Isolation and characterization of the mouse CD8 beta-chain (Ly-3) genes. Absence of an intervening sequence between V- and J-like gene segments.
We have isolated and determined the nucleotide sequence and genomic organization of the genes encoding Ly-3.1 and Ly-3.2. These genes span approximately 14 kb on chromosome 6 and consist of six exons and five introns. The exons correlate roughly with the putative functional domains, namely, a leader exon, a variable and joining region-like exon, a hinge region-like exon, a transmembrane exon, and two intracytoplasmic exons. There is no intervening sequence between V- and J-like gene segments, indicating that rearrangement is not necessary for the expression of the Ly-3 gene. In the 5'-flanking region there is no "TATA" box nor "CAAT" box; however, three "GC" boxes are located upstream of the ATG initiator codon. There are short stretches of sequence homologous to 5'-flanking sequences of the Ly-2 gene. In addition, the sequences CTCTGTGGCA at -748 exhibits homology to the enhancer core sequence of the human Ig H chain and TCR genes. Comparison of the nucleotide sequence corresponding to the extracellular portion between Ly-3.1 and Ly-3.2 revealed a single base difference which results in an amino acid substitution. Therefore it is likely that this amino acid difference is responsible for the previously defined Ly-3 allotypes.
Nakayama
K
K
Department of Immunology, Juntendo University School of Medicine, Tokyo, Japan.
Shinkai
Y I
YI
Okumura
K
K
Nakauchi
H
H
D000595:Amino Acid Sequence; D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics* / Q000302:isolation & purification; D000950:Antigens, Ly / Q000235:genetics* / Q000302:isolation & purification; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000302:isolation & purification; D005091:Exons; D005110:Extracellular Space / Q000032:analysis; D005796:Genes; D052058:Hinge Exons; D007133:Immunoglobulin Joining Region / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D007438:Introns; D051379:Mice; D008806:Mice, Inbred AKR; D008969:Molecular Sequence Data; D014158:Transcription, Genetic
D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly; D007133:Immunoglobulin Joining Region; D007135:Immunoglobulin Variable Region; D004247:DNA