The tea plant CsLHT1 and CsLHT6 transporters take up amino acids, as a nitrogen source, from the soil of organic tea plantations

AbstractOrganic tea is more popular than conventional tea that originates from fertilized plants. Amino acids inorganic soils constitute a substantial pool nitrogen (N) available for plants. However, the amino-acid contents in soils of tea plantations and how tea plants take up these amino acids remain largely unknown. In this study, we show that the amino-acid content in the soil of an organic tea plantation is significantly higher than that of a conventional tea plantation. Glutamate, alanine, valine, and leucine were the most abundant amino acids in the soil of this tea plantation. When 15N-glutamate was fed to tea plants, it was efficiently absorbed and significantly increased the contents of other amino acids in the roots. We cloned seven CsLHT genes encoding amino-acid transporters and found that the expression of CsLHT1, CsLHT2, and CsLHT6 in the roots significantly increased upon glutamate feeding. Moreover, the expression of CsLHT1 or CsLHT6 in a yeast amino-acid uptake-defective mutant, 22∆10α, enabled growth on media with amino acids constituting the sole N source. Amino-acid uptake assays indicated that CsLHT1 and CsLHT6 are H+-dependent high- and low-affinity amino-acid transporters, respectively. We further demonstrated that CsLHT1 and CsLHT6 are highly expressed in the roots and are localized to the plasma membrane. Moreover, overexpression of CsLHT1 and CsLHT6 in Arabidopsis significantly improved the uptake of exogenously supplied 15N-glutamate and 15N-glutamine. Taken together, our findings are consistent with the involvement of CsLHT1 and CsLHT6 in amino-acid uptake from the soil, which is particularly important for tea plants grown inorganic tea plantations.

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Influence of organic cations on basic amino-acid uptake by human placental villi

Reproduction Fertility and Development ◽

10.1071/rd9951491 ◽

1995 ◽

Vol 7 (6) ◽

pp. 1491

Author(s):

RB Krishna ◽

J Dancis ◽

M Levitz

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Basic Amino Acid ◽

Amino Acid Uptake ◽

Progressive Increase ◽

Amino Acid Transporters ◽

Acid Uptake ◽

Chorionic Villi ◽

Basic Amino Acids ◽

Kinetics Of

Human placental chorionic villi were incubated for 30 min with [3H]lysine or [3H]arginine and the distribution ratios (intracellular:extracellular concentrations) were determined. The ratios remained unchanged when Na+ in Earle's buffered salt solution was replaced with Li+. When Na+ was replaced with choline there was a significant increase is distribution ratios (lysine 1.34 +/- 0.33 v. 3.99 +/- 0.15, arginine 1.95 +/- 0.37 v. 5.05 +/- 1.16). Leucine, a neutral amino acid with a Na(+)-independent transport system, was unaffected by choline substitution. The distribution ratio for alanine, which is Na(+)-dependent, was reduced (2.50 +/- 0.41 v. 1.45 +/- 0.20). Two other quarternary amines, acetyl-beta-methylcholine and tetraethylammonium chloride (TEA) caused similar increases in the distribution ratios of the basic amino acids. Hordenine, a tertiary amine, was less effective and there was little or no effect with ephedrine, a secondary amine. The choline effect was first observable at concentrations of 105 mM. With TEA, there was a progressive increase in distribution ratios beginning at 29 mM. Lysine efflux was measured after incubation of villi with lysine in Earle's buffer or choline buffer. Lysine was rapidly released to the fresh medium with 25% more retained in choline-exposed villi. The amines may cause alterations in the kinetics of basic amino-acid transporters or may modify other aspects of placental physiology permitting an increase retention of the basic amino acids.

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The role of amino acid transporters in inherited and acquired diseases

Biochemical Journal ◽

10.1042/bj20101912 ◽

2011 ◽

Vol 436 (2) ◽

pp. 193-211 ◽

Cited By ~ 109

Author(s):

Stefan Bröer ◽

Manuel Palacín

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Mammalian Cells ◽

Neuronal Excitability ◽

Tumour Progression ◽

Building Blocks ◽

Amino Acid Uptake ◽

Whole Body ◽

Amino Acid Transporters ◽

Acid Uptake

Amino acids are essential building blocks of all mammalian cells. In addition to their role in protein synthesis, amino acids play an important role as energy fuels, precursors for a variety of metabolites and as signalling molecules. Disorders associated with the malfunction of amino acid transporters reflect the variety of roles that they fulfil in human physiology. Mutations of brain amino acid transporters affect neuronal excitability. Mutations of renal and intestinal amino acid transporters affect whole-body homoeostasis, resulting in malabsorption and renal problems. Amino acid transporters that are integral parts of metabolic pathways reduce the function of these pathways. Finally, amino acid uptake is essential for cell growth, thereby explaining their role in tumour progression. The present review summarizes the involvement of amino acid transporters in these roles as illustrated by diseases resulting from transporter malfunction.

