Piubeli, Francine Amaral, Romero-Exposito, Francisco Javier, Olmedo, Maria, Merrow, Martha, Mata-Cabana, Alejandro, Geibel, Mirjam
[
International Worm Meeting,
2021]
During C. elegans postembryonic development, each of the four larval stages entails a process of feeding, a period of quiescence, and ecdysis. The repetitive nature of this process resembles oscillatory process as circadian rhythms. Nevertheless, each larval stage has a defined duration and entails specific events. A central question remains as to whether the overall speed of postembryonic development is controlled by a timer that affects all larval stages equally, as opposed to a linear process, where progression of development is achieved by the completion of stage specific events. The perturbation of a regulator of developmental timing would yield slower or faster animals, with larval stages that scale proportionally to the duration of total development. Contrarily, if development proceeds in a linear manner, based on completing stage-specific events, perturbations that affect overall duration of development might have different impact on different stages, depending on the specific events that take place during each stage. The answer to this question calls for precise quantification of postembryonic development in response to varied perturbations that alter overall developmental timing. We have measured the duration of each stage of larval development for over 2,500 larvae, upon perturbations in temperature, in food quantity and quality, and amount of insulin signaling. Importantly, the assay we used monitors development continuously, with a time resolution of five minutes, and resolves the transitions between molts and intermolts. We observed that interventions that alter developmental timing have a differential effect on the discrete stages of larval development. Furthermore, our high-resolution measurement of the effect of temperature has unveiled characteristic features of temperature dependence in C. elegans postembryonic development. Altogether, our results support a mechanism based on a linear progression of postembryonic development, where the events that take place in each stage are differentially impacted by environmental perturbations.