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Transporter Classification Database
The Transporter Classification Database (or TCDB) is an International Union of Biochemistry and Molecular Biology (IUBMB)-approved classification system for membrane transport proteins, including ion channels. Classification The upper level of classification and a few examples of proteins with known 3D structure: 1. Channels and pores 1.A α-type channels * 1.A.1 Voltage-gated ion channel superfamily * 1.A.2 Inward-rectifier K+ channel family * 1.A.3 Ryanodine-inositol-1,4,5-trisphosphate receptor Ca2+ channel family * 1.A.4 Transient receptor potential Ca2+ channel family * 1.A.5 Polycystin cation channel family * 1.A.6 Epithelial Na+ channel family * 1.A.7 ATP-gated P2X receptor cation channel family * 1.A.8 Major intrinsic protein superfamily * 1.A.9 Neurotransmitter receptor, Cys loop, ligand-gated ion channel family * 1.A.10 Glutamate-gated ion channel family of neurotransmitter receptors * 1.A.11 Ammonium channel transporter family * 1.A.12 Intracellular chlorid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union Of Biochemistry And Molecular Biology
The International Union of Biochemistry and Molecular Biology (IUBMB) is an international non-governmental organisation concerned with biochemistry and molecular biology. Formed in 1955 as the International Union of Biochemistry (IUB), the union has presently 79 member countries and regions (as of 2020).IUBMB: the first half-century. /ref> The Union is devoted to promoting research and education in biochemistry and molecular biology throughout the world, and gives particular attention to localities where the subject is still in its early development. History The first Congress of Bioche ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testis-enhanced Gene Transfer Family
The testis-enhanced gene transcript (TEGT) family includes the testis-enhanced gene transcript proteins of mammals, which are expressed at high levels in the testis, the putative glutamate/aspartate binding proteins of plants and animals, the YccA protein of ''Escherichia coli'' and the YetJ protein of ''Bacillus subtilis''. These proteins are about 200-250 residues in length and exhibit 7 TMSs. Homology Homologues are found in a variety of Gram-negative and Gram-positive bacteria, yeast, fungi, plants, animals and viruses. The ''E. coli'' genome encodes three paralogues, YbhL, YbhM and YccA. Distant homologues found in '' Drosophilia melanogaster'' and the rat are the N-methyl-D-aspartate receptor-associated protein (NMDARAI) and the N-methyl-D-aspartate receptor glutamate binding chain, respectively. Two others are the rat neural membrane protein 35 and the ''Arabidopsis thaliana'' Bax inhibitor-1 (BI-1) protein capable of suppressing Bax-induced cell death in yeast. BI-1 On ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholemman
The FXYD protein family is a family of small membrane proteins that share a 35-amino acid signature sequence domain, beginning with the amino acid sequence PFXYD and containing 7 invariant and 6 highly conserved amino acids. The approved human gene nomenclature for the family is FXYD-domain containing ion transport regulator. It contains at least seven members in mammals. Two other family members that are not obvious orthologs of any identified mammalian FXYD protein exist in zebrafish. All these proteins share a signature sequence of six conserved amino acids comprising the FXYD motif in the NH2-terminus, and two glycines and one serine residue in the transmembrane domain. FXYD proteins are widely distributed in mammalian tissues with prominent expression in tissues that perform fluid and solute transport or that are electrically excitable. Initial functional characterization suggested that FXYD proteins act as channels or as modulators of ion channels. However, studies have reve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Transporter E
Magnesium transporters E (MgtE) are a family of transmembrane eubacterial MgtE magnesium transporters. Related regions are found also in archaeal and eukaryotic proteins. They have sizes that vary considerably from 311 residues for the ''Methanococcus thermoautotrophicum'' protein, 463 residues for a ''Synechocystis'' homologue, and 513 residues for the human homologue, SLC41A1. These proteins are capable of transporting Mg2+ and Co2+ but not Ni2+. Multiple alignments contain two highly conserved aspartates that may be involved in cation binding. Human transporters from this family are SLC41A1, SLC41A2 and SLC41A3. Structure and Mechanism The '' Bacillus firmus'' transporter and several homologues examined have strongly charged, hydrophilic N-terminal domains (cytoplasmic) followed by a hydrophobic C-terminal domain with 5 putative transmembrane α-helical spanners. A central 100 residues resembles archaeal inositol monophosphate dehydrogenases. Kehres and Maguire suggest that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Innexin
