On the function of pentameric phospholamban: ion channel or storage form?
Phospholamban (PLN) is an integral membrane protein that inhibits the sarcoplasmic reticulum Ca(2+)-ATPase, thereby regulating muscle contractility. We report a combined electrochemical and theoretical study demonstrating that the pentameric PLN does not possess channel activity for conducting chloride or calcium ions across the lipid membrane. This suggests that the pentameric configuration of PLN primarily serves as a storage form for the regulatory function of muscle relaxation by the PLN monomer.
Becucci
Lucia
L
Cembran
Alessandro
A
Karim
Christine B
CB
Thomas
David D
DD
Guidelli
Rolando
R
Gao
Jiali
J
Veglia
Gianluigi
G
D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism; D007473:Ion Channels / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D000099211:Phospholamban
D002118:Calcium; D002135:Calcium-Binding Proteins; D002712:Chlorides; D007473:Ion Channels; D000099211:Phospholamban