Green fluorescence protein,MFS-type transporter SLC18B1,membrane protein spd
キーワード
MEMBRANE PROTEIN
機能・相同性
機能・相同性情報
polyamine:proton antiporter activity / spermidine transport / spermine transport / monoamine:proton antiporter activity / serotonin uptake / transmembrane transporter activity / bioluminescence / secretory granule membrane / generation of precursor metabolites and energy / synaptic vesicle membrane 類似検索 - 分子機能
: / Major facilitator superfamily / Major Facilitator Superfamily / Major facilitator superfamily domain / Major facilitator superfamily (MFS) profile. / MFS transporter superfamily / Green fluorescent protein, GFP / Green fluorescent protein-related / Green fluorescent protein / Green fluorescent protein 類似検索 - ドメイン・相同性
SPERMIDINE / Green fluorescence protein / MFS-type transporter SLC18B1 類似検索 - 構成要素
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01GM145642
米国
引用
ジャーナル: Nat Commun / 年: 2025 タイトル: Structure and mechanism of human vesicular polyamine transporter. 著者: Yi Guo / Ge Yang / Haijiao Liu / Jin Chai / Jie Chen / John Shanklin / Qun Liu / Bin Liu / Min Lu / 要旨: Polyamines play essential roles in gene expression and modulate neuronal transmission in mammals. Vesicular polyamine transporters (VPAT) from the SLC18 family exploit the transmembrane H gradient to ...Polyamines play essential roles in gene expression and modulate neuronal transmission in mammals. Vesicular polyamine transporters (VPAT) from the SLC18 family exploit the transmembrane H gradient to translocate polyamines into secretory vesicles, enabling the quantal release of polyamine neuromodulators and underpinning learning and memory formation. Here, we report the cryo-electron microscopy structures of human VPAT in complex with spermine, spermidine, H, or tetrabenazine, elucidating discrete lumen-facing states of the antiporter and pivotal interactions between VPAT and its substrate or inhibitor. Leveraging structure-inspired mutagenesis studies and protein structure prediction, we deduce an unforeseen mechanism whereby the polyamine and H compete for multiple acidic protein residues both directly and indirectly, and rationalize how the antidopaminergic therapeutic tetrabenazine impedes vesicular transport of polyamines. This study unravels the mechanism of an H-coupled polyamine antiporter, reveals mechanistic diversity between VPAT and other SLC18 antiporters, and raises new prospects for combating human disorders of polyamine homeostasis.