Dataset Information

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

ABSTRACT: 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.

SUBMITTER: Kory N

PROVIDER: S-EPMC6300058 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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

Kory Nora N Wyant Gregory A GA Prakash Gyan G Uit de Bos Jelmi J Bottanelli Francesca F Pacold Michael E ME Chan Sze Ham SH Lewis Caroline A CA Wang Tim T Keys Heather R HR Guo Yang Eric YE Sabatini David M DM

Science (New York, N.Y.) 20181101 6416

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 fun ...[more]

PMID: 30442778

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Dataset Information

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

Publications

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

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