Muto A, Watanabe S, Miyajima A, Yokota T, Arai K
Department of Molecular and Developmental Biology, University of Tokyo, Japan.
Biochem Biophys Res Commun. 1995 Mar 8;208(1):368-75. doi: 10.1006/bbrc.1995.1347.
Granulocyte-macrophage colony-stimulating factor receptor (GMR) is composed of two distinct subunits alpha and beta, and the cytoplasmic domains of both subunits are essential to transduce signals. We further analyzed the role of the cytoplasmic domain of each subunit by constructing chimeric subunits, designated alpha/beta and beta/alpha, by exchanging cytoplasmic domains of the alpha and beta subunits of hGMR. Reconstituted high-affinity chimeric hGMRs, hGMR(alpha/beta,beta/alpha) and hGMR(alpha/beta,beta), as well as the wild type hGMR(alpha,beta), transduced signals in Ba/F3 cells. These observations indicate that the original configuration between the extracellular and the cytoplasmic domains of the hGMR(alpha,beta) subunits is not obligatory, and that hGMR(alpha/beta,beta) transduced signals through the cytoplasmic domain of the beta subunit in an oligomeric form, without involvement of the cytoplasmic domain of the alpha subunit.
粒细胞-巨噬细胞集落刺激因子受体（GMR）由两个不同的亚基α和β组成，两个亚基的胞质结构域对于信号转导至关重要。我们通过交换人GMRα和β亚基的胞质结构域构建嵌合亚基，命名为α/β和β/α，进一步分析了每个亚基胞质结构域的作用。重组的高亲和力嵌合人GMR，hGMR(α/β,β/α)和hGMR(α/β,β)，以及野生型hGMR(α,β)，在Ba/F3细胞中传导信号。这些观察结果表明，hGMR(α,β)亚基的细胞外和胞质结构域之间的原始构型并非必需，并且hGMR(α/β,β)以寡聚体形式通过β亚基的胞质结构域传导信号，而不涉及α亚基的胞质结构域。
