Flashcards: Integral membrane proteins

A photosynthetic reaction centre is a complex of several proteins, pigments and other co-factors that together execute the primary energy conversion reactions of photosynthesis.

Aquaporins are integral membrane proteins from a larger family of major intrinsic proteins (MIP) that form pores in the membrane of biological cells.

L-Monoamine oxidases (MAO) (EC 1.4.3.4) are a family of enzymes that catalyze the oxidation of monoamines.

Bcl-2 (B-cell lymphoma 2), encoded in humans by the BCL2 gene, is the founding member of the Bcl-2 family of regulator proteins that regulate cell death (apoptosis), by either inducing (pro-apoptotic) or inhibiting (anti-apoptotic) apoptosis.

The cytochrome b6f complex (plastoquinol—plastocyanin reductase; EC 1.10.99.1) is an enzyme found in the thylakoid membrane in chloroplasts of plants, cyanobacteria, and green algae, that catalyze the transfer of electrons from plastoquinol to plastocyanin.

The enzyme cytochrome c oxidase or Complex IV, EC 1.

ATPases (EC 3.6.1.3, adenylpyrophosphatase, ATP monophosphatase, triphosphatase, SV40 T-antigen, adenosine 5'-triphosphatase, ATP hydrolase, complex V (mitochondrial electron transport), (Ca2+ + Mg2+)-ATPase, HCO3−-ATPase, adenosine triphosphatase) are a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion.

Cyclooxygenase (COX), officially known as prostaglandin-endoperoxide synthase (PTGS), is an enzyme (specifically, a family of isozymes, EC 1.14.99.1) that is responsible for formation of prostanoids, including thromboxane and prostaglandins such as prostacyclin.

G protein–coupled receptors (GPCRs) which are also known as seven-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptor, and G protein–linked receptors (GPLR), constitute a large protein family of receptors, that sense molecules outside the cell and activate inside signal transduction pathways and, ultimately, cellular responses.

The epithelial sodium channel (short: ENaC, also: amiloride-sensitive sodium channel) is a membrane-bound ion-channel that is selectively permeable to Na+ ions and that is assembled as a heterotrimer composed of three homologous subunits α, β, and γ or δ, β, and γ.

A glycophorin is a sialoglycoprotein of the membrane of a red blood cell.

ATP synthase (EC 3.6.3.14) is an important enzyme that creates the energy storage molecule adenosine triphosphate (ATP).

Complex I (EC 1.6.5.3) (also referred to as NADH:ubiquinone oxidoreductase or, especially in the context of the human protein, NADH dehydrogenase is an enzyme of the respiratory chains of myriad organisms from bacteria to humans that falls under the H+ or Na+-translocating NADH Dehydrogenase (NDH) Family (TC# 3.D.1), a member of the Na+ transporting Mrp superfamily. It catalyzes the transfer of electrons from NADH to coenzyme Q10 (CoQ10) and, in eukaryotes, it is located in the inner mitochondrial membrane. NADH:ubiquinone oxidoreductases type I of bacteria and of eukaryotic mitochondria and chloroplasts couple electron transfer to the electrogenic transport of protons or Na+. It is one of the "entry enzymes" of cellular respiration or oxidative phosphorylation in the mitochondria. The Com

Glucose transporters are a wide group of membrane proteins that facilitate the transport of glucose over a plasma membrane.

In molecular biology Caveolins are a family of integral membrane proteins that are the principal components of caveolae membranes and involved in receptor-independent endocytosis.

Inwardly rectifying potassium channels (Kir, IRK) are a specific subset of potassium (K+) selective ion channels.

Chloride channels are a superfamily of poorly understood ion channels specific for chloride.

Methane monooxygenase, or MMO, is an enzyme capable of oxidizing the C-H bond in methane as well as other alkanes.

Gramicidin is a heterogeneous mixture of three antibiotic compounds, gramicidins A, B and C, making up 80%, 6%, and 14%, respectively, all of which are obtained from the soil bacterial species Bacillus brevis and called collectively gramicidin D.

The alternative oxidase (AOX) is an enzyme that forms part of the electron transport chain in mitochondria of different organisms Proteins homologous to the mitochondrial oxidase have also been identified in bacterial genomes.

