| Autor: |
Kobayashi, Takaaki A., Shimada, Hiroto, Sano, Fumiya K., Itoh, Yuzuru, Enoki, Sawako, Okada, Yasushi, Kusakizako, Tsukasa, Nureki, Osamu |
| Předmět: |
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| Zdroj: |
Nature Communications; 7/2/2024, Vol. 15 Issue 1, p1-12, 12p |
| Abstrakt: |
Vitamin C plays important roles as a cofactor in many enzymatic reactions and as an antioxidant against oxidative stress. As some mammals including humans cannot synthesize vitamin C de novo from glucose, its uptake from dietary sources is essential, and is mediated by the sodium-dependent vitamin C transporter 1 (SVCT1). Despite its physiological significance in maintaining vitamin C homeostasis, the structural basis of the substrate transport mechanism remained unclear. Here, we report the cryo-EM structures of human SVCT1 in different states at 2.5–3.5 Å resolutions. The binding manner of vitamin C together with two sodium ions reveals the counter ion-dependent substrate recognition mechanism. Furthermore, comparisons of the inward-open and occluded structures support a transport mechanism combining elevator and distinct rotational motions. Our results demonstrate the molecular mechanism of vitamin C transport with its underlying conformational cycle, potentially leading to future industrial and medical applications. Vitamin C is an essential nutrient for our daily life, but how it is transported into our bodies remained unclear. Here, authors revealed multiple structures of human vitamin C transporter, providing insights into its molecular mechanisms. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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