scholarly journals Transporter oligomerization: form and function

2016 ◽  
Vol 44 (6) ◽  
pp. 1737-1744 ◽  
Author(s):  
Yilmaz Alguel ◽  
Alexander D. Cameron ◽  
George Diallinas ◽  
Bernadette Byrne
Keyword(s):  
Membrane Proteins ◽  
Aspergillus Nidulans ◽  
Membrane Trafficking ◽  
Transport Protein ◽  
Integral Membrane Proteins ◽  
Structural Basis ◽  
Protein Oligomerization ◽  
Form And Function ◽  
The Individual ◽  
And Function

Transporters are integral membrane proteins with central roles in the efficient movement of molecules across biological membranes. Many transporters exist as oligomers in the membrane. Depending on the individual transport protein, oligomerization can have roles in membrane trafficking, function, regulation and turnover. For example, our recent studies on UapA, a nucleobase ascorbate transporter, from Aspergillus nidulans, have revealed both that dimerization of this protein is essential for correct trafficking to the membrane and the structural basis of how one UapA protomer can affect the function of the closely associated adjacent protomer. Here, we review the roles of oligomerization in many particularly well-studied transporters and transporter families.

How Do Lipids Affect the Structure and Function of Integral Membrane Proteins

2012 ◽  
Vol 28 (11) ◽  
pp. 866
Author(s):  
Jie HENG ◽  
Yan WU ◽  
Xianping WANG ◽  
Kai ZHANG
Keyword(s):  
Membrane Proteins ◽  
Structure And Function ◽  
Integral Membrane Proteins ◽  
And Function

scholarly journals Design principles of hair-like structures as biological machines

2018 ◽  
Vol 15 (142) ◽  
pp. 20180206 ◽  
Author(s):  
Madeleine Seale ◽  
Cathal Cummins ◽  
Ignazio Maria Viola ◽  
Enrico Mastropaolo ◽  
Naomi Nakayama
Keyword(s):  
Mechanical Properties ◽  
Surface Area ◽  
Large Surface Area ◽  
Structural Basis ◽  
Basic Design ◽  
Form And Function ◽  
Mechanical Unit ◽  
Wide Range ◽  
Range Of Functions ◽  
And Function

Hair-like structures are prevalent throughout biology and frequently act to sense or alter interactions with an organism's environment. The overall shape of a hair is simple: a long, filamentous object that protrudes from the surface of an organism. This basic design, however, can confer a wide range of functions, owing largely to the flexibility and large surface area that it usually possesses. From this simple structural basis, small changes in geometry, such as diameter, curvature and inter-hair spacing, can have considerable effects on mechanical properties, allowing functions such as mechanosensing, attachment, movement and protection. Here, we explore how passive features of hair-like structures, both individually and within arrays, enable diverse functions across biology. Understanding the relationships between form and function can provide biologists with an appreciation for the constraints and possibilities on hair-like structures. Additionally, such structures have already been used in biomimetic engineering with applications in sensing, water capture and adhesion. By examining hairs as a functional mechanical unit, geometry and arrangement can be rationally designed to generate new engineering devices and ideas.

scholarly journals Structural basis for spectrin recognition by ankyrin

Blood ◽  
2010 ◽  
Vol 115 (20) ◽  
pp. 4093-4101 ◽  
Author(s):  
Jonathan J. Ipsaro ◽  
Alfonso Mondragón
Keyword(s):  
Membrane Proteins ◽  
Structural Model ◽  
Membrane Integrity ◽  
Adaptor Protein ◽  
Principal Component ◽  
Structural Basis ◽  
Protein Protein Interaction ◽  
The Individual ◽  
Spectrin Repeats

