title: Reversal of Phospholamban Inhibition of the Sarco(endo)plasmic Reticulum Ca2+-ATPase (SERCA) Using Short, Protein-interacting RNAs and Oligonucleotide Analogs.
abstract: The sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) and phospholamban (PLN) complex regulates heart relaxation through its removal of cytosolic Ca2+during diastole. Dysfunction of this complex has been related to many heart disorders and is therefore a key pharmacological target. There are currently no therapeutics that directly target either SERCA or PLN. It has been previously reported that single-stranded DNA binds PLN with strong affinity and relieves inhibition of SERCA in a length-dependent manner. In the current article, we demonstrate that RNAs and single-stranded oligonucleotide analogs, or xeno nucleic acids (XNAs), also bind PLN strongly (Kd<10 nm) and relieve inhibition of SERCA. Affinity for PLN is sequence-independent. Relief of PLN inhibition is length-dependent, allowing SERCA activity to be restored incrementally. The improved in vivo stability of XNAs offers more realistic pharmacological potential than DNA or RNA. We also found that microRNAs (miRNAs) 1 and 21 bind PLN strongly and relieve PLN inhibition of SERCA to a greater extent than a similar length random sequence RNA mixture. This may suggest that miR-1 and miR-21 have evolved to contain distinct sequence elements that are more effective at relieving PLN inhibition than random sequences.
authors.affiliation: From the Departments of Chemistry and.
authors.forename: Kailey J
authors.initials: KJ
authors.lastname: Soller
authors.affiliation: From the Departments of Chemistry and.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.affiliation: From the Departments of Chemistry and vegli001@umn.edu.|Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455.
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Veglia
authors.affiliation: From the Departments of Chemistry and bowser@umn.edu.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Bowser
mesh_terms: D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D035683:MicroRNAs / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009841:Oligonucleotides / Q000737:chemistry* / Q000235:genetics; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000099211:Phospholamban
chemical_list: D002135:Calcium-Binding Proteins; D035683:MicroRNAs; D009841:Oligonucleotides; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D000099211:Phospholamban; C544547:MIRN1 microRNA, human; C524940:MIRN21 microRNA, human
keywords: Phospholamban (PLN); RNA-protein interaction; calcium ATPase (SERCA); cardiomyopathy; fluorescence anisotropy; microRNA (miRNA); oligonucleotide analogs; protein complex; protein-nucleic acid interaction; structure-function