The Amoeba Chronicles part 1: Slime That Farms?

(image from M.J. Grimson & R.L. Blanton)

So it's been some time since we last posted... during that time the Minions of Science been combing the tenuous edges of the www to bring you even more tantalizing goodies. This post is more or less a lead-in to a recent paper I came across about everyone's favorite amoeba (developmental/molecular biologists that is), Dictyosteliuma discoideum or commonly referred as slime mold! Lets just call them Dicty for short. So, lets wet your knowledge palate

Dicty is a common model organism used in developmental and molecular biology to study cell communication, differentiation (process in development in which cells become a more specialized cell type, such as an stem cell becoming a neuron) and programmed cell death (apotosis) to name a few. Researchers also find Dicty bizarre in that it's a social amoeba. During it's life cycle it feeds on bacteria as a collection of single celled organisms that will cooperate and aggregate together as a multicelluar "slug" (during times of stress), becoming a fruiting body with various specialized cells that shoot out spores... starting its odd life anew.

Hold the phone, a single celled protist forming a multicellular conglomerate of specialized cells? Was my reaction as I sat in Developmental Bio years ago. Probably not your initial reaction, but you get the message. However, this little eukaryote continues to become more and more interesting. A recent paper in Nature showed that Dicty is in fact a primitive farmer (or the MOST primitive one at that)! This suggests that the agriculture evolved alot earlier than that of our human ancestors or other animals. The paper shows that when Dicty transitions into the fruiting body stage some of the cells actually carry with them a sample of bacteria, which is used to inoculate a new area where the spore lands allowing it to grow and feed the cycle all over. The strangeness of life... I LOVE IT.



So there you go, farming amoebas. Next post in the series will build on the complexities of Dicty from another pretty cool Science paper that shows Dicty cells forming a polarized epithelium that hails back to our metazoan origins. Meaning that the evolution of multicelluarity (and some components of the wnt-signaling pathway, Don't worry I'll explain all of this later) could be more ancient than previously thought.

This concludes your daily dose of knowledge... until next time, read on Loyal Readers!