The cloning and nucleotide sequence of human ST2L cDNA

The ST2 gene is a member of the IL-1 receptor family and is hypothesized to be involved in helper T cell function, but its functional ligand and physi ological pole remain unknown. We have cloned the human ST2L cDNA that encod es a distinct type of membrane-bound ST2 protein. The predicted 556-amino-a cid sequence showed 67% identity to the mouse STSL protein. The human ST2 g ene (IL1RL1) contains 13 exons and spans 40 kb in length. Its exon-intron o rganization was elucidated from a registered human genomic sequence derived from chromosome 2q, which contains three other genes belonging to the IL-1 receptor family in an approximately 202-kb genomic region. The tissue dist ribution of ST2 expression was examined by RT-PCR, and the soluble form (ST 2, IL1RL1-a) and STSL (IL1RL1-b) appear to be expressed differentially. We also established stable transfectants of a human glioblastoma cell line, T9 8G, that express human STSL constitutively, and we confirmed cell-surface e xpression of human STSL protein on the transfectants. (C) 2000 Academic Pre ss.