Flagellar length control in biflagellate eukaryotes : Cooperative phenomena of generating and regenerating the flagellum

Chlamydomonas Reinhardtii is a biflagellate eukaryote which generates its own flagella of correct length (in a controlled manner) after cell division (ciliogenesis), regenerates both of them after deflagellation and regenerates the amputated flagellum. A pool of proteins needed to form, maintain and regenerate the flagella is synthesized in the cell body. These proteins are transported from the pool to the distal tips for flagellar assembly and those released from the flagellar tip due to ongoing turnover are shuttled back to the pool by intraflagellar transport trains. Combining the dynamics of trafficking intraflagellar transport trains, the pool and the kinetics of flagellar assembly and disassembly, we have developed a stochastic model for understanding the collective phenomena of flagellar length control. Our model accounts for all key features of experimentally known phenomena which include ciliogenesis, resorption, deflagellation as well as regeneration after selective amputation of one of the two flagella. Moreover, we show how the communication among both the flagella through the common pool influences the nature, duration and extent of regeneration under different circumstances and governs the correlations between the fluctuating lengths of the two flagella.