Comparing skeletal and cardiac calsequestrin structures and their calcium binding

A proposed mechanism for coupled calcium binding and protein polymerization

HaJeung Park, Yeong Il Park, EunJung Kim, Buhyun Youn, Kelly Fields, A. Dunker, ChulHee Kang

Research output: Contribution to journalArticle

102 Citations (Scopus)

Abstract

Calsequestrin, the major calcium storage protein of both cardiac and skeletal muscle, binds and releases large numbers of Ca2+ ions for each contraction and relaxation cycle. Here we show that two crystal structures for skeletal and cardiac calsequestrin are nearly superimposable not only for their subunits but also their front-to-front-type dimers. Ca2+ binding curves were measured using atomic absorption spectroscopy. This method enables highly accurate measurements even for Ca2+ bound to polymerized protein. The binding curves for both skeletal and cardiac calsequestrin were complex, with binding increases that correlated with protein dimerization, tetramerization, and oligomerization. The Ca2+ binding capacities of skeletal and cardiac calsequestrin are directly compared for the first time, with ∼80 Ca2+ ions bound per skeletal calse-questrin and ∼60 Ca2+ ions per cardiac calsequestrin, as compared with net charges for these molecules of ∼80 and ∼69, respectively. Deleting the negatively charged and disordered C-terminal 27 amino acids of cardiac calsequestrin results in a 50% reduction of its calcium binding capacity and a loss of Ca2+-dependent tetramer formation. Based on the crystal structures of rabbit skeletal muscle calsequestrin and canine cardiac calsequestrin, Ca2+ binding capacity data, and previous light-scattering data, a mechanism of Ca2+ binding coupled with polymerization is proposed.

Original languageEnglish
Pages (from-to)18026-18033
Number of pages8
JournalJournal of Biological Chemistry
Volume279
Issue number17
DOIs
StatePublished - Apr 23 2004

Fingerprint

Calsequestrin
Calcium-Binding Proteins
Polymerization
Calcium
Ions
Muscle
Skeletal Muscle
Crystal structure
Protein Multimerization
Atomic spectroscopy
Oligomerization
Proteins
Dimerization
Absorption spectroscopy
Dimers
Light scattering
Canidae
Spectrum Analysis
Myocardium
Rabbits

ASJC Scopus subject areas

  • Biochemistry

Cite this

Comparing skeletal and cardiac calsequestrin structures and their calcium binding : A proposed mechanism for coupled calcium binding and protein polymerization. / Park, HaJeung; Park, Yeong Il; Kim, EunJung; Youn, Buhyun; Fields, Kelly; Dunker, A.; Kang, ChulHee.

In: Journal of Biological Chemistry, Vol. 279, No. 17, 23.04.2004, p. 18026-18033.

Research output: Contribution to journalArticle

Park, HaJeung ; Park, Yeong Il ; Kim, EunJung ; Youn, Buhyun ; Fields, Kelly ; Dunker, A. ; Kang, ChulHee. / Comparing skeletal and cardiac calsequestrin structures and their calcium binding : A proposed mechanism for coupled calcium binding and protein polymerization. In: Journal of Biological Chemistry. 2004 ; Vol. 279, No. 17. pp. 18026-18033.
@article{9474e0dac29340c38a7856bdfe927472,
title = "Comparing skeletal and cardiac calsequestrin structures and their calcium binding: A proposed mechanism for coupled calcium binding and protein polymerization",
abstract = "Calsequestrin, the major calcium storage protein of both cardiac and skeletal muscle, binds and releases large numbers of Ca2+ ions for each contraction and relaxation cycle. Here we show that two crystal structures for skeletal and cardiac calsequestrin are nearly superimposable not only for their subunits but also their front-to-front-type dimers. Ca2+ binding curves were measured using atomic absorption spectroscopy. This method enables highly accurate measurements even for Ca2+ bound to polymerized protein. The binding curves for both skeletal and cardiac calsequestrin were complex, with binding increases that correlated with protein dimerization, tetramerization, and oligomerization. The Ca2+ binding capacities of skeletal and cardiac calsequestrin are directly compared for the first time, with ∼80 Ca2+ ions bound per skeletal calse-questrin and ∼60 Ca2+ ions per cardiac calsequestrin, as compared with net charges for these molecules of ∼80 and ∼69, respectively. Deleting the negatively charged and disordered C-terminal 27 amino acids of cardiac calsequestrin results in a 50{\%} reduction of its calcium binding capacity and a loss of Ca2+-dependent tetramer formation. Based on the crystal structures of rabbit skeletal muscle calsequestrin and canine cardiac calsequestrin, Ca2+ binding capacity data, and previous light-scattering data, a mechanism of Ca2+ binding coupled with polymerization is proposed.",
author = "HaJeung Park and Park, {Yeong Il} and EunJung Kim and Buhyun Youn and Kelly Fields and A. Dunker and ChulHee Kang",
year = "2004",
month = "4",
day = "23",
doi = "10.1074/jbc.M311553200",
language = "English",
volume = "279",
pages = "18026--18033",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "17",

