Nucleotide dependent differences between the α-skeletal and α-cardiac actin isoforms

József Orbán, D. Lőrinczy, M. Nyitrai, G. Hild

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

The thermodynamic properties of the actin filaments prepared from cardiomyocytes were investigated with differential scanning calorimetry. This method could distinguish between the α-cardiac and α-skeletal components of the actin filaments polymerised from ADP-actin monomers by their different melting temperatures (Tm). Similar separation was not possible with filaments polymerised from ATP-actin monomers. Further analyses revealed that the activation energy (Eact) was greater for filaments of α-skeletal actin than for α-cardiac actin monomers when the filaments were polymerised from ADP-actin monomers. These results showed that the α-cardiac actin filaments were thermodynamically less stable than the filaments of α-skeletal actin and their difference was nucleotide dependent. Based on these results and considering previous observations it was concluded that the existence of two actin isoforms and their nucleotide dependent conformational differences are part of the tuning regulatory mechanism by which the cardiac muscle cells can maintain their biological function under pathological conditions.

Original languageEnglish
Pages (from-to)696-702
Number of pages7
JournalBiochemical and Biophysical Research Communications
Volume368
Issue number3
DOIs
Publication statusPublished - Apr 11 2008

Fingerprint

Actin Cytoskeleton
Actins
Protein Isoforms
Nucleotides
Monomers
Cardiac Myocytes
Activation Analysis
Differential Scanning Calorimetry
Thermodynamics
Freezing
Melting point
Muscle
Differential scanning calorimetry
Temperature
Thermodynamic properties
Tuning
Activation energy
Cells
ADP-G-actin

Keywords

  • Actin filament
  • Calorimetry
  • Nucleotides
  • Protein conformation
  • Stability
  • Thermodynamics

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Molecular Biology

Cite this

@article{8dedb7a704ca4c7da407f022a2b7fae0,
title = "Nucleotide dependent differences between the α-skeletal and α-cardiac actin isoforms",
abstract = "The thermodynamic properties of the actin filaments prepared from cardiomyocytes were investigated with differential scanning calorimetry. This method could distinguish between the α-cardiac and α-skeletal components of the actin filaments polymerised from ADP-actin monomers by their different melting temperatures (Tm). Similar separation was not possible with filaments polymerised from ATP-actin monomers. Further analyses revealed that the activation energy (Eact) was greater for filaments of α-skeletal actin than for α-cardiac actin monomers when the filaments were polymerised from ADP-actin monomers. These results showed that the α-cardiac actin filaments were thermodynamically less stable than the filaments of α-skeletal actin and their difference was nucleotide dependent. Based on these results and considering previous observations it was concluded that the existence of two actin isoforms and their nucleotide dependent conformational differences are part of the tuning regulatory mechanism by which the cardiac muscle cells can maintain their biological function under pathological conditions.",
keywords = "Actin filament, Calorimetry, Nucleotides, Protein conformation, Stability, Thermodynamics",
author = "J{\'o}zsef Orb{\'a}n and D. Lőrinczy and M. Nyitrai and G. Hild",
year = "2008",
month = "4",
day = "11",
doi = "10.1016/j.bbrc.2008.01.158",
language = "English",
volume = "368",
pages = "696--702",
journal = "Biochemical and Biophysical Research Communications",
issn = "0006-291X",
publisher = "Academic Press Inc.",
number = "3",

}

TY - JOUR

T1 - Nucleotide dependent differences between the α-skeletal and α-cardiac actin isoforms

AU - Orbán, József

AU - Lőrinczy, D.

AU - Nyitrai, M.

AU - Hild, G.

PY - 2008/4/11

Y1 - 2008/4/11

N2 - The thermodynamic properties of the actin filaments prepared from cardiomyocytes were investigated with differential scanning calorimetry. This method could distinguish between the α-cardiac and α-skeletal components of the actin filaments polymerised from ADP-actin monomers by their different melting temperatures (Tm). Similar separation was not possible with filaments polymerised from ATP-actin monomers. Further analyses revealed that the activation energy (Eact) was greater for filaments of α-skeletal actin than for α-cardiac actin monomers when the filaments were polymerised from ADP-actin monomers. These results showed that the α-cardiac actin filaments were thermodynamically less stable than the filaments of α-skeletal actin and their difference was nucleotide dependent. Based on these results and considering previous observations it was concluded that the existence of two actin isoforms and their nucleotide dependent conformational differences are part of the tuning regulatory mechanism by which the cardiac muscle cells can maintain their biological function under pathological conditions.

AB - The thermodynamic properties of the actin filaments prepared from cardiomyocytes were investigated with differential scanning calorimetry. This method could distinguish between the α-cardiac and α-skeletal components of the actin filaments polymerised from ADP-actin monomers by their different melting temperatures (Tm). Similar separation was not possible with filaments polymerised from ATP-actin monomers. Further analyses revealed that the activation energy (Eact) was greater for filaments of α-skeletal actin than for α-cardiac actin monomers when the filaments were polymerised from ADP-actin monomers. These results showed that the α-cardiac actin filaments were thermodynamically less stable than the filaments of α-skeletal actin and their difference was nucleotide dependent. Based on these results and considering previous observations it was concluded that the existence of two actin isoforms and their nucleotide dependent conformational differences are part of the tuning regulatory mechanism by which the cardiac muscle cells can maintain their biological function under pathological conditions.

KW - Actin filament

KW - Calorimetry

KW - Nucleotides

KW - Protein conformation

KW - Stability

KW - Thermodynamics

UR - http://www.scopus.com/inward/record.url?scp=39749155049&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=39749155049&partnerID=8YFLogxK

U2 - 10.1016/j.bbrc.2008.01.158

DO - 10.1016/j.bbrc.2008.01.158

M3 - Article

VL - 368

SP - 696

EP - 702

JO - Biochemical and Biophysical Research Communications

JF - Biochemical and Biophysical Research Communications

SN - 0006-291X

IS - 3

ER -