Plastid terminal oxidase or plastoquinol terminal oxidase (PTOX) is an enzyme that resides on the thylakoid membranes of plant and algae chloroplasts and on the membranes of cyanobacteria.

Pannexins (from Greek 'παν' — all, and from Latin 'nexus' — connection) are a family of vertebrate proteins identified by their homology to the invertebrate innexins.

Tetraspanins are a family of membrane proteins found in all multicellular eukaryotes.

Cation diffusion facilitators (CDFs) are integral membrane proteins that increase tolerance to divalent metal ions such as cadmium, zinc, and cobalt.

The Formate-Nitrite Transporter (FNT) Family (TC# 1.A.16) is a family of homologous transmembrane proteins belonging to the Major Intrinsic Protein (MIP) Superfamily.

Members of the Small Conductance Mechanosensitive Ion Channel (MscS) Family (TC# 1.A.23) provide protection against hypo-osmotic shock in bacteria, responding both to stretching of the cell membrane and to membrane depolarization.

The Nucleobase:Cation Symporter-2 (NCS2) Family, also called the Nucleobase/Ascorbate Transporter (NAT) Family, consists of over 1000 sequenced proteins derived from gram-negative and gram-positive bacteria, archaea, fungi, plants and animals.

The L-type calcium channel (also known as the dihydropyridine channel, or DHP channel) is part of the high-voltage activated family of voltage-dependent calcium channel.

Calcium release-activated channels (CRAC) are specialized plasma membrane Ca2+ ion channels.

StAR-related lipid transfer domain protein 3 (STARD3) also known as metastatic lymph node 64 protein (MLN64) is a late endosomal integral membrane protein involved in cholesterol transport.

The medial orbital gyrus presents a well-marked antero-posterior sulcus, the olfactory sulcus, for the olfactory tract.

The Matrix-2 (M2) protein is a proton-selective ion channel protein, integral in the viral envelope of the influenza A virus.

Scramblase is a protein responsible for the translocation of phospholipids between the two monolayers of a lipid bilayer of a cell membrane.

The interleukin-2 receptor (IL-2R) is a heterotrimeric protein expressed on the surface of certain immune cells, such as lymphocytes, that binds and responds to a cytokine called IL-2.

Sec61 is an endoplasmic reticulum (ER) membrane protein translocator (aka translocon).

Talin is a high-molecular-weight cytoskeletal protein concentrated at regions of cell–substratum contact and, in lymphocytes, at cell–cell contacts.

Nitrate reductases are molybdoenzymes that reduce nitrate (NO−3) to nitrite (NO−2).

The Polycystin Cation Channel (PCC) Family (TC# 1.A.5) consists of several transporters ranging in size from 500 to over 4000 amino acyl residues (aas) in length and exhibiting between 5 and 18 transmembrane segments (TMSs).

The K+ Transporter (Trk) Family is a member of the voltage-gated ion channel (VIC) superfamily.

The ryanodine-inositol 1,4,5-triphosphate receptor Ca2+ channel (RIR-CaC) family (TC# 1.A.3) consists of several receptor proteins exhibiting 4 to 6 transmembrane segments (TMSs), although ryanodine receptor Ca2+ release channel (RyR2; TC# 1.A.3.1.1), of Homo sapiens exhibits 10 TMSs.

The transient receptor potential Ca2+ channel (TRP-CC) family (TC# 1.A.4) is a member of the voltage-gated ion channel (VIC) superfamily and consists of cation channels conserved from worms to humans.

The ATP-gated P2X Receptor Cation Channel (P2X Receptor) Family (TC# 1.A.7) consists of cation-permeable ligand gated ion channels that open in response to the binding of extracellular adenosine 5'-triphosphate (ATP).

The T-cell receptor, or TCR, is a molecule found on the surface of T cells, or T lymphocytes, that is responsible for recognizing fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules.

Carnitine O-palmitoyltransferase (also called carnitine palmitoyltransferase) is a mitochondrial transferase enzyme (EC 2.3.1.21) involved in the metabolism of palmitoylcarnitine into palmitoyl-CoA.

The Bcl-2 Family (TC# 1.A.21) consists of apoptosis regulator Bcl-2 and its homologues.

Innexins (TC# 1.A.25), or gap junction proteins, are structurally related transmembrane proteins that assemble to form invertebrate gap junctions.