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The Regulation and Function of the L-Type Amino Acid Transporter 1 (LAT1) in Cancer

International Journal of Molecular Sciences ◽

10.3390/ijms19082373 ◽

2018 ◽

Vol 19 (8) ◽

pp. 2373 ◽

Cited By ~ 24

Author(s):

Travis Salisbury ◽

Subha Arthur

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Cancer Cells ◽

Amino Acid Uptake ◽

Essential Amino Acids ◽

Amino Acid Transporter ◽

Amino Acid Transporters ◽

Acid Uptake ◽

Cancer Pathways ◽

Acid Transporter

The progression of cancer is associated with increases in amino acid uptake by cancer cells. Upon their entry into cells through specific transporters, exogenous amino acids are used to synthesize proteins, nucleic acids and lipids and to generate ATP. The essential amino acid leucine is also important for maintaining cancer-associated signaling pathways. By upregulating amino acid transporters, cancer cells gain greater access to exogenous amino acids to support chronic proliferation, maintain metabolic pathways, and to enhance certain signal transduction pathways. Suppressing cancer growth by targeting amino acid transporters will require an in-depth understanding of how cancer cells acquire amino acids, in particular, the transporters involved and which cancer pathways are most sensitive to amino acid deprivation. L-Type Amino Acid Transporter 1 (LAT1) mediates the uptake of essential amino acids and its expression is upregulated during the progression of several cancers. We will review the upstream regulators of LAT1 and the downstream effects caused by the overexpression of LAT1 in cancer cells.

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Amino Acid Transporters on the Guard of Cell Genome and Epigenome

Cancers ◽

10.3390/cancers13010125 ◽

2021 ◽

Vol 13 (1) ◽

pp. 125

Author(s):

Uğur Kahya ◽

Ayşe Sedef Köseer ◽

Anna Dubrovska

Keyword(s):

Amino Acid ◽

Cancer Metabolism ◽

Tumor Imaging ◽

Redox Homeostasis ◽

Amino Acid Uptake ◽

Metabolic Reprogramming ◽

Tumor Evolution ◽

Amino Acid Transporters ◽

Acid Uptake ◽

Growth And Survival

Tumorigenesis is driven by metabolic reprogramming. Oncogenic mutations and epigenetic alterations that cause metabolic rewiring may also upregulate the reactive oxygen species (ROS). Precise regulation of the intracellular ROS levels is critical for tumor cell growth and survival. High ROS production leads to the damage of vital macromolecules, such as DNA, proteins, and lipids, causing genomic instability and further tumor evolution. One of the hallmarks of cancer metabolism is deregulated amino acid uptake. In fast-growing tumors, amino acids are not only the source of energy and building intermediates but also critical regulators of redox homeostasis. Amino acid uptake regulates the intracellular glutathione (GSH) levels, endoplasmic reticulum stress, unfolded protein response signaling, mTOR-mediated antioxidant defense, and epigenetic adaptations of tumor cells to oxidative stress. This review summarizes the role of amino acid transporters as the defender of tumor antioxidant system and genome integrity and discusses them as promising therapeutic targets and tumor imaging tools.

