Cytokinesis Lab

Dr. Katie Shannon's Cytokinesis Lab at Missouri S&T

Su Young Park and Jung Eun Park, former Master's students

Amy Hunt, former undergraduate in the lab

Katie Stockstill, current Master's student

My major research interest is the assembly and contraction of the actomyosin ring in budding yeast. Other interests are microscopy, synthetic biology and iGEM, and cellular uptake and transport of nanoparticles.

Contact and Biographical information for Dr. Shannon user:Katie_B_Shannon

Assembly and Contraction of the Actomyosin Ring in Budding Yeast

What is the actomyosin ring?

    The actomyosin ring is a structure composed of actin filaments, type II myosin, and other proteins.  Myosin is a molecular motor that “walks” along actin filaments.  
    Myosin movement along actin filaments causes a contraction or constriction of the ring.  As the actomyosin ring contracts, it pulls the plasma membrane of the cell.  
    This process is called cytokinesis, which is the physical division of one cell into two.
    Click here to see a movie of myosin-GFP contraction in a living yeast cell.

Why study budding yeast?

    Budding yeast, Saccharomyces cerevisiae, are also commonly known as baker's or brewer's yeast.  These yeast cells are eukaryotic, 
    and many genes are conserved between yeast and human cells.  Both yeast and human cells utilize a contractile ring made of actin filaments 
    and type II myosin (the actomyosin ring) in order to divide.  We hope that by studying the complex process of cytokinesis in the simpler yeast cells, 
    we will learn fundamental concepts that will be applicable to  cytokinesis in other cells.

Why is regulation of actomyosin ring assembly and contraction important?

    When a cell divides, it is important that each cell receives the correct number of chromosomes and therefore the complete genetic blueprint.  
    Cancer cells almost always have an abnormal number of chromosomes.  Recent studies have shown that an early step in tumor formation may be cytokinesis failure, 
    which leads to tetraploidy (four copies of each chromosome).  Cytokinesis must be coordinated with chromosome segregation (mitosis) to ensure that each cell 
    receives the right number of chromosomes.  Determining how cytokinesis is normally regulated will help us to understand how this process can fail and contribute to tumor progression. 

What are our current lab projects?