Publications

• SFXN1 is a mitochondrial serine transporter required for one-carbon metabolism.

  Kory N., Wyant G.A., Prakash G., Uit de Bos J., Bottanelli F., Pacold M.E., Chan S.H., Lewis C.A., Wang T., Keys H.R., Guo Y.E., Sabatini D.M.

  One-carbon metabolism generates the one-carbon units required to synthesize many critical metabolites, including nucleotides. The pathway has cytosolic and mitochondrial branches, and a key step is the entry, through an unknown mechanism, of serine into mitochondria, where it is converted into gly ... >> More

  One-carbon metabolism generates the one-carbon units required to synthesize many critical metabolites, including nucleotides. The pathway has cytosolic and mitochondrial branches, and a key step is the entry, through an unknown mechanism, of serine into mitochondria, where it is converted into glycine and formate. In a CRISPR-based genetic screen in human cells for genes of the mitochondrial pathway, we found sideroflexin 1 (SFXN1), a multipass inner mitochondrial membrane protein of unclear function. Like cells missing mitochondrial components of one-carbon metabolism, those null for SFXN1 are defective in glycine and purine synthesis. Cells lacking SFXN1 and one of its four homologs, SFXN3, have more severe defects, including being auxotrophic for glycine. Purified SFXN1 transports serine in vitro. Thus, SFXN1 functions as a mitochondrial serine transporter in one-carbon metabolism. << Less

  Science 362:0-0(2018) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Cloning and characterization of a human brain Na+-independent transporter for small neutral amino acids that transports D-serine with high affinity.

  Nakauchi J., Matsuo H., Kim D.K., Goto A., Chairoungdua A., Cha S.H., Inatomi J., Shiokawa Y., Yamaguchi K., Saito I., Endou H., Kanai Y.

  We isolated a cDNA for the human homologue of system asc transporter Asc-1 from human brain. The encoded protein designated as hAsc-1 (human Asc-1) exhibited 91 % sequence identity to mouse Asc-1. Consistent with mouse Asc-1, hAsc-1 required 4F2 heavy chain for its functional expression in Xenopus ... >> More

  We isolated a cDNA for the human homologue of system asc transporter Asc-1 from human brain. The encoded protein designated as hAsc-1 (human Asc-1) exhibited 91 % sequence identity to mouse Asc-1. Consistent with mouse Asc-1, hAsc-1 required 4F2 heavy chain for its functional expression in Xenopus oocytes. hAsc-1 exhibited the properties of amino acid transport system asc which transports small neutral amino acids in a Na(+)-independent manner. hAsc-1 transported D-serine at high affinity with a K(m) value of 22.8 microM. In brain, 2.0 kb mRNA was highly expressed. hAsc-1 gene was mapped to human chromosome 19, region q12-q13.1. Because of the high-affinity transport with the K(m) value close to the physiological concentration of D-serine, together with the high levels of expression in brain, hAsc-1 is proposed to play significant roles in the D-serine mobilization in brain. << Less

  Neurosci. Lett. 287:231-235(2000) [PubMed] [EuropePMC]

  This publication is cited by 6 other entries.