Related Experiment Video
Updated: Jul 5, 2026
10:56
Analysis of Cardiomyocyte Development using Immunofluorescence in Embryonic Mouse Heart
Published on: March 26, 2015
Cardiac myofibrillogenesis inside intact embryonic hearts
Aiping Du1, Jean M Sanger, Joseph W Sanger
1Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6058, USA.
Developmental Biology
|May 6, 2008
Summary
This study reveals that muscle cells form myofibrils in three distinct stages, both in developing hearts and in cell cultures. Researchers also found initial myosin filaments are shorter, suggesting titin
Area of Science:
- Muscle biology
- Cellular development
- Cardiovascular research
Background:
- The precise mechanism of myofibril assembly in cardiomyocytes remains debated.
- Previous studies proposed a three-stage model based on cultured cells, but in situ evidence was lacking.
- Discrepancies existed between myofibrillogenesis in cultured versus uncultured cardiomyocytes.
Purpose of the Study:
- To investigate in situ myofibrillogenesis in early avian heart development.
- To determine if the proposed three-stage model applies to cardiomyocytes within the developing heart.
- To explore the role of titin in myosin filament length determination during early myofibril formation.
Main Methods:
- Utilized non-enzymatic procedures for sample preparation.
- Employed deconvolution imaging techniques for high-resolution visualization.
- Examined in situ early heart-forming regions in avian embryos (2- to 13-somite stages).
Main Results:
- Successfully detected the three proposed stages of myofibril assembly (premyofibrils, nascent myofibrils, mature myofibrils) in situ.
- Confirmed that myofibrillogenesis follows the same three-step process in cardiomyocytes, regardless of whether they are in situ, in organ culture, or tissue culture.
- Observed that initial myosin filaments are approximately half the length of mature filaments before titin organization, suggesting titin's role in length regulation.
Conclusions:
- The three-stage model of myofibrillogenesis is valid for cardiomyocytes in situ, supporting its general applicability.
- Titin likely plays a crucial role in determining the final length of myosin filaments during sarcomere assembly.
- This research clarifies a fundamental process in cardiac muscle development and protein organization.
Related Concept Videos
01:13Formation of Muscle Fibers from Myoblasts
De novo myogenesis, or the formation of muscle fibers, begins during the early embryonic stages. The skeletal muscle is formed from somites– blocks of embryonic cell layers. The somites are further divided into dermatomes, myotomes, sclerotomes, and syndetomes. Among these, the myotomes give rise to muscle fibers.
Muscle progenitor cells (MPCs) are formed from the myotomes. MPCs express genes that encode the transcription factors Pax3 and Pax7. Along with Pax 3/7, other transcription factors...
Muscle progenitor cells (MPCs) are formed from the myotomes. MPCs express genes that encode the transcription factors Pax3 and Pax7. Along with Pax 3/7, other transcription factors...
01:27Development of the Heart
The development of the human heart, a crucial organ, commences from the mesoderm on the 18th or 19th day after fertilization. This process initiates in the cardiogenic area, a group of mesodermal cells at the embryo's head end, which evolves into elongated strands known as cardiogenic cords. These cords undergo a transformation to form hollow-centered endocardial tubes.
As the embryo undergoes lateral folding, these paired tubes approach each other, merging into a single primitive heart tube by...
As the embryo undergoes lateral folding, these paired tubes approach each other, merging into a single primitive heart tube by...
01:13Structure of Cardiac Muscles
Cardiac muscle, or myocardium, is a specialized type of muscle found exclusively in the heart. Its unique structural and functional characteristics enable the heart to perform its vital role of pumping blood throughout the body continuously and rhythmically. The cardiac muscle cells, or cardiomyocytes, possess an endomysium and perimysium but do not have an epimysium.
Compared to skeletal muscles, cardiac muscle cells are small and mostly have a single nucleus. Additionally, they are usually...
Compared to skeletal muscles, cardiac muscle cells are small and mostly have a single nucleus. Additionally, they are usually...
01:27Specialized Characteristics of Cardiac Muscles
The primary role of cardiac muscles is to propel blood throughout the cardiovascular system. The cardiac muscle cells, or cardiomyocytes, exhibit specialized characteristics that allow them to perform this function.
Cardiac muscle cells are smaller than skeletal muscles, averaging 10–20 mm in diameter and 50–100 mm in length. However, they have large energy demands for continuous contraction and relaxation. This energy is almost exclusively derived from aerobic metabolism of energy reserves in...
Cardiac muscle cells are smaller than skeletal muscles, averaging 10–20 mm in diameter and 50–100 mm in length. However, they have large energy demands for continuous contraction and relaxation. This energy is almost exclusively derived from aerobic metabolism of energy reserves in...