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Cooperation and conflict in the life cycle 
Picture courtesy:Sathiyanarayanan Manivannan, Graduate student, OSU. What are cellular slime molds? Cellular slime molds are soil-dwelling microorganisms alternating their life cycle between unicellular growth and multicellular development. As unicellular amoeboid cells, they feed on bacteria and proliferate. However, on starvation, hundreds to thousands of amoebae signal each other, aggregate by chemotaxis and forms a bullet shaped 'slug'. Cells at the slug anterior differentiate to a dead stalk while the rest of the cells encapsulate as spores in a fruiting body. In favorable circumstances, the spores disperse establishing a new territory. As the identity of the cell is retained throughout the life cycle, they are called ‘cellular’ slime molds. As a group cellular slime molds are also called as Dictyostelids or Social amoebae as they come together at times of crisis with a marked division of labor in the group of cells. Among slime molds, Dictyostelium discoideum is widely used as model organism. For more details, visit www.dictybase.org |
Why Dictyostelium discoideum as a model system? Only in the complete absence of growth or cell division, multi-cellular development begins in all slime molds including Dictyostelium, thus allowing one to track each process independent of the other. Just two cell differentiated cell types make up this organism; a dead stalk and dormant spores. Various molecular tools are established in Dictyostelium and with an array of mutants impaired in different developmental processes it is possible to study many fundamental problems in biology. Also, there is an earnest attempt to sequence the genome of different slime mold species and this will pave way for exciting research ahead. For a detailed description of cellular slime molds, please go to www.dictybase.org |