Table 2.

Transcription Factors Involved in the Tube Formation of Vestimentiferans (vest) and Hard Structures in Other Lophotrochozoans for Which Data are Available.

Transcription Factora	Annelida		Mollusca			Brachiopoda
	Tube (vest)	Chaetae	Shell	Scale	Radula	Spicules	Shell	Chaetae
Arx		+	+		+			+
Hox1/Lab		+	+					+
Post1		+	+					+
En			+			+	+
Hox5/Scr			+				+
Hox4/Did			+				+
Antp				+			+
Zic	+	+		+				+
Evx		+		+
Mox		+		+
Hox2/Pb		+		+
Brachyury			+		+
ETS			+
Dlx			+
Goosecoid			+
Msx			+
Six3/6			+
Gbx	+			+	+	+
Soxb2/Sox14				+
Grainyhead				+
Hox3				+
Lox4	+			+
Lox5	+			+
Pax3/7				+
Pax6				+	+
Hes1		+			+			+

^aTranscription factors included those from Hilgers et al. (2018) and Sun et al. (2020).