National Natural Science Foundation of China (NSFC)
32130057
中国
National Natural Science Foundation of China (NSFC)
31922037
中国
National Natural Science Foundation of China (NSFC)
81921005
中国
National Natural Science Foundation of China (NSFC)
32171219
中国
National Natural Science Foundation of China (NSFC)
82001681
中国
引用
ジャーナル: Nature / 年: 2022 タイトル: Recognition of cyclic dinucleotides and folates by human SLC19A1. 著者: Qixiang Zhang / Xuyuan Zhang / Yalan Zhu / Panpan Sun / Liwei Zhang / Junxiao Ma / Yong Zhang / Lingan Zeng / Xiaohua Nie / Yina Gao / Zhaolong Li / Songqing Liu / Jizhong Lou / Ang Gao / Liguo Zhang / Pu Gao / 要旨: Cyclic dinucleotides (CDNs) are ubiquitous signalling molecules in all domains of life. Mammalian cells produce one CDN, 2'3'-cGAMP, through cyclic GMP-AMP synthase after detecting cytosolic DNA ...Cyclic dinucleotides (CDNs) are ubiquitous signalling molecules in all domains of life. Mammalian cells produce one CDN, 2'3'-cGAMP, through cyclic GMP-AMP synthase after detecting cytosolic DNA signals. 2'3'-cGAMP, as well as bacterial and synthetic CDN analogues, can act as second messengers to activate stimulator of interferon genes (STING) and elicit broad downstream responses. Extracellular CDNs must traverse the cell membrane to activate STING, a process that is dependent on the solute carrier SLC19A1. Moreover, SLC19A1 represents the major transporter for folate nutrients and antifolate therapeutics, thereby placing SLC19A1 as a key factor in multiple physiological and pathological processes. How SLC19A1 recognizes and transports CDNs, folate and antifolate is unclear. Here we report cryo-electron microscopy structures of human SLC19A1 (hSLC19A1) in a substrate-free state and in complexes with multiple CDNs from different sources, a predominant natural folate and a new-generation antifolate drug. The structural and mutagenesis results demonstrate that hSLC19A1 uses unique yet divergent mechanisms to recognize CDN- and folate-type substrates. Two CDN molecules bind within the hSLC19A1 cavity as a compact dual-molecule unit, whereas folate and antifolate bind as a monomer and occupy a distinct pocket of the cavity. Moreover, the structures enable accurate mapping and potential mechanistic interpretation of hSLC19A1 with loss-of-activity and disease-related mutations. Our research provides a framework for understanding the mechanism of SLC19-family transporters and is a foundation for the development of potential therapeutics.