The Large Conductance Mechanosensitive Ion Channel (MscL) Family (TC# 1.A.22) consists of pore-forming membrane proteins that are responsible for translating physical forces applied to cell membranes into electrophysiological activities.

In molecular biology, the Signal Peptide Peptidase (SPP) is a type of protein that specifically cleaves parts of other proteins.

Voltage-gated ion channels are a class of transmembrane proteins that form ion channels that are activated by changes in the electrical membrane potential near the channel.

The olfactory tubercle (OT, tuberculum olfactorium) is a multi-sensory processing center in the olfactory cortex that plays a role in reward behaviors.

The P-type ATPases, also known as E1-E2 ATPases, are a large group of evolutionarily related ion and lipid pumps that are found in bacteria, archaea, and eukaryotes.

Members of the Neurotransmitter:Sodium Symporter (NSS) family (TC# 2.A.22) catalyze uptake of a variety of neurotransmitters, amino acids, osmolytes and related nitrogenous substances by a solute:Na+ symport mechanism.

The P-type calcium channel is a type of voltage-dependent calcium channel.

The Q-type calcium channel is a type of voltage-dependent calcium channel.

The Amino Acid-Polyamine-Organocation (APC) Family (TC# 2.A.3) of transport proteins includes members that function as solute:cation symporters and solute:solute antiporters.

Members of the Alanine or Glycine:Cation Symporter (AGCS) Family (TC# 2.A.25) transport alanine and/or glycine in symport with Na+ and or H+.

The amino acid-polyamine-organocation (APC) superfamily is the second largest superfamily of secondary carriers currently known.

The sulfate permease (SulP) family (TC# 2.A.53) is a member of the large APC superfamily of secondary carriers.

Diacylglycerol kinase (DGK or DAGK) is a family of enzymes that catalyzes the conversion of diacylglycerol (DAG) to phosphatidic acid (PA) utilizing ATP as a source of the phosphate.

The interferon-gamma receptor (IFNGR) is a receptor that binds interferon-γ, the sole member of interferon type II.

Proteins of the Betaine/Carnitine/Choline Transporter (BCCT) family (TC# 2.A.15) are found in Gram-negative and Gram-positive bacteria and archaea.

The Nucleobase:Cation Symporter-1 (NCS1) Family (TC# 2.A.39) consists of over 1000 currently sequenced proteins derived from Gram-negative and Gram-positive bacteria, archaea, fungi and plants.

Members of the Solute:Sodium Symporter (SSS) Family (TC# 2.A.21) catalyze solute:Na+ symport.

The Calcium-Dependent Chloride Channel (Ca-ClC) Family (TC# 1.A.17) consists of eukaryotic proteins that are required for normal electrolyte and fluid secretion, olfactory perception, and neuronal and smooth muscle excitability in animals.

The Membrane Attack Complex/Perforin (MACPF) superfamily, sometimes referred to as the MACPF/CDC superfamily, is named after a domain that is common to the membrane attack complex (MAC) proteins of the complement system (C6, C7, C8α, C8β and C9) and perforin (PF).

The Disufide bond oxidoreductase D (DsbD) family is a member of the Lysine Exporter (LysE) Superfamily.

Na+/H+ antiporter A (NhaA) family (TC# 2.A.33) contains a number of bacterial sodium-proton antiporter (SPAP) proteins.

The Nicotinamide Ribonucleoside (NR) Uptake Permease (PnuC) Family (TC# 4.B.1) is a family of transmembrane transporters that is part of the TOG superfamily.

The p-aminobenzoyl-glutamate transporter (AbgT) family (TC# 2.A.68) is a family of transporter proteins belonging to the ion transporter (IT) superfamily.

Sodium/proton antiporters are essential secondary-active transporters for sodium and pH homeostasis.

The H+-translocating F420H2 Dehydrogenase (F420H2DH) Family (TC# 3.D.9) is a member of the Na+ transporting Mrp superfamily.

Ceramide synthase 5 (CerS5) is the enzyme encoded in humans by the CERS5 gene.

Ceramide synthase 4 (CerS4) is an enzyme that in humans is encoded by the CERS4 gene and is one of the least studied of the ceramide synthases.