Maintenance of membrane integrity and organization in the metazoan cell is accomplished through intracellular tethering of membrane proteins to an extensive, flexible protein network. Spectrin, the principal component of this network, is anchored to membrane proteins through the adaptor protein ankyrin. To elucidate the atomic basis for this interaction, we determined a crystal structure of human βI-spectrin repeats 13 to 15 in complex with the ZU5-ANK domain of human ankyrin R. The structure reveals the role of repeats 14 to 15 in binding, the electrostatic and hydrophobic contributions along the interface, and the necessity for a particular orientation of the spectrin repeats. Using structural and biochemical data as a guide, we characterized the individual proteins and their interactions by binding and thermal stability analyses. In addition to validating the structural model, these data provide insight into the nature of some mutations associated with cell morphology defects, including those found in human diseases such as hereditary spherocytosis and elliptocytosis. Finally, analysis of the ZU5 domain suggests it is a versatile protein-protein interaction module with distinct interaction surfaces. The structure represents not only the first of a spectrin fragment in complex with its binding partner, but also that of an intermolecular complex involving a ZU5 domain.

scholarly journals Size Comparisons among Integral Membrane Transport Protein Homologues in Bacteria, Archaea, and Eucarya

2001 ◽  
Vol 183 (3) ◽  
pp. 1012-1021 ◽  
Author(s):  
Yong Joon Chung ◽  
Christel Krueger ◽  
David Metzgar ◽  
Milton H. Saier
Keyword(s):  
Membrane Proteins ◽  
Membrane Transport ◽  
Molecular Mechanisms ◽  
Transport Protein ◽  
Integral Membrane Proteins ◽  
The Family ◽  
Domains Of Life ◽  
Secondary Carriers ◽  
Average Size ◽  
Significant Size

ABSTRACT Integral membrane proteins from over 20 ubiquitous families of channels, secondary carriers, and primary active transporters were analyzed for average size differences between homologues from the three domains of life: Bacteria, Archaea, andEucarya. The results showed that while eucaryotic homologues are consistently larger than their bacterial counterparts, archaeal homologues are significantly smaller. These size differences proved to be due primarily to variations in the sizes of hydrophilic domains localized to the N termini, the C termini, or specific loops between transmembrane α-helical spanners, depending on the family. Within the Eucarya domain, plant homologues proved to be substantially smaller than their animal and fungal counterparts. By contrast, extracytoplasmic receptors of ABC-type uptake systems inArchaea proved to be larger on average than those of their bacterial homologues, while cytoplasmic enzymes from different organisms exhibited little or no significant size differences. These observations presumably reflect evolutionary pressure and molecular mechanisms that must have been operative since these groups of organisms diverged from each other.

Religious Ideas and Social Action in Gurage Bond-Friendship

Africa ◽  
1963 ◽  
Vol 33 (3) ◽  
pp. 198-208 ◽  
Author(s):  
William A. Shack
Keyword(s):  
Social Action ◽  
Voluntary Association ◽  
Common Theme ◽  
Form And Function ◽  
The Individual ◽  
Opening Paragraph ◽  
And Function

Opening ParagraphInstitutions of bond-friendship as a form of voluntary association exist in many societies and, when viewed cross-tribally, they show considerable variation both in form and function.1 Even so, variations in the order of bond-friendship associations seem related to a common theme: namely, that there is an exchange of goods and/or services between parties to a ritual covenant that is reinforced by supernatural sanctions; and that protestations of mutual goodwill, together with calling for imprecations of evil to befall the individual who breaks the agreement, are elements which bind the covenant.

scholarly journals A comprehensive guide to the ROMK potassium channel: form and function in health and disease

2009 ◽  
Vol 297 (4) ◽  
pp. F849-F863 ◽  
Author(s):  
Paul A. Welling ◽  
Kevin Ho
Keyword(s):  
Potassium Channel ◽  
Molecular Mechanisms ◽  
Atomic Level ◽  
Structural Basis ◽  
Potassium Homeostasis ◽  
Form And Function ◽  
Founding Member ◽  
Channel Form ◽  
Health And Disease ◽  
And Function

The discovery of the renal outer medullary K+channel (ROMK, Kir1.1), the founding member of the inward-rectifying K+channel (Kir) family, by Ho and Hebert in 1993 revolutionized our understanding of potassium channel biology and renal potassium handling. Because of the central role that ROMK plays in the regulation of salt and potassium homeostasis, considerable efforts have been invested in understanding the underlying molecular mechanisms. Here we provide a comprehensive guide to ROMK, spanning from the physiology in the kidney to the organization and regulation by intracellular factors to the structural basis of its function at the atomic level.

