Anti-Phospholamban antibody

Supplementary info

This supplementary information is collated from multiple sources and compiled automatically.

Activity summary

Phospholamban abbreviated as PLN is an important regulatory protein in cardiac muscle cells often referred to interchangeably with its phosphorylated form phospho-phospholamban. This protein with a molecular mass of about 6 kDa is primarily expressed in cardiac and skeletal muscles. It functions mechanically by regulating the calcium pump (SERCA2a) in the sarcoplasmic reticulum modulating calcium uptake during muscle relaxation. In its unphosphorylated state phospholamban inhibits the activity of SERCA2a reducing calcium uptake and affecting muscle contractility.

Biological function summary

Phospholamban serves as an important mediator in the control of cardiac muscle contraction and relaxation. It is a component of the calcium cycling process within heart cells and associates directly with SERCA2a to form a regulatory complex. This association allows phospholamban to influence calcium homeostasis significantly affecting myocardial contractility and relaxation. Phosphorylation of phospholamban typically induced by beta-adrenergic signaling results in diminished interaction with SERCA2a enhancing calcium uptake into the sarcoplasmic reticulum.

Pathways

Several important pathways involve phospholamban including the adrenergic signaling pathway in cardiomyocytes and calcium signaling pathways. Phospholamban's role in these pathways is linked with proteins like SERCA2a and Protein Kinase A (PKA). PKA phosphorylates phospholamban an important step in the beta-adrenergic cascade that leads to increased heart muscle contractility. This phosphorylation event highlights phospholamban's participation in modulating cardiac output under sympathetic nervous system influence.

Associated diseases and disorders

Phospholamban's regulation of calcium homeostasis connects it directly to conditions like heart failure and cardiomyopathy. In heart failure the dysregulation of phospholamban phosphorylation can lead to impaired cardiac function due to disrupted calcium cycling reducing cardiac output. Mutations in the phospholamban gene can lead to dilated cardiomyopathy a condition characterized by the enlargement and weakening of the heart muscle. These mutations affect the interaction with SERCA2a highlighting the role of phospholamban in maintaining cardiac muscle health.