title: PAT4 is abundantly expressed in excitatory and inhibitory neurons as well as epithelial cells.
abstract: PAT4, the fourth member of the SLC36/proton dependent amino acid transporter (PAT) family, is a high-affinity, low capacity electroneutral transporter of neutral amino acids like proline and tryptophan. It has also been associated with the function of mTORC1, a complex in the mammalian target of rapamycin (mTOR) pathway. We performed in situ hybridization and immunohistological analysis to determine the expression profile of PAT4, as well as an RT-PCR study on tissue from mice exposed to leucine. We performed a phylogenetic analysis to determine the evolutionary origin of PAT4. The in situ hybridization and the immunohistochemistry on mouse brain sections and hypothalamic cells showed abundant PAT4 expression in the mouse brain intracellularly in both inhibitory and excitatory neurons, partially co-localizing with lysosomal markers and epithelial cells lining the ventricles. Its location in epithelial cells around the ventricles indicates a transport of substrates across the blood brain barrier. Phylogenetic analysis showed that PAT4 belongs to an evolutionary old family most likely predating animals, and PAT4 is the oldest member of that family.
authors: Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, SE 75124, Sweden. Electronic address: Sahar.Roshanbin@neuro.uu.se.
authors: Sahar
authors: S
authors: Roshanbin
authors: Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, SE 75124, Sweden. Electronic address: Sofie.Hellsten@neuro.uu.se.
authors: Sofie V
authors: SV
authors: Hellsten
authors: Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, SE 75124, Sweden. Electronic address: atieh.tafreshiha@gmail.com.
authors: Atieh
authors: A
authors: Tafreshiha
authors: Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, SE 75124, Sweden. Electronic address: zhuyinan0108@gmail.com.
authors: Yinan
authors: Y
authors: Zhu
authors: Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, SE 75124, Sweden. Electronic address: Amanda.raine@medsci.uu.se.
authors: Amanda
authors: A
authors: Raine
authors: Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, SE 75124, Sweden. Electronic address: Robert.Fredriksson@neuro.uu.se.
authors: Robert
authors: R
authors: Fredriksson
mesh_terms: D026905:Amino Acid Transport Systems / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000098:blood supply / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002831:Choroid Plexus / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism*; D015870:Gene Expression; D006624:Hippocampus / Q000098:blood supply / Q000378:metabolism; D007031:Hypothalamus / Q000098:blood supply / Q000378:metabolism; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007930:Leucine / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000378:metabolism*; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D026905:Amino Acid Transport Systems; C583919:PAT4 protein, mouse; D012333:RNA, Messenger; D007930:Leucine
keywords: Amino acid transporter; Brain; Immunoflourescence; Immunohistochemistry; In situ hybridization; Lysosomal transporter; Mouse; PAT4; SLC36; SLC36A4