Innexins are transmembrane proteins that form gap junctions in invertebrates. Gap junctions are composed of membrane proteins that form a channel permeable to ions and small molecules connecting the cytoplasm of adjacent cells. Although gap junctions provide similar functions in all multicellular organisms, it was not known what proteins invertebrates used for this purpose until the late 1990s. While the connexin family of gap junction proteins was well-characterized in vertebrates, no homologues were found in non-chordates. Innexins or related proteins are widespread among Eumetazoa, with the exception of echinoderms. Discovery Gap junction proteins with no sequence homology to connexins were initially identified in fruit flies. It was suggested that these proteins are specific invertebrate gap junctions, and they were thus named "innexins" (invertebrate analog of connexins). They were later identified in diverse invertebrates. Invertebrate genomes may contain more than a d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connexin
Connexins (Cx)TC# 1.A.24, or gap junction proteins, are structurally related transmembrane proteins that assemble to form vertebrate gap junctions. An entirely different family of proteins, the innexins, forms gap junctions in invertebrates. Each gap junction is composed of two hemichannels, or connexons, which consist of homo- or heterohexameric arrays of connexins, and the connexon in one plasma membrane docks end-to-end with a connexon in the membrane of a closely opposed cell. The hemichannel is made of six connexin subunits, each of which consist of four transmembrane segments. Gap junctions are essential for many physiological processes, such as the coordinated depolarization of cardiac muscle, proper embryonic development, and the conducted response in microvasculature. Connexins also have non-channel dependant functions relating to cytoskeleton and cell migration. For these reasons, mutations in connexin-encoding genes can lead to functional and developmental abnormalitie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small-conductance Mechanosensitive Ion Channel
Mechanosensitive channels (MSCs), mechanosensitive ion channels or stretch-gated ion channels are membrane proteins capable of responding to mechanical stress over a wide dynamic range of external mechanical stimuli. They are present in the membranes of organisms from the three domains of life: bacteria, archaea, and eukarya. They are the sensors for a number of systems including the senses of touch, hearing and balance, as well as participating in cardiovascular regulation and osmotic homeostasis (e.g. thirst). The channels vary in selectivity for the permeating ions from nonselective between anions and cations in bacteria, to cation selective allowing passage Ca2+, K+ and Na+ in eukaryotes, and highly selective K+ channels in bacteria and eukaryotes. All organisms, and apparently all cell types, sense and respond to mechanical stimuli. MSCs function as mechanotransducers capable of generating both electrical and ion flux signals as a response to external or internal stimuli. Un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large-conductance Mechanosensitive Ion Channel
Large conductance mechanosensitive ion channels (MscLs)TC# 1.A.22 are a family of pore-forming membrane proteins that are responsible for translating stresses at the cell membrane into an electrophysiological response. MscL has a relatively large conductance, 3 nS, making it permeable to ions, water, and small proteins when opened. MscL acts as stretch-activated osmotic release valve in response to osmotic shock. History MscL was first discovered on the surface of giant ''Escherichia coli'' spheroplasts using patch-clamp technique. Subsequently, the ''Escherichia coli'' MscL (Ec-MscL) gene was cloned in 1994. Following the cloning of MscL, the crystal structure of ''Mycobacterium tuberculosis'' MscL (Tb-MscL), was obtained in its closed conformation. In addition, the crystal structure of ''Staphylococcus aureus'' MscL (Sa-MscL) and Ec-MscL have been determined using X-ray crystallography and molecular model respectively. However, some evidence suggests that the Sa-MscL structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bcl-2 Family
