In Saccharomyces cerevisiae, choline enters the cell via a single high-affinity transporter, Hnmlp. hnm1delta cells lacking HNM1 gene are viable. However, they are unable to transport choline suggesting that no additional active choline transporters are present in this organism. A complementation study of a choline auxotrophic mutant, ctrl-ise (hnm1-ise), using a cDNA library from Torpedo marmorata electric lobe identified a membrane protein named Torpedo marmorata choline transporter-like, tCtl1p. tCtllp was proposed to mediate a high-affinity choline transport (O'Regan et al., 1999, Proc. Natl. Acad. Sci.). Homologs of tCtl1p have been identified in other organisms, including yeast (Pns1p, YOR161c) and are postulated to function as choline transporters. Here we provide several lines of evidence indicating that Ctlp proteins are not involved in choline transport. Loss of PNS1 has no effect on choline transport and overexpression of either PNS1 or tCTL1 does not restore choline uptake activity of choline transport-defective mutants. The data presented here call into question the role of proteins of the CTL family in choline transport and suggest that the mechanism by which tCTL1 complements hnm1-ise mutant is independent of its ability to transport choline.
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http://dx.doi.org/10.1023/b:nere.0000013752.43906.e5 | DOI Listing |
Ageing Res Rev
March 2025
Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430. Electronic address:
A key molecule in cellular metabolism, citrate is essential for lipid biosynthesis, energy production, and epigenetic control. The etiology of Alzheimer's disease (AD), a progressive neurodegenerative illness marked by memory loss and cognitive decline, may be linked to dysregulated citrate transport, according to recent research. Citrate transporters, which help citrate flow both inside and outside of cells, are becoming more and more recognized as possible participants in the molecular processes underlying AD.
View Article and Find Full Text PDFMagn Reson Med
March 2025
Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, Illinois, USA.
Purpose: To achieve high-resolution, three-dimensional (3D) quantitative diffusion-weighted MR spectroscopic imaging (DW-MRSI) for molecule-specific microstructural imaging of the brain.
Methods: We introduced and integrated several innovative acquisition and processing strategies for DW-MRSI: (a) a new double-spin-echo sequence combining selective excitation, bipolar diffusion encoding, rapid spatiospectral sampling, interleaved water spectroscopic imaging data, and a special sparsely sampled echo-volume-imaging (EVI)-based navigator, (b) a rank-constrained time-resolved reconstruction from the EVI data to capture spatially varying phases, (c) a model-based phase correction for DW-MRSI data, and (d) a multi-b-value subspace-based method for water/lipids removal and spatiospectral reconstruction using learned metabolite subspaces, and e) a hybrid subspace and parametric model-based parameter estimation strategy. Phantom and in vivo experiments were performed to validate the proposed method and demonstrate its ability to map metabolite-specific diffusion parameters in 3D.
Drug Metab Dispos
January 2025
College of Pharmacy, Department of Pharmacology & Toxicology, The University of Arizona, Tucson, Arizona. Electronic address:
Valsartan (VAL) is commonly prescribed for patients with cardiovascular disease (CVD) to lower blood pressure, reduce heart failure risk, and prevent heart attacks or strokes by blocking the effects of angiotensin II. Many patients with CVD also suffer from metabolic dysfunction-associated steatohepatitis (MASH), which disrupts several xenobiotic transporters, affecting the pharmacokinetics of numerous drugs. Medications used in patients to treat comorbidities associated with MASH may be subject to this altered disposition and potential toxicity.
View Article and Find Full Text PDFJ Hazard Mater
February 2025
Key Laboratory of Human Genetics and Environmental Medicine, School of Public Health, Xuzhou Medical University, 209 Tong-Shan Road, Xuzhou, Jiangsu 221002, China. Electronic address:
2-Ethylhexyl-diphenyl phosphate (EHDPP) is an organophosphate ester (OPE) with roles of flame retardant and plasticizer. It is widely used in various applications, detected in environmental matrices and human body, threatening ecological environment and human health. Some OPEs have been reported to disturb the gut microbiota, the gut microbiota mediates placental function.
View Article and Find Full Text PDFAnn Anat
April 2025
Department of Anatomy, Institute of Health Sciences, Ege University, Izmir, Turkiye; Department of Anatomy School of Medicine, Ege University, Izmir, Turkiye. Electronic address:
Background And Purpose: The dorsal nucleus (Clarke's nucleus, D), lumbar precerebellar nucleus (LPrCb), and sacral precerebellar nucleus (Stilling's sacral nucleus, SPrCb) are precerebellar nuclei of the spinal cord. This study investigates the cytoarchitecture and neurochemical organization of the D, LPrCb, and SPrCb nuclei in the human spinal cord.
Material And Methods: Using Nissl staining and immunohistochemistry for markers including calbindin (Cb), calretinin (Cr), parvalbumin (Pv), choline acetyltransferase (ChAT), glutamic acid decarboxylase (GAD 65/67), and vesicular glutamate transporter 1 (VGLUT1), we analyzed sections from T1-T12, L1-L5, and S1-Co1 segments of a human spinal cord.
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