}

TY - JOUR

T1 - Comparing skeletal and cardiac calsequestrin structures and their calcium binding

T2 - A proposed mechanism for coupled calcium binding and protein polymerization

AU - Park, HaJeung

AU - Park, Yeong Il

AU - Kim, EunJung

AU - Youn, Buhyun

AU - Fields, Kelly

AU - Dunker, A.

AU - Kang, ChulHee

PY - 2004/4/23

Y1 - 2004/4/23

N2 - Calsequestrin, the major calcium storage protein of both cardiac and skeletal muscle, binds and releases large numbers of Ca2+ ions for each contraction and relaxation cycle. Here we show that two crystal structures for skeletal and cardiac calsequestrin are nearly superimposable not only for their subunits but also their front-to-front-type dimers. Ca2+ binding curves were measured using atomic absorption spectroscopy. This method enables highly accurate measurements even for Ca2+ bound to polymerized protein. The binding curves for both skeletal and cardiac calsequestrin were complex, with binding increases that correlated with protein dimerization, tetramerization, and oligomerization. The Ca2+ binding capacities of skeletal and cardiac calsequestrin are directly compared for the first time, with ∼80 Ca2+ ions bound per skeletal calse-questrin and ∼60 Ca2+ ions per cardiac calsequestrin, as compared with net charges for these molecules of ∼80 and ∼69, respectively. Deleting the negatively charged and disordered C-terminal 27 amino acids of cardiac calsequestrin results in a 50% reduction of its calcium binding capacity and a loss of Ca2+-dependent tetramer formation. Based on the crystal structures of rabbit skeletal muscle calsequestrin and canine cardiac calsequestrin, Ca2+ binding capacity data, and previous light-scattering data, a mechanism of Ca2+ binding coupled with polymerization is proposed.

AB - Calsequestrin, the major calcium storage protein of both cardiac and skeletal muscle, binds and releases large numbers of Ca2+ ions for each contraction and relaxation cycle. Here we show that two crystal structures for skeletal and cardiac calsequestrin are nearly superimposable not only for their subunits but also their front-to-front-type dimers. Ca2+ binding curves were measured using atomic absorption spectroscopy. This method enables highly accurate measurements even for Ca2+ bound to polymerized protein. The binding curves for both skeletal and cardiac calsequestrin were complex, with binding increases that correlated with protein dimerization, tetramerization, and oligomerization. The Ca2+ binding capacities of skeletal and cardiac calsequestrin are directly compared for the first time, with ∼80 Ca2+ ions bound per skeletal calse-questrin and ∼60 Ca2+ ions per cardiac calsequestrin, as compared with net charges for these molecules of ∼80 and ∼69, respectively. Deleting the negatively charged and disordered C-terminal 27 amino acids of cardiac calsequestrin results in a 50% reduction of its calcium binding capacity and a loss of Ca2+-dependent tetramer formation. Based on the crystal structures of rabbit skeletal muscle calsequestrin and canine cardiac calsequestrin, Ca2+ binding capacity data, and previous light-scattering data, a mechanism of Ca2+ binding coupled with polymerization is proposed.

UR - http://www.scopus.com/inward/record.url?scp=2342444645&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=2342444645&partnerID=8YFLogxK

U2 - 10.1074/jbc.M311553200

DO - 10.1074/jbc.M311553200

M3 - Article

VL - 279

SP - 18026

EP - 18033

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 17

ER -