Retrovirally mediated complementation of the glyB phenotype. Cloning of a human gene encoding the carrier for entry of folates into mitochondria.
The transduction of a human placental cDNA retroviral library into glyB cells, a Chinese hamster ovary K1 subline that is deficient in the transport of folates into mitochondria, resulted in the complementation of glycine auxotrophy of these cells. A 2.6-kilobase pair cDNA insert flanked by retroviral sequences had integrated into genomic DNA in rescued cells. An open reading frame in this cDNA encoded a 35-kDa protein homologous to several inner mitochondrial wall transporters for intermediate metabolites. The subcloned cDNA complemented the glycine auxotrophy of glyB cells and reinstated folate accumulation in the mitochondria of transfected cells. The human origin, chromosomal location, and intron-exon organization of the isolated mitochondrial folate transporter gene were deduced from the expressed sequence tag database and human genome project data.
Titus
S A
SA
Department of Pharmacology and Toxicology and the Massey Cancer Center, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia 23298, USA.
Moran
R G
RG
D000595:Amino Acid Sequence; D000818:Animals; D001693:Biological Transport, Active / Q000235:genetics; D016466:CHO Cells; D002352:Carrier Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D006224:Cricetinae; D020224:Expressed Sequence Tags; D005492:Folic Acid / Q000378:metabolism*; D015723:Gene Library; D005816:Genetic Complementation Test; D005998:Glycine / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics*; D026901:Membrane Transport Proteins; D008928:Mitochondria / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010641:Phenotype; D010920:Placenta; D012190:Retroviridae
D002352:Carrier Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C417506:SLC25A32 protein, human; D005492:Folic Acid; D005998:Glycine