Table transmembrane proteins

Thus, Og and cytochrome c oxidase are the final destination for the electrons derived from the oxidation of food materials. In concert with this process, cytochrome c oxidase also drives transport of protons across the inner mitochondrial membrane. These important functions are carried out by a transmembrane protein complex consisting of more than 10 subunits (Table 21.2). 

EqEi complex (22.6) an alternative term for the ATP synthase, the multiprotein complex in the inner mitochondrial membrane that uses the energy of the proton gradient to produce ATP facilitated diffusion (18.6) movement of a solute across a membrane from an area of high concentration to an area of low concentration through a transmembrane protein, or permease family (3.1) any of the eighteen vertical columns of elements in the periodic table also called a group fatty acid (15.1,18.2) any member of the family of continuous-chain carboxylic acids that generally contain... 

Table XXIV Tetraspanins Ancient Transmembrane Proteins (TSP) Haloferax volcanii archaeasoitase may be the first TSP protein. ...

One thing that is clear from the table is that in vivo assessments of renal function in humans are limited due to the need for them to be noninvasive. In contrast, in vitro cell culture models enable processes to be examined at the cellular and molecular levels where they occur. Additionally, many of the responses and processes that are measured in vivo can be similarly measured in the in vitro model. Notable among these is the measurement of sensitive biomarkers of renal injury in urine in the in vivo model and in the extracellular medium in the in vitro cell culture model. Kidney injury molecule-1 (Kim-1) is an excellent example that has been characterized by Bonventre and colleagues (Ichimura et al., 1998,2004 Han et al., 2002 Vaidya et al., 2006 Hoffmann et al., 2010). Kim-1 is a type 1 transmembrane protein that is undetectable in normal kidney tissue but is expressed at very high levels in dedifferentiated PT epithelial cells of human and rodent kidneys after either ischanic or chemically induced injury. It appears to satisfy several of the criteria for being an ideal biomarker of effect for renal injury Kim-1 is stable in urine for prolonged periods of time, it is specific to the kidneys, its expression increases markedly from a baseline of essentially zero, and its increased expression occurs early... 

TABLE 13 Transmembrane Proteins Potentially Complexed with MHC-II... 

Glucose transport across membranes occurs via a transporter protein, i.e. GLUT transporters. These transmembrane proteins bind glucose on one face of the membrane, then undergo conformational change to translocate glucose across the membrane. The different types of GLUT transporter are oudined in the table... 

ATP synthase actually consists of two principal complexes. The spheres observed in electron micrographs make up the Fj unit, which catalyzes ATP synthesis. These Fj spheres are attached to an integral membrane protein aggregate called the Fq unit. Fj consists of five polypeptide chains named a, j3, y, 8, and e, with a subunit stoichiometry ajjSaySe (Table 21.3). Fq consists of three hydrophobic subunits denoted by a, b, and c, with an apparent stoichiometry of ajbgCg.ig- Fq forms the transmembrane pore or channel through which protons move to drive ATP synthesis. The a, j3, y, 8, and e subunits of Fj contain 510, 482, 272, 146, and 50 amino acids, respectively, with a total molecular mass... 

It is possible to calculate whether a particular sequence of amino acids present in a protein is consistent with a transmembrane location. This can be done by consulting a table that hsts the hydrophobicities of each of the 20 common amino acids and the free energy val-... 

Extracellular ATP has been demonstrated to activate a depolarizing current in different neuronal and non-neuronal cell types. These receptors are also referred to as P2 receptors. The receptors can further be divided into the G-protein-coupled P2Y receptors and the ligand-gated ion channels P2X. Currently, seven P2X receptors (P2XJ-P2X- ) have been cloned (Table 3.3). The receptors exhibit between 26 and 50% overall amino-acid identities, with the highest level of conservation in the extracellular and transmembrane regions. P2X7 (also called P2Z) is the most distant member of the family. 

The 5-HTy receptor is part of the G-protein superfamily of receptors, which contains seven transmembrane regions, and its stimulation leads to an increase in cAMP production (Thomas Hagan, 2004). The 5-HT7 receptor is expressed in a number of telencephalic, diencephalic, mesencephalic, and rhombencephalic areas (Table 9.8). 

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