School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Mol Cell Proteomics. 2023 Nov;22(11):100664. doi: 10.1016/j.mcpro.2023.100664. Epub 2023 Oct 12.
Arginylation is a post-translational modification mediated by the arginyltransferase 1 (ATE1), which transfers the amino acid arginine to a protein or peptide substrate from a tRNA molecule. Initially, arginylation was thought to occur only on N-terminally exposed acidic residues, and its function was thought to be limited to targeting proteins for degradation. However, more recent data have shown that ATE1 can arginylate side chains of internal acidic residues in a protein without necessarily affecting metabolic stability. This greatly expands the potential targets and functions of arginylation, but tools for studying this process have remained limited. Here, we report the first global screen specifically for side-chain arginylation. We generate and validate "pan-arginylation" antibodies, which are designed to detect side-chain arginylation in any amino acid sequence context. We use these antibodies for immunoaffinity enrichment of side-chain arginylated proteins from wildtype and Ate1 knockout cell lysates. In this way, we identify a limited set of proteins that likely undergo ATE1-dependent side-chain arginylation and that are enriched in specific cellular roles, including translation, splicing, and the cytoskeleton.
精氨酸化是一种由精氨酰基转移酶 1（ATE1）介导的翻译后修饰，它将氨基酸精氨酸从 tRNA 分子转移到蛋白质或肽底物上。最初，人们认为精氨酸化仅发生在 N 端暴露的酸性残基上，其功能仅限于将蛋白质靶向降解。然而，最近的数据表明，ATE1 可以精氨酸化蛋白质内部酸性侧链，而不一定影响代谢稳定性。这大大扩展了精氨酸化的潜在靶标和功能，但研究该过程的工具仍然有限。在这里，我们报告了首次专门针对侧链精氨酸化的全局筛选。我们生成并验证了“泛精氨酸化”抗体，这些抗体旨在检测任何氨基酸序列环境中的侧链精氨酸化。我们使用这些抗体从野生型和 Ate1 敲除细胞裂解物中免疫亲和富集侧链精氨酸化蛋白质。通过这种方式，我们鉴定出一组可能发生 ATE1 依赖性侧链精氨酸化的有限蛋白质，这些蛋白质富集在特定的细胞功能中，包括翻译、剪接和细胞骨架。
