Miller M D, Hata S, De Waal Malefyt R, Krangel M S
Division of Tumor Virology, Dana-Farber Cancer Institute, Boston, MA 02115.
J Immunol. 1989 Nov 1;143(9):2907-16.
We have identified two cDNA clones, I-309 and G-26, which define genes expressed abundantly in activated human PBMC, but at low or undetectable levels in resting PBMC. Based upon nucleotide sequence analysis, both clones are predicted to encode small, structurally related polypeptides, each containing a hydrophobic leader sequence characteristic of secreted proteins and a motif of four conserved cysteine residues. Further, I-309 and G-26 are structurally related to a growing family of genes that apparently encode small polypeptides whose secretion is induced upon cell activation. I-309 represents a previously undescribed human gene. We have generated an anti-peptide antiserum to the I-309 gene product which recognizes proteins in culture supernatants of an activated T cell clone and of COS cells transfected with the I-309 cDNA, supporting the idea that I-309 encodes a secreted protein. Because I-309 encodes a small protein secreted by activated T cells that displays structural features similar to other cytokines, we believe that it defines a novel cytokine with as yet unknown function.
我们已鉴定出两个cDNA克隆，即I - 309和G - 26，它们所定义的基因在活化的人外周血单核细胞（PBMC）中大量表达，但在静息PBMC中表达水平很低或无法检测到。基于核苷酸序列分析，预计这两个克隆都编码小的、结构相关的多肽，每个多肽都含有分泌蛋白特有的疏水前导序列和四个保守半胱氨酸残基的基序。此外，I - 309和G - 26在结构上与一个不断扩大的基因家族相关，这些基因显然编码小多肽，其分泌在细胞活化时被诱导。I - 309代表一个以前未描述的人类基因。我们已针对I - 309基因产物产生了一种抗肽抗血清，该抗血清可识别活化T细胞克隆和用I - 309 cDNA转染的COS细胞培养上清液中的蛋白质，这支持了I - 309编码一种分泌蛋白的观点。由于I - 309编码一种由活化T细胞分泌的小蛋白，该蛋白具有与其他细胞因子相似的结构特征，我们认为它定义了一种功能未知的新型细胞因子。
