Of all the model organisms to choose from, most might pit a unicellular alga as an underdog and perhaps hedge their bets on a more complex subject, like mice, or at least one with more than two functional extremities. But, if I were you, I would reconsider those wagers in favor of Chlamydomonas reinhardtii , a unicellular powerhouse that has swiftly joined the ranks as an indispensable research model. But what exactly is Chlamydomonas reinhardtii , and how has it supported basic research? Let's get acquainted with this curious creature! Chlamydomonas reinhardtii , otherwise referred to as C. reinhardtii or “Chlamy” is a no-frills model organism. This single-cell green alga is a humble ten micrometers in size and is composed of only a few cellular constituents, including a cell wall, a chloroplast, a pyrenoid, and an eyespot that senses light. Decorating its surface are two long, motile flagellar projections – like the tail a sperm uses to swim to an egg – that are of keen interest in research settings. Hi, i’m chlamydomonas reinhardti...but you can call me chlamy! 10 micrometers flagellum eye spot nucleus chloroplast pyrenoid Cilia are highly conserved throughout evolution, and Chlamy has proven to be a remarkable resource for studying ciliary regulation! Their cilia are widely used as models for basic science research; cilia-deficient mutants have helped researchers to identify evolutionarily conserved proteins involved in ciliary assembly, trafficking, and maintenance. Moreover, the simplicity and versatility of Chlamy further support its value as a scientific model – it is durable, low maintenance, rapidly propagated in controlled laboratory settings, and can survive in various temperature and light regimes. Perhaps unsurprisingly, Chlamy has quickly become a biological sensation! Several research sectors have adopted C. reinhardtii as their choice organism and have made triumphant strides in plant biology, evolutionary biology, and synthetic biology. Much has been gleaned from studying C. reinhardtii , yet there is still much to learn. Undeniably, studying the genetic similarities between human and algal flagella has been indispensable to our current understanding of ciliary growth, trafficking, and regulation. In recent years, however, researchers studying Chlamy's genetic differences added new wrinkles to what had been considered a well-characterized system. Thus, Chlamy’s value as a model organism lies in not just how it is similar to humans, but how it is not. By embracing and exploring the uniqueness of Chlamy – as well as the nearly limitless diversity of other “non-model organisms”, we can achieve a more holistic picture of the vastness of the natural world! Keepin’ up with Chlamy: A single cell with infinite value By: Kelly M. Montgomery These projections are called cilia, and are ubiquitous across eukaryotes, presenting on nearly all tissues and cell types. Cilia function by facilitating movement or transmitting signals from the environment to the interior of cells, much like an antenna receives and transduces a signal. These biological antennas are the first step in turning extracellular information (like the presence of nutrients) into decisions concerning tissue maintenance, cellular growth, and differentiation. As such, ciliary defects can have severe consequences for human health. cilia Decision making External stimuli Facilitates movement