Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China.
State Key Laboratory Cultivation Base for TCM Quality and Efficacy, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China.
Nat Methods. 2022 Jul;19(7):854-864. doi: 10.1038/s41592-022-01523-1. Epub 2022 Jun 27.
Lactylation was initially discovered on human histones. Given its nascence, its occurrence on nonhistone proteins and downstream functional consequences remain elusive. Here we report a cyclic immonium ion of lactyllysine formed during tandem mass spectrometry that enables confident protein lactylation assignment. We validated the sensitivity and specificity of this ion for lactylation through affinity-enriched lactylproteome analysis and large-scale informatic assessment of nonlactylated spectral libraries. With this diagnostic ion-based strategy, we confidently determined new lactylation, unveiling a wide landscape beyond histones from not only the enriched lactylproteome but also existing unenriched human proteome resources. Specifically, by mining the public human Meltome Atlas, we found that lactylation is common on glycolytic enzymes and conserved on ALDOA. We also discovered prevalent lactylation on DHRS7 in the draft of the human tissue proteome. We partially demonstrated the functional importance of lactylation: site-specific engineering of lactylation into ALDOA caused enzyme inhibition, suggesting a lactylation-dependent feedback loop in glycolysis.
乳酰化最初在人类组蛋白上被发现。由于其处于初期阶段，它在非组蛋白上的存在及其下游功能后果仍然难以捉摸。在这里，我们报告了在串联质谱过程中形成的乳酰赖氨酸的环状亚铵离子，该离子可用于可靠的蛋白质乳酰化分配。我们通过亲和富集乳酰蛋白组分析和对非乳酰化光谱文库的大规模信息评估，验证了该离子对乳酰化的灵敏度和特异性。通过这种基于诊断离子的策略，我们可以自信地确定新的乳酰化，揭示了不仅在富集的乳酰蛋白组中，而且在现有的未富集的人类蛋白质组资源中广泛存在的乳酰化。具体来说，通过挖掘公共人类 Meltome 图谱，我们发现乳酰化在糖酵解酶上很常见，并且在 ALDOA 上保守。我们还在人类组织蛋白质组草案中发现了 DHRS7 上普遍存在的乳酰化。我们部分证明了乳酰化的功能重要性：将乳酰化定点工程引入 ALDOA 会导致酶抑制，这表明糖酵解中存在乳酰化依赖的反馈回路。
