Magnesium and Mg2+ Transport Proteins in Cells
Magnesium and Mg2+ Transport Proteins in Cells
2021 年 21 巻 2 号 p. 55-67
詳細
2021 年 21 巻 2 号 p. 55-67
Magnesium is one of the most important and abundant divalent cations in living cells. Organisms must maintain physiological levels of Mg2+ because this divalent cation is critical for the stabilization of membranes and ribosomes and for the neutralization of nucleic acids. Over 300 enzymes are known to be Mg-dependent. The cellular concentration of Mg2+ is regulated by transmembrane pathways. Prokaryotes carry three classes of Mg2+ transport systems: CorA, MgtE, and MgtA. Some of eukaryotic Mg2+ transport proteins have some similarity to those found in prokaryotes. Mitochondrial RNA splicing protein 2 (MRS2) shares many of properties of the bacterial CorA protein. The Solute Carrier Family 41 Member 1 (SLC41A1) and Cyclin and CBS Domain Divalent Metal Cation Transport Mediator (CNNM) family proteins have a similarity with some regions of the bacterial MgtE and CorC proteins, respectively. Mammalian Mg2+ homeostasis is also regulated by Mg2+ transport proteins including Transient Receptor Potential Cation Channel Subfamily M, Member 6/7 (TRPM6/7), Claudin-16, Magnesium Transporter 1 (MAGT1), and Nonimprinted in Prader-Willi/Angelman Syndrome Region (NIPA) proteins that are not represented in prokaryotic genomes. These eukaryotic Mg2+ transport proteins have no obvious amino acid sequence similarities, indicating that there are many ways to transport Mg2+ across membranes.
