CHARACTERIZATION AND CLONING OF A RECEPTOR FOR BMP-2 AND BMP-4 FROM NIH 3T3 CELLS
CHARACTERIZATION AND CLONING OF A RECEPTOR FOR BMP-2 AND BMP-4 FROM NIH 3T3 CELLS
复制标题
DOI：
10.1128/mcb.14.9.5961
复制
发表时间：
1994-09-01
影响因子：
5.3
通讯作者：
ROSENBAUM, JS
中科院分区：
文献类型：
--
作者：
KOENIG, BB;COOK, JS;ROSENBAUM, JS
骨形态发生蛋白（BMPs）是一组转化生长因子β (tgf - β)相关因子，其受体迄今为止鉴定的唯一受体是秀丽隐杆线虫daf-4基因的产物。小鼠胚胎NIH 3T3成纤维细胞显示高亲和力(125I)-BMP-4结合位点。除非去除带正电荷的n端序列以产生修饰的BMP-2，即I-125-DR-BMP-2，否则不可能与异构体I-125-BMP-2进行结合测定。交叉竞争实验表明BMP-2和BMP-4与相同的结合位点相互作用。亲和交联实验表明，这两种bmp与细胞表面蛋白相互作用，其大小与TGF-P和激活素的I型（57- 62-kDa）和II型（75- 82-kDa）受体组分相对应。利用PCR方法，我们从NIH 3T3细胞中克隆了一个cDNA，该cDNA编码跨膜丝氨酸/苏氨酸激酶家族的一个新成员，与克隆的TGF-P和激活素I型受体最相似。该受体在COS-7细胞中的瞬时表达导致特异性I-125-BMP-4结合增加，并出现一个类似64 kDa的主要亲和标记产物，可以被任何示踪剂标记。由于其结合BMP-2和BMP-4的能力及其受体激酶结构，该受体被命名为BRK-1。虽然BRK-1不需要共转染II型受体来结合COS细胞中的配体，但当BRK-1和BMP II型受体DAF-4被表达、亲和标记，并与任何受体亚基的抗体免疫沉淀时，可以证明BRK-1和DAF-4之间形成复合物。我们得出结论，BRK-1是一种假定的BMP I型受体，能够与BMP的已知II型受体相互作用。
The bone morphogenetic proteins (BMPs) are a group of transforming growth factor beta (TGF-beta)-related factors whose only receptor identified to date is the product of the daf-4 gene from Caenorhabditis elegans. Mouse embryonic NIH 3T3 fibroblasts display high-affinity (125I)-BMP-4 binding sites. Binding assays are not possible with the isoform I-125-BMP-2 unless the positively charged N-terminal sequence is removed to create a modified BMP-2, I-125-DR-BMP-2. Cross-competition experiments reveal that BMP-2 and BMP-4 interact with the same binding sites. Affinity cross-linking assays show that both BMPs interact with cell surface proteins corresponding in size to the type I (57- to 62-kDa) and type II (75- to 82-kDa) receptor components for TGF-P and activin. Using a PCR approach, we have cloned a cDNA from NIH 3T3 cells which encodes a novel member of the transmembrane serine/threonine kinase family most closely resembling the cloned type I receptors for TGF-P and activin. Transient expression of this receptor in COS-7 cells leads to an increase in specific I-125-BMP-4 binding and the appearance of a major affinity-labeled product of similar to 64 kDa that can be labeled by either tracer. This receptor has been named BRK-1 in recognition of its ability to bind BMP-2 and BMP-4 and its receptor kinase structure. Although BRK-1 does not require cotransfection of a type II receptor in order to bind ligand in COS cells, complex: formation between BRK-1 and the BMP type II receptor DAF-4 can be demonstrated when the two receptors are eoexpressed, affinity labeled, and immunoprecipitated with antibodies to either receptor subunit. We conclude that BRK-1 is a putative BMP type I receptor capable of interacting with a known type II receptor for BMPs.