scholarly journals Scratching the surface: native mass spectrometry of peripheral membrane protein complexes

2020 ◽  
Vol 48 (2) ◽  
pp. 547-558 ◽  
Author(s):  
Cagla Sahin ◽  
Deseree J. Reid ◽  
Michael T. Marty ◽  
Michael Landreh
Keyword(s):  
Mass Spectrometry ◽  
Membrane Proteins ◽  
Membrane Protein ◽  
Lipid Vesicles ◽  
Native Mass Spectrometry ◽  
Integral Membrane Proteins ◽  
Structural Basis ◽  
Lipid Interactions ◽  
Native Ms ◽  
Peripheral Membrane Protein

A growing number of integral membrane proteins have been shown to tune their activity by selectively interacting with specific lipids. The ability to regulate biological functions via lipid interactions extends to the diverse group of proteins that associate only peripherally with the lipid bilayer. However, the structural basis of these interactions remains challenging to study due to their transient and promiscuous nature. Recently, native mass spectrometry has come into focus as a new tool to investigate lipid interactions in membrane proteins. Here, we outline how the native MS strategies developed for integral membrane proteins can be applied to generate insights into the structure and function of peripheral membrane proteins. Specifically, native MS studies of proteins in complex with detergent-solubilized lipids, bound to lipid nanodiscs, and released from native-like lipid vesicles all shed new light on the role of lipid interactions. The unique ability of native MS to capture and interrogate protein–protein, protein–ligand, and protein–lipid interactions opens exciting new avenues for the study of peripheral membrane protein biology.

The protein translocation machinery of the endoplasmic reticulum

1982 ◽  
Vol 300 (1099) ◽  
pp. 225-228 ◽  
Keyword(s):  
Endoplasmic Reticulum ◽  
Membrane Proteins ◽  
Rough Endoplasmic Reticulum ◽  
Protein Translocation ◽  
Signal Sequence ◽  
Integral Membrane Proteins ◽  
Multiple Copies ◽  
And Function ◽  
Lysosomal Proteins

The rough endoplasmic reticulum (r.e.r.) has been postulated to possess a single translation-coupled translocation system (in multiple copies) that effects signal sequence-mediated translocation of all secretory and lysosomal proteins and integration of all integral membrane proteins whose port of entry is the rough endoplasmic reticulum (G. Blobel 1980 Proc. natn. Acad. Sci. U.S.A. 77, 1496—1500). Two proteins have been isolated that are components of the r.e.r. translocation system. Their properties and function in protein translocation across and integration into membranes are discussed.

Product Resynthesis: Knowledge Discovery of the Value of End-of-Life Assemblies and Subassemblies

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Sung Woo Kang ◽  
Chinmay Sane ◽  
Nitish Vasudevan ◽  
Conrad S. Tucker
Keyword(s):  
End Of Life ◽  
Waste Treatment ◽  
Consumer Electronics ◽  
Mixed Integer ◽  
Form And Function ◽  
Integer Linear Model ◽  
Enterprise Level ◽  
The Individual ◽  
And Function ◽  
Multiple Domains

The trends of increasing waste and comparatively low growth of waste treatment methodologies have created the need for better utilization of the products we deem unfit for use. The options available for utilizing end-of-life (EOL) products are currently restricted to reusing, recycling, remanufacturing, and permanent disposal. In this work, the authors propose a new EOL option called resynthesis that utilizes existing waste from EOL products in a novel way through the synthesis of assemblies/subassemblies across multiple domains (i.e., consumer electronics, health care, automotive, etc.). The resynthesis of assemblies/subassemblies is achieved by quantifying their similarities (form and function) across multiple domains. A mixed-integer linear model is developed to determine the optimal EOL strategy for each component/subassembly. As a means of verifying the EOL decision, the value of the “new” resynthesized product is compared with the value that would be derived if the individual subassemblies were reused, remanufactured, recycled, or disposed. A case study involving an electronic mouse is used to validate the proposed methodology and to demonstrate its practicality as an alternate enterprise level EOL option.

Sign in / Sign up

Export Citation Format

Share Document