset TRAC, TRAJ, and TRAV shared 80%, 68-100%, and 79-98% identity with their human counterparts at the amino acid level, respectively. The amino acid sequences were less conserved in TRAC than in TCRβ chain constant (TRBC). Comparative analysis of TRAV between marmosets and humans showed that the rates of synonymous substitutions per site (d S ) were not significantly different between the framework regions (FRs) and complementarity determining regions (CDRs), whereas the rates of nonsynonymous substitutions per site (d N ) were significantly lower in the FRs than in CDRs. Interestingly, the d N values of the CDRs were greater for TRBV than TRAV. These results suggested that after the divergence of Catarrhini from Platyrrhini, amino acid substitutions were decreased in the FRs by purifying selection and occurred more frequently in CDRβ than in CDRα by positive selection, probably depending on structural and functional constraints. This study provides not only useful information facilitating the investigation of adaptive immunity using the marmoset model but also new insight into the molecular evolution of the TCR heterodimer in primate species.
KW - Common marmoset
KW - Comparative immunology
KW - Evolution
KW - T cell receptors
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U2 - 10.1007/s00251-010-0445-0
DO - 10.1007/s00251-010-0445-0
M3 - Article
C2 - 20405119
AN - SCOPUS:77953161071
VL - 62
SP - 383
EP - 395
JO - Immunogenetics
JF - Immunogenetics
SN - 0093-7711
IS - 6
ER -