Table 2. Validation of transcription factor expression in brachial MNs.

TF	Type	Novel TF with MN expression	e12 MNs	p8 MNs	p56 MNsISH Allen Brain	p60snRNA-Seq dataset	Expression in other spinal cells at e12
Ebf2	Ebf/COE	No	+	–	–	–	+
Islet1	LIM HD	No	+	+	+	N.D	+
Islet2	LIM HD	No	+	+	+	N.D	+
Hb9	HD	No	+	+	+	N.D	+
Foxp1	FOX	No	+	+	–	+	–
Lhx3	LIM HD	No	+	+	N.D	–	+
Runx1	RUNX	No	+	+	+	–	–
Hoxc4	HOX	No	+	+	+	+	+
Hoxa5	HOX	No	+	+	N.D	–	+
Hoxc5	HOX	No	+	+	+	+	+
Hoxa6	HOX	No	+	+	–	–	+
Hoxc6	HOX	No	+	+	N.D	–	+
Hoxa7	HOX	No	+	+	+	–	+
Hoxc8	HOX	No	+	+	N.D	–	+
Irx1	IRO HD	Yes	+	+	+	–	+
Irx2	IRO HD	Yes	+	+	+	–	+
Irx3	IRO HD	Yes	+	+	+	–	–
Irx5	IRO HD	Yes	+	+	+	–	–
Irx6	IRO HD	Yes	+	+	+	–	–
Creb5	CRE	Yes	+	+	+	+	–
Esrrg	NHR	Yes	+	+	–	+	+
Fos	FOS	Yes	+	+	+	–	+
Arid5a	ARID	Yes	+	+	–	–	+
Irf1	IRF	Yes	+	+	–	–	+
Irf8	IRF	Yes	+	+	–	–	+
Klf6	KLF	Yes	+	+	–	+	–
Tshz1	C2H2 Zn	Yes	+	+	+	+	+
Zfp296	ZFP	Yes	+	+	+	–	+
Neurod6	bHLH	N.A	–	–	N.D	–	Dorsal interneurons
Arid5b	ARID	N.A	–	–	N.D	+	Dorsal interneurons
Pou3f3	POU	N.A	–	–	N.D	+	Dorsal interneurons
Mafb	bZIP	N.A	–	–	N.D	N.D	Ventral interneurons
Zfhx4	Zn HD	N.A	–	–	N.D	+	Ventral interneurons
Elk3	ETS	N.A	–	–	N.D	+	Vasculature
Epas1	HIF	N.A	–	–	N.D	–	Vasculature
Heyl	bHLH	N.A	–	–	N.D	–	Vasculature

Expression in p60 brachial MNs was determined using the Allen Brain Map (http://portal.brain-map.org). We also interrogated the single nucleus (sn) RNA-seq datasets of p60 spinal MNs from http://spinalcordatlas.org/. + denotes expression; – denotes no expression; N. D: Not determined; N. A: Not applicable.

RNA-Seq: RNA-sequencing.