Table 1. Presence of RNAi proteins in S. pistillata in comparison to Cnidaria and other model organisms (‘+’: presence, ‘−’: absence, ‘?’: not determined).

	Organism	Ago	Piwi	Dicer	Drosha	Pasha	HEN1
Cnidaria	S. pistillata	+	+	+	+	+	+
	N. vectensis	+	+	+	+	+	+
	A. millepora	+	?	+	+	+	+
	A. digitifera	+	?	+	+	+	−
	H. vulgaris	+	?	+	+	+	+
	H. magnipapillata	+	+	+	+	?	?
Other	H. sapiens	+	+	+	+	+	+
	D. melanogaster	+	+	+	+	+	+
	C. elegans	+	+	+	+	+	+
	A. thaliana	+	−	+	−	−	+
	S. pombe	+	−	+	−	−	−