Walter P, Blobel G
Cell. 1983 Sep;34(2):525-33. doi: 10.1016/0092-8674(83)90385-9.
Signal recognition particle (SRP) is a ribonucleoprotein consisting of six distinct polypeptides and one molecule of small cytoplasmic 7SL-RNA. The particle was previously shown to function in protein translocation across, and protein integration into, the endoplasmic reticulum membrane. A rapid procedure was developed to disassemble SRP into native protein and RNA components. The method utilizes unfolding of SRP with EDTA and dissociation on polycationic matrixes. SRP proteins prepared this way sediment below 7S and are inactive in activity assays. When recombined with 7SL-RNA in the presence of magnesium, the proteins are shown to reassociate stoichiometrically with 7SL-RNA to form fully active 11S SRP.
信号识别颗粒（SRP）是一种核糖核蛋白，由六种不同的多肽和一分子小细胞质7SL-RNA组成。先前已证明该颗粒在蛋白质跨内质网膜转运以及蛋白质整合到内质网膜中发挥作用。已开发出一种快速程序，可将SRP分解为天然蛋白质和RNA成分。该方法利用EDTA使SRP展开并在聚阳离子基质上解离。以这种方式制备的SRP蛋白在7S以下沉降，并且在活性测定中无活性。当在镁存在下与7SL-RNA重组时，这些蛋白质显示出与7SL-RNA化学计量地重新结合，形成完全活性的11S SRP。
