The sarcoplasmic Ca2+-ATPase: design of a perfect chemi-osmotic pump.

01:58 EDT 1st September 2015 | BioPortfolio

Summary of "The sarcoplasmic Ca2+-ATPase: design of a perfect chemi-osmotic pump."

The sarcoplasmic (SERCA 1a) Ca2+-ATPase is a membrane protein abundantly present in skeletal mucles where it functions as an indispensable component of the excitation-contraction coupling, being at the expense of ATP hydrolysis involved in Ca2+/H+ exchange with a high thermodynamic efficiency across the sarcoplasmic reticulum membrane. The transporter serves as a prototype of a whole family of cation transporters, the P-type ATPases, which in addition to Ca2+ transporting proteins count Na+, K+-ATPase and H+, K+-, proton- and heavy metal transporting ATPases as prominent members. The ability in recent years to produce and analyze at atomic (2.3-3 A) resolution 3D-crystals of Ca2+-transport intermediates of SERCA 1a has meant a breakthrough in our understanding of the structural aspects of the transport mechanism. We describe here the detailed construction of the ATPase in terms of one membraneous and three cytosolic domains held together by a central core that mediates coupling between Ca2+-transport and ATP hydrolysis. During turnover, the pump is present in two different conformational states, E1 and E2, with a preference for the binding of Ca2+ and H+, respectively. We discuss how phosphorylated and non-phosphorylated forms of these conformational states with cytosolic, occluded or luminally exposed cation-binding sites are able to convert the chemical energy derived from ATP hydrolysis into an electrochemical gradient of Ca2+ across the sarcoplasmic reticulum membrane. In conjunction with these basic reactions which serve as a structural framework for the transport function of other P-type ATPases as well, we also review the role of the lipid phase and the regulatory and thermodynamic aspects of the transport mechanism.

Affiliation

Centre for Membrane Pumps in Cells and Disease - PUMPKIN, Danish National Research Foundation, Denmark.

Journal Details

This article was published in the following journal.

Name: Quarterly reviews of biophysics
ISSN: 1469-8994
Pages: 1-66

Links

PubMed Articles [6865 Associated PubMed Articles listed on BioPortfolio]

Role of vacuolar-type proton ATPase in signal transduction.

The vacuolar H(+)-ATPase (V-ATPase) was first identified as an electrogenic proton pump that acidifies the lumen of intra- and extracellular compartments. The acidic pH generated by V-ATPase is import...

Sarcoplasmic reticulum Ca(2+) ATPase pump is a major regulator of glucose transport in the healthy and diabetic heart.

Despite intensive research, the pathways that mediate calcium (Ca(2+))-stimulated glucose transport in striated muscle remain elusive. Since the sarcoplasmic reticulum calcium ATPase (SERCA) pump tigh...

Lung Edema Clearance: Relevance to Patients with Lung Injury.

Pulmonary edema clearance is necessary for patients with lung injury to recover and survive. The mechanisms regulating edema clearance from the lungs are distinct from the factors contributing edema f...

Proton pump (H(+)/K(+)-ATPase) expression in human larynx.

The goal of our study was to investigate and to identify the existence of proton pump in different parts of larynx. The presence of acidic content in this area is known to be connected to several lary...

Assessing Ca2+-removal pathways in cardiac myocytes.

The decline of an intracellular calcium ([Ca(2+)]i) transient during a single excitation-contraction coupling (ECC) cycle reflects the combined activity of the sarcoplasmic reticulum Ca(2+)-ATPase (SE...

Clinical Trials [1042 Associated Clinical Trials listed on BioPortfolio]

Influence of Pantoprazole on Human Myocardial Contractility at Patients With Congestive Heart Failure

Recently literature revealed facts, that show H+/K+ ATPase expression is not limited tot he stomach. H+/K+ ATPase was also found in smooth muscle cells and in other tissues (McCabe, R.D. e...

Measurements of Colloid Osmotic Pressure in Interstitial Fluid and Plasma in Healthy and Sick Children

The purpose of this study is to measure colloid osmotic pressure in interstitial fluid and plasma in healthy children under two years, in asphyxiated babies and in children undergoing hear...

Evaluation of the Reliability and Usability of the Reusable "BrownieForSymphony" Pump Set in Home Use

The overall purpose of this study is to evaluate the reliability and usability of the reusable BrownieForSymphony pump set in home use. The primary objectives of this study is to asses an...

Pilot Study of the Addition of Osmotic Dilators to Preparation Prior to Labor Induction Abortion

One the day prior to medical abortion (labor induction) in the second trimester, insertion of osmotic dilators is added to the routine procedures. The study is to see whether the addition...

Measurement of Colloid Osmotic Pressure in Plasma and Interstitial Fluid in Children

The purpose of this study is to identify normal values of colloid osmotic pressure in interstitial fluid and plasma in healthy children between 2 and 10 years.

Medical and Biotech [MESH] Definitions

A highly effective inhibitor of gastric acid secretion used in the therapy of STOMACH ULCERS and ZOLLINGER-ELLISON SYNDROME. The drug inhibits the H(+)-K(+)-ATPase (H(+)-K(+)-EXCHANGING ATPASE) in the proton pump of GASTRIC PARIETAL CELLS.

A methylpyrrole-carboxylate from RYANIA that disrupts the RYANODINE RECEPTOR CALCIUM RELEASE CHANNEL to modify CALCIUM release from SARCOPLASMIC RETICULUM resulting in alteration of MUSCLE CONTRACTION. It was previously used in INSECTICIDES. It is used experimentally in conjunction with THAPSIGARGIN and other inhibitors of CALCIUM ATPASE uptake of calcium into SARCOPLASMIC RETICULUM.

A sesquiterpene lactone found in roots of THAPSIA. It inhibits CA(2+)-TRANSPORTING ATPASE mediated uptake of CALCIUM into SARCOPLASMIC RETICULUM.

Compounds that inhibit H(+)-K(+)-EXCHANGING ATPASE. They are used as ANTI-ULCER AGENTS and sometimes in place of HISTAMINE H2 ANTAGONISTS for GASTROESOPHAGEAL REFLUX.

Compounds that contain benzimidazole joined to a 2-methylpyridine via a sulfoxide linkage. Several of the compounds in this class are ANTI-ULCER AGENTS that act by inhibiting the POTASSIUM HYDROGEN ATPASE found in the PROTON PUMP of GASTRIC PARIETAL CELLS.


Advertisement
 

Relevant Topic

Nutrition
Latest News Clinical Trials Research Drugs Reports Corporate
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...

Advertisement
 

Searches Linking to this Article