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From 2012.igem.org

Eukaryotic Cell

"Eukaryopedia" in progress

In the world of synthetic biology and specifically in the iGEM competition, most of the teams work on prokaryotic cells. However some of them tried to "legitimate" the use of Eukaryote as another model. Our project fully supports this mindset introduced with Eukaryopedia by Heidelberg Team in 2009.

Introduction to Eukaryote

The term eukaryote means the entire living organisms on our planet whose cells contain complex structures enclosed within membranes. Eukaryotic cell is part of the three reigns of living systems including Bacteria and Archaea, both prokaryotes. Nucleus, within which the genetic material is carried, is the membrane-bound structure that set eukaryotes apart from prokaryotes. Indeed Prokaryote includes many unicellular organisms whose cells lack a cell nucleus or any other membrane-bound organelles.

Differences between a typical eukaryotic cell and a bacterium

Eukaryotic cells are known to be much larger than those of prokaryotes, on average 50µm and 1µm respectively. They have a variety of internal membranes and structures, called organelles, and a cytoskeleton composed of microtubules, microfilaments, and intermediate filaments, which play an important role in defining the cell's organization and shape. This difference of complexity between eukaryotes and prokaryotes justifies why bacteria are preferentially used in system and synthetic biology. It’s easier, for example, to express proteins and detect them in a single structure such as a bacterium compared to a multicellular system.
Eukaryote represents then a large complex organism including animals, plants and fungi. Most of them contain other membrane-bound organelles such as mitochondria, chloroplasts and the Golgi apparatus.

Endomembrane system

The endomembrane system is composed of different compartments suspended in the cytoplasm. They are important in protein expression and their addressing to different cellular structures. These compartments or organelles include the cell membrane, the endoplasmic reticulum (rough or smooth according to the tissue), the Golgi apparatus, lysosomes, vacuoles, vesicles, peroxisomes and endosomes.