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Membrane Transport Proteins (membrane + transport_protein)
Selected AbstractsMembrane transport proteins in health and diseaseJOURNAL OF INTERNAL MEDICINE, Issue 1 2007Article first published online: 3 JAN 200 No abstract is available for this article. [source] Membrane transport proteins in health and diseaseJOURNAL OF INTERNAL MEDICINE, Issue 1 2007A. Aperia No abstract is available for this article. [source] Kell and XK immunohistochemistry in McLeod myopathyMUSCLE AND NERVE, Issue 10 2001Hans H. Jung MD Abstract The McLeod syndrome is an X-linked neuroacanthocytosis manifesting with myopathy and progressive chorea. It is caused by mutations of the XK gene encoding the XK protein, a putative membrane transport protein of yet unknown function. In erythroid tissues, XK forms a functional complex with the Kell glycoprotein. Here, we present an immunohistochemical study in skeletal muscle of normal controls and a McLeod patient with a XK gene point mutation (C977T) using affinity-purified antibodies against XK and Kell proteins. Histological examination of the affected muscle revealed the typical pattern of McLeod myopathy including type 2 fiber atrophy. In control muscles, Kell immunohistochemistry stained sarcoplasmic membranes. XK immunohistochemistry resulted in a type 2 fiber-specific intracellular staining that was most probably confined to the sarcoplasmic reticulum. In contrast, there was only a weak background signal without a specific staining pattern for XK and Kell in the McLeod muscle. Our results demonstrate that the lack of physiological XK expression correlates to the type 2 fiber atrophy in McLeod myopathy, and suggest that the XK protein represents a crucial factor for the maintenance of normal muscle structure and function. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1346,1351, 2001 [source] Copper Homeostasis: The Role of Cellular TransportersNUTRITION REVIEWS, Issue 9 2001Edward D. Harris Ph.D. Copper transport at the cellular level is achieved by a coordinate series of interactions between passive and active membrane transport proteins, vesicles, and soluble peptides. Knowing the function of each component of this complex network has made the task of delineating the mechanism of intracellular copper homeostasis achievable. [source] Studying ion channels in undergraduate laboratoriesBIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION, Issue 6 2000Ashley Garrill Abstract This article describes an undergraduate laboratory that introduces students to ion channels and patch clamp electrophysiology. It is given in conjunction with third year biochemistry lectures on membrane transport proteins and utilises cytoplasmic droplets from Characean algae. These droplets are very easily obtainable (the typical preparation time is around ten minutes). contain abundant channel activity and significantly, readily form the high electrical resistance seals that are required for resolution of single channel events. Most students have been able to observe electrical events that are the result of conformational changes in single protein molecules. When the students are not patch clamping they are set a problem that requires them to devise a model of how several different types of channel might interact to produce a cellular response to osmotic challenge. © 2001 IUBMB. Published by Elsevier Science Ltd. All rights reserved. [source] Functional imaging: New views on lens structure and functionCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2004Paul J Donaldson SUMMARY 1.,We have developed an experimental imaging approach that allows the distribution of lens membrane proteins to be mapped with subcellular resolution over large distances as a function of fibre cell differentiation. 2.,Using this approach in the rat lens, we have localized precisely histological sites of connexin 46 cleavage, quantitatively mapped changes in gap junction distribution and fibre cell morphology and correlated these changes to differences in intercellular dye transfer. 3.,Profiling of glucose transporter isoform expression showed that lens epithelial cells express GLUT1, whereas deeper cortical fibre cells express the higher-affinity GLUT3 isoform. Near the lens periphery, GLUT3 was located in the cytoplasm of fibre cells, but it underwent a differentiation-dependent membrane insertion. 4.,Similarly, the putative adhesion protein membrane protein 20 is inserted into fibre cell membranes at the stage when the cells lose their nuclei. This redistribution is strikingly rapid in terms of fibre cell differentiation and correlates with a barrier to extracellular diffusion. 5.,Our imaging-orientated approach has facilitated new insights into the relationships between fibre cell differentiation and lens function. Taken together, our results indicate that a number of strategies are used by the lens during the course of normal differentiation to change the subcellular distribution, gross spatial location and functional properties of key membrane transport proteins. [source] |