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L-cystine transport

Definition

Target type: biologicalprocess

The directed movement of L-cystine (also known as dicysteine) into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. [GOC:go_curators, ISBN:0198506732]

L-cystine transport is a crucial biological process that facilitates the uptake of L-cystine, a sulfur-containing amino acid, into cells. L-cystine is a vital precursor for the synthesis of cysteine, which is essential for various cellular functions, including protein synthesis, glutathione production, and detoxification. The transport of L-cystine across cell membranes is mediated by specific transporter proteins. The primary system involved is the system xc-, an antiporter that exchanges L-cystine for glutamate. This exchange mechanism ensures that L-cystine uptake is coupled to the efflux of glutamate, maintaining cellular homeostasis. The system xc- is a sodium-independent transporter, meaning it does not require energy from the sodium gradient for its activity. The transporter is primarily located on the plasma membrane of cells, where it facilitates the bidirectional movement of L-cystine and glutamate. The activity of the system xc- is tightly regulated by various factors, including intracellular cysteine levels, oxidative stress, and the availability of glutamate. When intracellular cysteine levels are low, the system xc- becomes more active, enhancing L-cystine uptake. Conversely, high cysteine levels suppress transporter activity. The system xc- is also upregulated in response to oxidative stress, as L-cystine is a precursor for glutathione, an important antioxidant. The availability of glutamate is another critical factor influencing L-cystine transport. The system xc- requires glutamate as a substrate for the exchange reaction, and the availability of glutamate can affect the rate of L-cystine uptake. In addition to the system xc-, other transporters have been implicated in L-cystine transport, including the y+L system and the LAT1/4F2hc complex. However, the system xc- is the primary pathway for L-cystine transport in most cell types. The efficiency of L-cystine transport is crucial for maintaining cellular cysteine homeostasis and ensuring proper cellular function. Dysregulation of L-cystine transport can contribute to various pathological conditions, including neurodegenerative diseases, cancer, and cardiovascular disease.'
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Proteins (3)

ProteinDefinitionTaxonomy
Cystine/glutamate transporterA cystine/glutamate transporter that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q9UPY5]Homo sapiens (human)
Neutral amino acid transporter AA neutral amino acid transporter A that is encoded in the genome of human. [PRO:DNx, UniProtKB:P43007]Homo sapiens (human)
Neutral amino acid transporter AA neutral amino acid transporter A that is encoded in the genome of human. [PRO:DNx, UniProtKB:P43007]Homo sapiens (human)

Compounds (17)

CompoundDefinitionClassesRoles
mesalaminemesalamine : A monohydroxybenzoic acid that is salicylic acid substituted by an amino group at the 5-position.

Mesalamine: An anti-inflammatory agent, structurally related to the SALICYLATES, which is active in INFLAMMATORY BOWEL DISEASE. It is considered to be the active moiety of SULPHASALAZINE. (From Martindale, The Extra Pharmacopoeia, 30th ed)
amino acid;
aromatic amine;
monocarboxylic acid;
monohydroxybenzoic acid;
phenols
non-steroidal anti-inflammatory drug
sulfapyridinesulfapyridine : A sulfonamide consisting of pyridine with a 4-aminobenzenesulfonamido group at the 2-position.

Sulfapyridine: Antibacterial, potentially toxic, used to treat certain skin diseases.
pyridines;
substituted aniline;
sulfonamide;
sulfonamide antibiotic
antiinfective agent;
dermatologic drug;
drug allergen;
environmental contaminant;
xenobiotic
sulfasalazinesulfasalazine : An azobenzene consisting of diphenyldiazene having a carboxy substituent at the 4-position, a hydroxy substituent at the 3-position and a 2-pyridylaminosulphonyl substituent at the 4'-position.

Sulfasalazine: A drug that is used in the management of inflammatory bowel diseases. Its activity is generally considered to lie in its metabolic breakdown product, 5-aminosalicylic acid (see MESALAMINE) released in the colon. (From Martindale, The Extra Pharmacopoeia, 30th ed, p907)
hydroxyprolinehydroxyproline : A proline derivative that is proline substituted by at least one hydroxy group.

Hydroxyproline: A hydroxylated form of the imino acid proline. A deficiency in ASCORBIC ACID can result in impaired hydroxyproline formation.
4-hydroxyproline;
L-alpha-amino acid zwitterion
human metabolite;
mouse metabolite;
plant metabolite
cysteinecysteine;
cysteine zwitterion;
L-alpha-amino acid;
proteinogenic amino acid;
serine family amino acid
EC 4.3.1.3 (histidine ammonia-lyase) inhibitor;
flour treatment agent;
human metabolite
serineserine : An alpha-amino acid that is alanine substituted at position 3 by a hydroxy group.