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Gamma-Glutamyl-Amino Acids as Signals for the Hormonal Regulation of Amino Acid Uptake by the Mammary Gland of the Lactating Rat

Neonatology ◽

10.1159/000242178 ◽

1985 ◽

Vol 48 (4) ◽

pp. 250-256 ◽

Cited By ~ 8

Author(s):

Juan R. Viña ◽

Inmaculada R. Puertes ◽

Juan B. Montoro ◽

Guillermo T. Saez ◽

José Viña

Keyword(s):

Amino Acids ◽

Mammary Gland ◽

Amino Acid ◽

Hormonal Regulation ◽

Amino Acid Uptake ◽

Acid Uptake ◽

Gamma Glutamyl

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Action of growth hormone in vitro on the net uptake and incorporation into protein of amino acids in muscle from intact rabbits given protein-deficient diets

British Journal Of Nutrition ◽

10.1079/bjn19760003 ◽

1976 ◽

Vol 35 (1) ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

M. R. Turner ◽

P. J. Reeds ◽

K. A. Munday

Keyword(s):

Amino Acids ◽

Growth Hormone ◽

Protein Synthesis ◽

Amino Acid ◽

De Novo ◽

Amino Acid Uptake ◽

Acid Uptake ◽

Amino Acid Incorporation ◽

Acid Incorporation

1. Net amino acid uptake, and incorporation into protein have been measured in vitro in the presence and absence of porcine growth hormone (GH) in muscle from intact rabbits fed for 5 d on low-protein (LP), protein-free (PF) or control diets.2. In muscle from control and LP animals GH had no effect on the net amino acid uptake but stimulated amino acid incorporation into protein, although this response was less in LP animals than in control animals.3. In muscle from PF animals, GH stimulated both amino acid incorporation into protein and the net amino acid uptake, a type of response which also occurs in hypophysectomized animals. The magnitude of the effect of GH on the incorporation of amino acids into protein was reduced in muscle from PF animals.4. The effect of GH on the net amino acid uptake in PF animals was completely blocked by cycloheximide; the uptake effect of GH in these animals was dependent therefore on de novo protein synthesis.5. It is proposed that in the adult the role of growth hormone in protein metabolism is to sustain cellular protein synthesis when there is a decrease in the level of substrate amino acids, similar to that which occurs during a short-term fast or when the dietary protein intake is inadequate.

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The uptake of amino acids by mouse cells (strain LS) during growth in batch culture and chemostat culture: the influence of cell growth rate

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1967.0073 ◽

1967 ◽

Vol 168 (1013) ◽

pp. 421-438 ◽

Cited By ~ 46

Keyword(s):

Amino Acids ◽

Growth Rate ◽

Amino Acid ◽

Cell Growth ◽

Glutamic Acid ◽

Batch Culture ◽

Amino Acid Uptake ◽

Essential Amino Acids ◽

Growth Yields ◽

Acid Uptake

The uptake of thirteen essential amino acids by mouse LS cells in suspension culture was determined by bacteriological assay methods. Chemostat continuous-flow cultures were used to determine the effect of different cell growth rates on the quantitative amino acid requirements for growth. The growth yields of the cells ( Y = g cell dry weight produced/g amino acid utilized) were calculated for each of the essential amino acids. A mixture of the non-essential amino acids, serine, alanine and glycine increased the cell yield from the essential amino acids. The growth yields from nearly all the essential amino acids in batch culture were increased when glutamic acid was substituted for the glutamine in the medium. The growth yields from the amino acids in batch culture were much less at the beginning than at the end of the culture. The highest efficiencies of conversion of amino acids to cell material were obtained by chemostat culture. When glutamic acid largely replaced the glutamine in the medium the conversion of amino acid nitrogen to cell nitrogen was 100 % efficient (that is, the theoretical yield was obtained) at the optimum growth rate (cell doubling time, 43 h). The maximum population density a given amino acid mixture will support can be calculated from the data. It is concluded that in several routinely used tissue culture media the cell growth is limited by the amino acid supply. In batch culture glutamine was wasted by (1) its spontaneous decomposition to pyrrolidone carboxylic acid and ammonia, and (2) its enzymic breakdown to glutamic acid and ammonia, but also glutamine was used less efficiently than glutamic acid. Study of the influence of cell growth rate on amino acid uptake rates per unit mass of cells indicated that a marked change in amino acid metabolism occurred at a specific growth rate of 0.4 day -1 (cell doubling time, 43 h). With decrease in specific growth rate below 0.4 day -1 there was a marked stimulation of amino acid uptake rate per cell and essential amino acids were consumed increasingly for functions other than synthesis of cell material.

