We recently conducted a study that aimed to describe the differentiation mechanisms used to generate O2 and CO2 sensing neurons in C. elegans. We identified
egl-13/Sox5 to be required for the differentiation of both O2 and CO2 sensing neurons. We found that
egl-13 functions cell autonomously to drive O2 and CO2 sensing neuron fate and is therefore essential for O2 and CO2 sensing-induced behaviors. Through systematic dissection of the
egl-13 promoter we identified upstream regulators of
egl-13 and proposed a model of how differentiation of O2 and CO2 sensing neurons is regulated. In this commentary we discuss our findings and open questions we wish to address in future studies.