Serine: A non-essential amino acid occurring in natural form as the L-isomer. It is synthesized from GLYCINE or THREONINE. It is involved in the biosynthesis of PURINES; PYRIMIDINES; and other amino acids.
L-alpha-amino acid;
proteinogenic amino acid;
serine;
serine family amino acid;
serine zwitterion
algal metabolite;
Escherichia coli metabolite;
human metabolite;
mouse metabolite;
Saccharomyces cerevisiae metabolite
glutamineglutamine : An alpha-amino acid that consists of butyric acid bearing an amino substituent at position 2 and a carbamoyl substituent at position 4.

Glutamine: A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.

L-glutamine : An optically active form of glutamine having L-configuration.
amino acid zwitterion;
glutamine;
glutamine family amino acid;
L-alpha-amino acid;
polar amino acid zwitterion;
proteinogenic amino acid
EC 1.14.13.39 (nitric oxide synthase) inhibitor;
Escherichia coli metabolite;
human metabolite;
metabolite;
micronutrient;
mouse metabolite;
nutraceutical;
Saccharomyces cerevisiae metabolite
asparagineasparagine : An alpha-amino acid in which one of the hydrogens attached to the alpha-carbon of glycine is substituted by a 2-amino-2-oxoethyl group.

Asparagine: A non-essential amino acid that is involved in the metabolic control of cell functions in nerve and brain tissue. It is biosynthesized from ASPARTIC ACID and AMMONIA by asparagine synthetase. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)
amino acid zwitterion;
asparagine;
aspartate family amino acid;
L-alpha-amino acid;
proteinogenic amino acid
Escherichia coli metabolite;
human metabolite;
micronutrient;
mouse metabolite;
nutraceutical;
plant metabolite;
Saccharomyces cerevisiae metabolite
4-hydroxyphenylglycine, (s)-isomerL-4-hydroxyphenylglycine : The L-enantiomer of 4-hydroxyphenylglycine.4-hydroxyphenylglycine
quisqualic acidQuisqualic Acid: An agonist at two subsets of excitatory amino acid receptors, ionotropic receptors that directly control membrane channels and metabotropic receptors that indirectly mediate calcium mobilization from intracellular stores. The compound is obtained from the seeds and fruit of Quisqualis chinensis.non-proteinogenic alpha-amino acid
D-serineD-alpha-amino acid;
serine;
serine zwitterion
Escherichia coli metabolite;
human metabolite;
NMDA receptor agonist
gamma-glutamine-4-nitroanilidegamma-glutamine-4-nitroanilide: substrate for glutaminase B.; RN given refers to (L)-isomer
prolineproline : An alpha-amino acid that is pyrrolidine bearing a carboxy substituent at position 2.

Proline: A non-essential amino acid that is synthesized from GLUTAMIC ACID. It is an essential component of COLLAGEN and is important for proper functioning of joints and tendons.
amino acid zwitterion;
glutamine family amino acid;
L-alpha-amino acid;
proline;
proteinogenic amino acid
algal metabolite;
compatible osmolytes;
Escherichia coli metabolite;
micronutrient;
mouse metabolite;
nutraceutical;
Saccharomyces cerevisiae metabolite
serine o-sulfateL-serine O-sulfate : A non-proteinogenic L-alpha-amino acid that is the O-sulfo derivative of L-serine.

serine O-sulfate: RN given refers to (L)-isomer
L-serine derivative;
non-proteinogenic L-alpha-amino acid;
O-sulfoamino acid
homocysteic acidhomocysteic acid : A non-proteinogenic alpha-amino acid that is homocysteine in which the thiol group has benn oxidised to the corresponding sulfonic acid.

homocysteic acid: promotes growth in hypophysectomized rats; RN given refers to parent cpd

L-homocysteic acid : A homocysteic acid with L-configuration.
homocysteic acidNMDA receptor agonist
susalimodsusalimod: analogue of sulphasalazine, was designed for use in the treatment of rheumatoid arthritis
erastinerastin : A member of the class of quinazolines that is quinazolin-4(3H)-one in which the hydrogens at positions 2 and 3 are replaced by 1-{4-[(4-chlorophenoxy)acetyl]piperazin-1-yl}ethyl and 2-ethoxyphenyl groups, respectively. It is an inhibitor of voltage-dependent anion-selective channels (VDAC2 and VDAC3) and a potent ferroptosis inducer.

erastin: an antineoplastic agent; structure in first source
aromatic ether;
diether;
monochlorobenzenes;
N-acylpiperazine;
N-alkylpiperazine;
quinazolines;
tertiary carboxamide
antineoplastic agent;
ferroptosis inducer;
voltage-dependent anion channel inhibitor