Park Chan-Il, Hirono Ikuo, Hwang Jee Youn, Aoki Takashi
Laboratory of Genome Science, Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Minato, Tokyo, 108-8477, Japan.
Immunogenetics. 2005 Oct;57(9):682-9. doi: 10.1007/s00251-005-0032-y. Epub 2005 Oct 18.
A CD40 homolog cDNA encoding 300 amino acid residues was isolated from a Japanese flounder leukocyte cDNA library. The amino acid sequence identities of Japanese flounder CD40 and previously reported CD40s of cow, human, mouse, and chicken range from 32 to 35%. The positions of cysteine residues, CD40 ligand binding amino acid residues, and four cysteine-rich domains are well conserved in Japanese flounder CD40. The Japanese flounder CD40 gene is composed of nine exons and eight intervening introns spread over 6 kb. The nucleotide sequence of the 5'-flanking region of this gene revealed the presence of several regulatory regions, including a TATA-like box, AP-1-, CEBPB-, IRF-1-, LYF-1-, NF-kappaBp-, SP-1-, and Stat-1-like motifs. In healthy fish, reverse transcriptase-polymerase chain reaction (RT-PCR) detected constitutive expression of CD40 in all tested tissues (leukocytes, kidney, spleen, liver, intestine, brain, gill, and skin). The mRNA of CD40 was predominantly expressed in several tissues that contained lymphocytes (leukocytes, kidney, spleen, intestine, and gill). Expression of the Japanese flounder CD40 molecule was induced in peripheral blood leukocytes from 1 to 6 h following Con A (50 microg/ml)/phorbol myristate acetate (PMA) (0.35 microg/ml) stimulation, with a peak at 1 h after stimulation, and increased at 1, 3, and 6 h after induction by lipopolysaccharide (LPS) (500 microg/ml) compared with the control.
从日本牙鲆白细胞cDNA文库中分离出一个编码300个氨基酸残基的CD40同源cDNA。日本牙鲆CD40与先前报道的牛、人、小鼠和鸡的CD40的氨基酸序列同一性在32%至35%之间。日本牙鲆CD40中半胱氨酸残基、CD40配体结合氨基酸残基以及四个富含半胱氨酸结构域的位置高度保守。日本牙鲆CD40基因由9个外显子和8个间隔内含子组成，分布在6 kb的区域。该基因5'-侧翼区域的核苷酸序列显示存在几个调控区域，包括一个类TATA框、AP-1、CEBPB、IRF-1、LYF-1、NF-κBp、SP-1和Stat-1样基序。在健康鱼类中，逆转录聚合酶链反应（RT-PCR）检测到所有测试组织（白细胞、肾脏、脾脏、肝脏、肠道、大脑、鳃和皮肤）中CD40的组成性表达。CD40的mRNA主要在含有淋巴细胞的几个组织（白细胞、肾脏、脾脏、肠道和鳃）中表达。日本牙鲆CD40分子的表达在Con A（50μg/ml）/佛波酯（PMA）（0.35μg/ml）刺激后1至6小时在外周血白细胞中被诱导，在刺激后1小时达到峰值，并且在脂多糖（LPS）（500μg/ml）诱导后1、3和6小时与对照相比增加。