The Bcl-2 family (TC# 1.A.21) consists of a number of Conserved sequence, evolutionarily-conserved proteins that share Bcl-2 Sequence homology, homology (BH) domains. The Bcl-2 family is most notable for their regulation of apoptosis, a form of programmed cell death, at the mitochondrion. The Bcl-2 family proteins consists of members that either promote or inhibit apoptosis, and control apoptosis by governing mitochondrial outer membrane permeabilization (MOMP), which is a key step in the intrinsic pathway of apoptosis. A total of 25 genes in the Bcl-2 family were identified by 2008. Members of the BCL-2 family regulate apoptosis in mammals, reptiles, amphibs, fish, and other phyla of metazoan life, with exception of nematodes and insects. Their molecular structure and function, as well as their protein dynamics, are highly conserved over hundreds of millions of years in tissue forming life forms. Structure Bcl-2 family proteins have a general structure that consists of a Hydr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BNIP3
BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 is a protein found in humans that is encoded by the ''BNIP3'' gene. BNIP3 is a member of the apoptotic Bcl-2 protein family. It can induce cell death while also assisting with cell survival. Like many of the Bcl-2 family proteins, BNIP3 modulates the permeability state of the outer mitochondrial membrane by forming homo- and hetero-oligomers inside the membrane. Upregulation results in a decrease in mitochondrial potential, an increase in reactive oxygen species, mitochondrial swelling and fission, and an increase in mitochondrial turnover via autophagy. Sequence similarity with Bcl-2 family members was not detected. Humans and other animals (''Drosophila, Caenorhabditis''), as well as lower eukaryotes (''Dictyostelium, Trypanosoma, Cryptosporidium, Paramecium'') encode several BNIP3 paralogues including the human NIP3L, which induces apoptosis by interacting with viral and cellular anti-apoptosis proteins. Structure T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M2 Proton Channel
The Matrix-2 (M2) protein is a proton-selective viroporin, integral in the viral envelope of the influenza A virus. The channel itself is a homotetramer (consists of four identical M2 units), where the units are helices stabilized by two disulfide bonds, and is activated by low pH. The M2 protein is encoded on the seventh RNA segment together with the M1 protein. Proton conductance by the M2 protein in influenza A is essential for viral replication. Influenza B and C viruses encode proteins with similar function dubbed "BM2" and "CM2" respectively. They share little similarity with M2 at the sequence level, despite a similar overall structure and mechanism. Structure In influenza A virus, M2 protein unit consists of three protein segments comprising 97 amino acid residues: (i) an extracellular N-terminal domain (residues 1–23); (ii) a transmembrane segment (TMS) (residues 24–46); (iii) an intracellular C-terminal domain (residues 47–97). The TMS forms the pore of the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tic110 Family
The Chloroplast Envelope Anion Channel-forming Tic110 (Tic110) FamilyTC#1.A.18 consists of proteins of the Chloroplast membrane, inner chloroplast envelope membrane. This family consists of the inner membrane protein import apparatus, and appears to be a protein import-related anion-selective channel. It has also been designated (1) IEP110, (2) IAP100 and (3) protein import-related anion Ion channel, channel (PIRAC). Location Most of the Tic110 protein is probably in the intermembrane space. Transport across the outer and inner membranes probably occurs by two independent processes. Structure ''Arabidopsis thaliana'' Tic 110 is 996 amino acyl residues long and exhibits 2 putative Transmembrane domain, transmembrane segments (TMSs) near its N-terminus at positions 74-92 and 101-120. Biochemical analyses suggest that this protein is part of a 600 kDa complex. Tic110 has two proposed functions with naturally exclusive structures; a protein-conducting channel with 6 TMSs, and a sca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
