拉下实验（Pull-down assay）是一种用于研究蛋白相互作用的技术。通过将一个目标蛋白或蛋白结构域与固定的亲和柱（如琼脂糖珠或亲和树脂）结合，然后在混合物中加入待测样品，从中“拉下”与目标蛋白相互作用的蛋白。随后通过分析拉下的蛋白，可以识别和研究目标蛋白的相互作用伙伴。这一技术有助于揭示蛋白间的直接或间接相互作用，为了解细胞信号传导、蛋白复合物和生物学过程提供重要信息。

Pull-down assay is a technique used to study protein interactions. By binding a target protein or protein domain to an immobilized affinity column (such as agarose beads or affinity resin), and then adding the test sample to the mixture, the proteins that interact with the target protein are "pulled down" from it. By subsequently analyzing the pulled down proteins, the interacting partners of the target protein can be identified and studied. This technology helps reveal direct or indirect interactions between proteins and provides important information for understanding cell signaling, protein complexes and biological processes.