释义：

The λ repressor two-hybrid system is a protein-protein interaction technique mainly used to study the direct interaction between two proteins. This method employs fusion technology to link the protein of interest (bait) with the λ repressor protein, which contains a DNA-binding domain and a dimerization domain. The bait protein specifically binds to the λ operator sequence through the DNA-binding domain of the λ repressor, which is located upstream of the reporter gene promoter.
The corresponding target protein (prey) is fused to the N-terminal of the RNA polymerase α subunit. When the bait and prey proteins meet and interact within the cell, their binding promotes the stable binding of RNA polymerase to the promoter, thus initiating the transcription of the reporter gene (such as HIS3). The protein interaction is detected by measuring the activity of the reporter gene to determine the presence and strength of the interaction.
However, since both the λ repressor protein and the N-terminal of the RNA polymerase α subunit have a tendency to dimerize, this may affect the interpretation of the experimental results, especially when analyzing proteins that have an inherent tendency to aggregate. Therefore, this system is more suitable for studying proteins whose interactions depend on aggregation with other proteins.

λ抑制子双杂交法是一种蛋白质-蛋白质互作技术，主要用于研究两种蛋白质之间的直接相互作用。这种方法通过融合技术将感兴趣的蛋白质 (诱饵) 与λ抑制蛋白结合，λ抑制蛋白包含一个DNA结合域和一个二聚化域。诱饵蛋白通过λ抑制蛋白的DNA结合域能够特异性地绑定到λ操纵子序列上，该序列位于报告基因的启动子上游。
相应的靶蛋白 (猎物) 则与RNA聚合酶的α亚基N端融合。当诱饵与猎物蛋白在细胞内相遇并相互作用时，它们的结合促使RNA聚合酶稳定地绑定到启动子上，从而启动报告基因 (如HIS3) 的转录，实验通过测量报告基因的活性来检测蛋白质互作的存在和强度。
然而，由于λ抑制蛋白和RNA聚合酶α亚基N端都具有二聚化倾向，这可能会影响实验结果的解释，尤其是在分析那些自身具有聚合倾向的蛋白质时。因此，这种系统更适用于研究那些其互作依赖于与其他蛋白质聚合的蛋白质。