Table 1.

Types of treatment performed to study specifically chaetogenesis and neurogenesis processes. Four time windows were chosen. Time window 1 encompasses both processes and gives a general view of the potential functions of the Notch pathway in the annelid Platynereis. Time window 2 allows targeting the cell fates of chaetal sacs. Time window 3 encompasses the larval neuron formation. Time window 4 encompasses ‘adult’ neurogenesis. For each time window and drug concentration, the phenotype and results observed at several stages are mentioned. VNC, ventral nerve cord; conc., concentration.

drug conc.	Time window 1: 24–48 hpf		Time window 2: 20–48 hpf		Time window 3: 12/16–24 hpf		Time window 4: 30–48 hpf
	stages	phenotypes	stages	phenotypes	stages	phenotypes	stages	phenotypes
LY-411575 1 µM	48 hpf	follicle cells markers expression decreased; neurogenesis markers expression maintained	48 hpf	overexpression of chaetoblast marker; presence of abortive chaetoblasts	24 hpf	Elav expression in maintained in 9 neurons	72 hpf	normal number of brain cells/ number of VNC neurons slightly enhanced
	72 hpf	absence of chaetae/normal chaetoblasts; normal VNC	72 hpf	absence of chaetae; development slightly delayed	72 hpf	absence of chaetae
	6 dpf	absence of chaetae/normal VNC
RO-4929097 2 µM	48 hpf	follicle cells markers expression decreased; neurogenesis markers expression maintained	48 hpf	absence of chaetae/very few abortive chaetoblasts
	72 hpf	absence of chaetae/normal chaetoblasts; normal VNC	72 hpf	absence of chaetae
	6 dpf	absence of chaetae/normal VNC
RO-4929097 30 µM	48 hpf	absence of chaetae/development delayed	48 hpf	abnormal expression of chaetoblast marker; presence of abortive supernumerary chaetoblasts	24 hpf	Elav expression is maintained in 9 neurons	72 hpf	normal number of brain cells; development delayed
	72 hpf	absence of chaetae/development delayed	72 hpf	absence of chaetae; development delayed	72 hpf	absence of chaetae; development delayed
	later	dead
DAPT 40 µM	48 hpf	follicle cells markers expression decreased; neurogenesis markers expression maintained
	72 hpf	absence of chaetae/normal chaetoblasts; normal VNC
	6 dpf	absence of chaetae/normal VNC