Related Experiment Video

Updated: Jul 9, 2026

En Face Endocardial Cushion Preparation for Planar Morphogenesis Analysis in Mouse Embryos
08:57

En Face Endocardial Cushion Preparation for Planar Morphogenesis Analysis in Mouse Embryos

Published on: July 27, 2022

Myocardin expression during avian embryonic heart development requires the endoderm but is independent of BMP

Andrew S Warkman1, Tatiana A Yatskievych, Katharine M Hardy

  • 1Department of Cell Biology and Anatomy, University of Arizona, Tucson, Arizona, USA.

Developmental Dynamics : an Official Publication of the American Association of Anatomists
|December 12, 2007
PubMed

Insights

Myocardin, a key regulator of heart development, is expressed early in chicken embryos. Its expression in the precardiac mesoderm is independent of bone morphogenetic protein (BMP) signaling and Nkx2.5.

Area of Science:

  • Developmental Biology
  • Molecular Cardiology
  • Transcriptional Regulation

Background:

  • Myocardin is a critical cofactor for serum response factor, essential for heart and smooth muscle development.
  • Understanding the precise role of myocardin during early cardiac development is crucial for elucidating heart formation mechanisms.

Purpose of the Study:

  • To investigate the function and expression pattern of myocardin during the early stages of heart development in chicken embryos.
  • To determine the regulatory pathways controlling myocardin expression in the developing heart.

Main Methods:

  • Isolation and characterization of the chicken orthologue of myocardin.
  • Expression analysis using Hamburger and Hamilton stages (3-15) of chicken embryonic development.
  • Embryonic dissection studies to identify signaling requirements for myocardin expression.

Main Results:

  • Myocardin transcripts were detected in lateral/extraembryonic mesoderm, precardiac mesoderm, myocardium, and vascular smooth muscle cells.
  • Myocardin expression precedes that of Nkx2.5 in the developing chicken embryo.
  • Endodermal signals are required for myocardin expression in the precardiac mesoderm, independent of BMP signaling.

Conclusions:

  • Early myocardin expression in the precardiac mesoderm is regulated by endoderm-derived signals.
  • Myocardin expression is initiated through a signaling pathway parallel to and independent of Nkx2.5.
  • These findings reveal a novel regulatory mechanism for early cardiac gene expression.

More Related Videos

Microinjection-based System for In Vivo Implantation of Embryonic Cardiomyocytes in the Avian Embryo08:52

Microinjection-based System for In Vivo Implantation of Embryonic Cardiomyocytes in the Avian Embryo

Published on: February 17, 2019

Isolation and Culture of Avian Embryonic Valvular Progenitor Cells14:02

Isolation and Culture of Avian Embryonic Valvular Progenitor Cells

Published on: October 27, 2010

Related Concept Videos

Determination01:51

Determination

During embryogenesis, cells become progressively committed to different fates through a two-step process: specification followed by determination. Specification is demonstrated by removing a segment of an early embryo, “neutrally” culturing the tissue in vitro—for example, in a petri dish with simple medium—and then observing the derivatives. If the cultured region gives rise to cell types that it would normally generate in the embryo, this means that it is specified. In contrast, determination...
Development of the Heart01:27

Development 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...
Gastrulation01:56

Gastrulation

Gastrulation establishes the three primary tissues of an embryo: the ectoderm, mesoderm, and endoderm. This developmental process relies on a series of intricate cellular movements, which in humans transforms a flat, “bilaminar disc” composed of two cell sheets into a three-tiered structure. In the resulting embryo, the endoderm serves as the bottom layer, and stacked directly above it is the intermediate mesoderm, and then the uppermost ectoderm. Respectively, these tissue strata will form...
Role Of Notch Signalling In Intestinal Stem Cell Renewal01:12

Role Of Notch Signalling In Intestinal Stem Cell Renewal

Notch signaling was first discovered in Drosophila melanogaster, where it is involved in cell lineage differentiation. Notch signaling regulates the maintenance and differentiation of intestinal stem cells or ISCs by controlling the expression of atonal homolog 1 or Atoh1. Atoh1 directs cells to differentiate into secretory cells.
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...