SLC25A38 is required for mitochondrial pyridoxal 5'-phosphate (PLP) accumulation
Izabella A Pena1,2,3, Jeffrey S Shi4,5, Sarah M Chang5,6,7
1The Picower Institute for Learning and Memory, MIT, Cambridge, MA, USA. ipena@cheo.on.ca.
Nature Communications
|January 24, 2025
Summary
Researchers identified SLC25A38 as a key protein regulating mitochondrial pyridoxal 5'-phosphate (the active form of vitamin B6). Its loss impairs cell proliferation and impacts one-carbon metabolism, offering insights into congenital sideroblastic anemia.
Area of Science:
- Biochemistry
- Cell Biology
- Metabolic Regulation
Background:
- Pyridoxal 5 -phosphate (PLP) is essential for numerous metabolic enzymes.
- Mitochondria house a significant portion of PLP-dependent enzymes, yet their regulation remains unclear.
- Understanding mitochondrial PLP homeostasis is crucial for cellular function and disease.
Purpose of the Study:
- To identify molecular regulators of mitochondrial pyridoxal 5 -phosphate levels in mammals.
- To elucidate the function of SLC25A38 in mitochondrial metabolism.
- To investigate the link between SLC25A38 and congenital sideroblastic anemia.
Main Methods:
- Genome-wide CRISPR interference screen in erythroleukemia cells.
- Organellar metabolomics to quantify mitochondrial metabolites.
- Cellular proliferation assays under varying vitamin B6 conditions.
Main Results:
- SLC25A38 was identified as a mitochondrial inner membrane protein regulating mitochondrial PLP.
- Loss of SLC25A38 specifically depletes mitochondrial PLP, impairing cell proliferation.
- Impaired PLP-dependent enzymes, including serine hydroxymethyltransferase-2, were observed, affecting one-carbon and nucleotide synthesis.
Conclusions:
- SLC25A38 plays a critical role in mitochondrial pyridoxal 5 -phosphate accumulation.
- Dysfunction of SLC25A38 contributes to metabolic defects and cellular proliferation issues.
- This study provides a molecular basis for understanding congenital sideroblastic anemia related to vitamin B6 metabolism.
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