Forkhead box (FOX) family transcription factors play essential roles in development, tissue homeostasis, and disease. Although the biology of several FOX proteins has been studied in depth, it is unclear to what extent these findings apply to even closely related family members, which frequently exert overlapping but non-redundant functions. To help address this question, we have generated a uniform, ready-to-use expression library of all 44 human FOX transcription factors with a convenient peptide tag for parallel screening assays. In addition, we have generated multiple universal forkhead box reporter plasmids, which can be used to monitor the transcriptional activity of most FOX proteins with high fidelity. As a proof-of-principle, we use our plasmid library to identify the DNA repair protein XRCC6/Ku70 as a selective FOX interaction partner and regulator of FOX transcriptional activity. We believe that these tools, which we make available via the Addgene plasmid repository, will considerably expedite the investigation of FOX protein biology.

Forkhead box (FOX) 家族转录因子在发育、组织稳态和疾病中发挥重要作用。尽管已经深入研究了几种 FOX 蛋白的生物学，但尚不清楚这些发现在多大程度上适用于密切相关的家族成员，这些成员经常发挥重叠但非冗余的功能。为了帮助解决这个问题，我们生成了一个统一的、随时可用的表达文库，其中包含所有 44 种人类 FOX 转录因子，并带有一个方便的肽标签，用于平行筛选试验。此外，我们还生成了多个通用叉头盒报告质粒，可用于高保真监测大多数 FOX 蛋白的转录活性。作为原理证明，我们使用我们的质粒文库将 DNA 修复蛋白 XRCC6/Ku70 鉴定为选择性 FOX 相互作用伙伴和 FOX 转录活性的调节剂。我们相信，我们通过 Addgene 质粒库提供的这些工具将大大加快 FOX 蛋白质生物学的研究。