Evidence map›Paper›PMID 42647613›Full record

ArticleScience advances2026

The structure of the native cardiac crossbridge in the rigor state.

Cristina M Risi, Tyler Nguyen, Betty Belknap, Howard D White, Jose R Pinto, Prescott B Chase, Vitold E Galkin

Abstract read
In one paragraph

Article in Science advances, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

7 authors.

Cristina M RisiDepartment of Biomedical and Translational Sciences, Macon & Joan Brock Virginia Health Sciences at Old Dominion University, Norfolk, VA 23507, USA.ORCID 0000-0002-3145-2072
Tyler NguyenDepartment of Biomedical and Translational Sciences, Macon & Joan Brock Virginia Health Sciences at Old Dominion University, Norfolk, VA 23507, USA.
Betty BelknapDepartment of Biomedical and Translational Sciences, Macon & Joan Brock Virginia Health Sciences at Old Dominion University, Norfolk, VA 23507, USA.ORCID 0000-0002-0935-0336
Howard D WhiteDepartment of Biomedical and Translational Sciences, Macon & Joan Brock Virginia Health Sciences at Old Dominion University, Norfolk, VA 23507, USA.
Jose R PintoDepartment of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, USA.ORCID 0000-0001-9092-4976
Prescott B ChaseDepartment of Biological Science, Florida State University, Tallahassee, FL, USA.ORCID 0000-0001-9701-561X
Vitold E GalkinDepartment of Biomedical and Translational Sciences, Macon & Joan Brock Virginia Health Sciences at Old Dominion University, Norfolk, VA 23507, USA.ORCID 0000-0003-1138-7565

Funding

REGULATION OF THE ACTIN FILAMENT POINTED END DYNAMICS IN HEALTH AND DISEASER01GM120137 · NIGMS · WASHINGTON STATE UNIVERSITY · PI GALKIN, VITOLD, GREGORIO, CAROL C · 2017 to 2024
$4.0M
The mechanisms of cardiac thin filament regulation in health and disease.R01HL160966 · NHLBI · OLD DOMINION UNIVERSITY · PI CHASE, P. BRYANT, GALKIN, VITOLD · 2022 to 2025
$2.3M
Mechanisms Of Thin Filament Regulation by Cardiac Myosin-Binding Protein C In Health and DiseaseR01HL181965 · NHLBI · OLD DOMINION UNIVERSITY · PI Brett A Colson, Vitold Galkin · 2026 to 2026
$1.6M
NHLBI NIH HHS R01 HL160966NHLBI NIH HHS R01 HL181965NIGMS NIH HHS R01 GM120137
6 · The paper itself

Abstract

Cardiac contraction is driven by double-headed myosin cycling on cardiac thin filaments, where troponin-tropomyosin regulates myosin access to actin. Prior high-resolution structural studies used a single-headed myosin bound to bare actin, thereby limiting insight into coordination between myosin heads and the influence of troponin-tropomyosin on actomyosin interactions. Here, we report a high-resolution structure of the native cardiac rigor cross-bridge formed by heavy meromyosin bound to the thin filament. We show that direct communication between the two bound heads, uneven interactions between the heads and tropomyosin, and spatial constraints imposed by troponin govern myosin placement along the thin filament. Additionally, the two heads display non-equivalent motor-light chain interactions, yielding distinct lever-arm conformations indicative of asymmetric intramolecular strain. Together, these findings provide a structural framework for how the two myosin heads coordinate and how the components of the thin filament are integrated into force generation by active cross-bridges.

Indexed as

MyocardiumActin CytoskeletonActinsActomyosinAnimalsModels, MolecularMyocardial ContractionMyosinsProtein BindingProtein ConformationTropomyosinTroponinActinsActomyosinMyosinsTropomyosinTroponin

Identifiers

PMID42647613
PMCPMC13510625

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.