Structure and expression of two highly related genes encoding SCM-1/human lymphotactin.
SCM-1/lymphotactin is a chemokine-like molecule produced selectively, if not exclusively, by activated CD8+ T cells. Here we report that there are two highly homologous SCM-1 genes, which we designate as SCM-1alpha and SCM-1beta. Both genes have three exons and two introns. The 1st intron of SCM-1alpha contains a pseudogene of the ribosomal large subunit L7a. In SCM-1beta, a 1.5-kb region including about a quarter of the L7a pseudogene is deleted from the 1st intron. Otherwise, the two genes are highly homologous including the 5' and 3' flanking regions. Both genes were mapped to human chromosome 1q23. The two genes were similarly induced in peripheral blood mononuclear cells by mitogenic stimulation. Primer extension and RNase protection revealed several transcription initiation sites. The biological activities of SCM-1alpha and SCM-1beta, which have two amino acid differences at positions 7 and 8 in the mature proteins, remain to be compared.
Yoshida
T
T
Shionogi Institute for Medical Science, Osaka, Japan.
Imai
T
T
Takagi
S
S
Nishimura
M
M
Ishikawa
I
I
Yaoi
T
T
Yoshie
O
O
D000595:Amino Acid Sequence; D001483:Base Sequence; D002478:Cells, Cultured; D018925:Chemokines / Q000235:genetics*; D019744:Chemokines, C; D002874:Chromosome Mapping; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D003001:Cloning, Molecular; D005091:Exons / Q000235:genetics; D015870:Gene Expression; D005796:Genes; D006367:HeLa Cells; D006801:Humans; D007438:Introns / Q000235:genetics; D008221:Lymphoid Tissue / Q000166:cytology; D008222:Lymphokines / Q000235:genetics*; D008969:Molecular Sequence Data; D011544:Pseudogenes / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D012269:Ribosomal Proteins / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D012795:Sialoglycoproteins / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics
D018925:Chemokines; D019744:Chemokines, C; D008222:Lymphokines; D012333:RNA, Messenger; C057838:RPL7A protein, human; D012269:Ribosomal Proteins; D012795:Sialoglycoproteins; C092390:XCL1 protein, human; C490470:XCL2 protein, human; C018997:lymphotactin