Muscle cells point the finger at each other

Nov 22, 2010

A new study reveals that muscle cells fuse together during development by poking "fingers" into each other to help break down the membranes separating them. The study appears online on November 22, 2010 in the Journal of Cell Biology.

During muscle development, individual fuse together to form long myotubes containing multiple cell nuclei. In the fruit fly Drosophila melanogaster, fusion occurs between two different types of muscle cell: founder cells and fusion-competent myoblasts. Using to analyze developing fly embryos, Elizabeth Chen and colleagues from the Johns Hopkins University School of Medicine in Baltimore, MD, discovered that fusion-competent myoblasts send multiple "finger-like" protrusions into neighboring founder cells. These fingers contained large amounts of the cytoskeletal protein actin, and their formation required several proteins that stimulate the assembly of actin molecules into long filaments.

The actin-rich fingers helped form a small pore connecting the founder cell and fusion-competent myoblast, which gradually expands to fuse the two cell types together. The researchers think that the fingers assist pore formation by pushing the two cell membranes extremely close to each other.

The structure and behavior of these myoblast fingers are very similar to other types of actin-rich protrusions called invadosomes that researchers have previously identified in and other cell types in culture. But this is the first example of this type of structure in a developing tissue. The researchers now want to investigate how these invasive myoblast fingers are formed and controlled.

Explore further: Scientists unlock secrets of protein produced by disease-causing fungus

More information: Sens, K.L., et al. 2010. J. Cell Biol. doi:10.1083/jcb.201006006

add to favorites email to friend print save as pdf

Related Stories

Researchers Find 'Fusion' Protein

Apr 11, 2007

Working with fruit flies, scientists at Johns Hopkins have discovered a protein required for two neighboring cells to fuse and become one "super cell."

Researchers Uncover Cell Fusion Mechanism

Oct 08, 2006

In a study that could shed light on disorders that occur in skeletal muscles, bone, the placenta, and other organs where fused cells are common, researchers at the Technion-Israel Institute of Technology and at the US National ...

How actin networks are actin'

Jan 02, 2008

Dynamic networks of growing actin filaments are critical for many cellular processes, including cell migration, intracellular transport, and the recovery of proteins from the cell surface. In this week’s issue of the open-access ...

Researchers develop mouse model for muscle disease

Sep 05, 2006

Researchers from the University of Minnesota have identified the importance of a gene critical to normal muscle function, resulting in a new mouse model for a poorly understood muscle disease in humans.

Understanding the migration of cancer cells

Jun 23, 2008

[B]Activity of regulatory proteins for the growth of filopodia and lamelopodia clarified[/B] Lamellipodia are veil-shaped protrusions of the plasma membrane, that can turn into upward-curled ruffles if they fail to adhere to ...

Recommended for you

For cells, internal stress leads to unique shapes

8 hours ago

From far away, the top of a leaf looks like one seamless surface; however, up close, that smooth exterior is actually made up of a patchwork of cells in a variety of shapes and sizes. Interested in how these ...

Adventurous bacteria

9 hours ago

To reproduce or to conquer the world? Surprisingly, bacteria also face this problem. Theoretical biophysicists at Ludwig-Maximilians-Universitaet (LMU) in Munich have now shown how these organisms should ...

Revealing camouflaged bacteria

11 hours ago

A research team at the Biozentrum of the University of Basel has discovered an protein family that plays a central role in the fight against the bacterial pathogen Salmonella within the cells. The so cal ...

User comments : 0

More news stories

Revealing camouflaged bacteria

A research team at the Biozentrum of the University of Basel has discovered an protein family that plays a central role in the fight against the bacterial pathogen Salmonella within the cells. The so cal ...

Chimpanzees prefer firm, stable beds

Chimpanzees may select a certain type of wood, Ugandan Ironwood, over other options for its firm, stable, and resilient properties to make their bed, according to a study published April 16, 2014 in the open-access ...