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Action of insulin and growth hormone on protein synthesis in muscle from non-hypophysectomized rabbits

Biochemical Journal ◽

10.1042/bj1250515 ◽

1971 ◽

Vol 125 (2) ◽

pp. 515-520 ◽

Cited By ~ 13

Author(s):

P. J. Reeds ◽

K. A. Munday ◽

M. R. Turner

Keyword(s):

Amino Acids ◽

Growth Hormone ◽

Protein Synthesis ◽

Amino Acid ◽

Incubation Medium ◽

Amino Acid Uptake ◽

Diaphragm Muscle ◽

Acid Uptake

The separate effects of insulin and growth hormone on the uptake and incorporation of five amino acids into diaphragm muscle from non-hypophysectomized rabbits has been examined. Both growth hormone and insulin, when present in the medium separately, stimulated the incorporation into protein of the amino acids, leucine, arginine, valine, lysine and histidine. Insulin also stimulated amino acid uptake, but growth hormone did not. When insulin and growth hormone were present in the incubation medium together, the uptake and incorporation of valine, the only amino acid studied under these conditions, tended to be greater than the sum of the separate effects of the two hormones.

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Amino acid uptake systems in Bacteroides ruminicola

Canadian Journal of Microbiology ◽

10.1139/m79-180 ◽

1979 ◽

Vol 25 (10) ◽

pp. 1161-1168 ◽

Cited By ~ 15

Author(s):

Roselynn M. W. Stevenson

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Nitrogen Sources ◽

Amino Acid Uptake ◽

Defined Medium ◽

High Rate ◽

Transport Systems ◽

Acid Uptake ◽

Chemical Structures ◽

Kinetic Inhibition

Uptake of amino acids by Bacteroides ruminicola was observed in cells grown in a complete defined medium, containing ammonia as the nitrogen source. A high rate of uptake occurred only in fresh medium, as an inhibitory substance, possibly acetate, apparently accumulated during growth. All amino acids except proline were taken up and incorporated into cold trichloroacetic acid precipitable material. Different patterns of incorporation and different responses to 2,4-dinitrophenol and potassium ferricyanide indicated multiple uptake systems were involved. Kinetic inhibition patterns suggested six distinct systems were present for amino acid uptake, with specificities related to the chemical structures of the amino acids. Thus, the failure of free amino acids to act as sole nitrogen sources for growth of B. ruminicola is not due to the absence of transport systems for these compounds.

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Rhizobium leguminosarum Has a Second General Amino Acid Permease with Unusually Broad Substrate Specificity and High Similarity to Branched-Chain Amino Acid Transporters (Bra/LIV) of the ABC Family

Journal of Bacteriology ◽

10.1128/jb.184.15.4071-4080.2002 ◽

2002 ◽

Vol 184 (15) ◽

pp. 4071-4080 ◽

Cited By ~ 76

Author(s):

A. H. F. Hosie ◽

D. Allaway ◽

C. S. Galloway ◽

H. A. Dunsby ◽

P. S. Poole

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Rhizobium Leguminosarum ◽

Binding Protein ◽

Amino Acid Transporters ◽

Acid Uptake ◽

Amino Acid Permease ◽

Branched Chain Amino Acid ◽

General Amino Acid Permease ◽

Branched Chain

ABSTRACT Amino acid uptake by Rhizobium leguminosarum is dominated by two ABC transporters, the general amino acid permease (Aap) and the branched-chain amino acid permease (BraRl). Characterization of the solute specificity of BraRl shows it to be the second general amino acid permease of R. leguminosarum. Although BraRl has high sequence identity to members of the family of hydrophobic amino acid transporters (HAAT), it transports a broad range of solutes, including acidic and basic polar amino acids (l-glutamate, l-arginine, and l-histidine), in addition to neutral amino acids (l-alanine and l-leucine). While amino and carboxyl groups are required for transport, solutes do not have to be α-amino acids. Consistent with this, BraRl is the first ABC transporter to be shown to transport γ-aminobutyric acid (GABA). All previously identified bacterial GABA transporters are secondary carriers of the amino acid-polyamine-organocation (APC) superfamily. Also, transport by BraRl does not appear to be stereospecific as d amino acids cause significant inhibition of uptake of l-glutamate and l-leucine. Unlike all other solutes tested, l-alanine uptake is not dependent on solute binding protein BraCRl. Therefore, a second, unidentified solute binding protein may interact with the BraDEFGRl membrane complex during l-alanine uptake. Overall, the data indicate that BraRl is a general amino acid permease of the HAAT family. Furthermore, BraRl has the broadest solute specificity of any characterized bacterial amino acid transporter.

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