Table 1.

Molecular players in key steps of GABAergic neurogenesis

Function
Brain region	Spatial patterning and progenitor specification HD or bHLH proteins	Proneural genes and their regulators bHLH proteins	Postmitotic subtype selection HD, bHLH, ZF	Maturation, migration, maintenance HLH, HD, ZF
Telencephalon	MGE: NKX2-1 [42]	ASCL1 [85, 86, 196]	DLX2 [113–115]	ARX [115, 178, 179]
			DLX5/6 [106, 119]	DLX5/6 [119, 192]
	LGE, CGE: GSX1/2 [48, 50, 77]
				NR2F2 [182]
				LHX6 [185]
	POA: NKX5-1 [45]
	POA: DBX1 [44]
	DLX1/2 [106, 108]
Diencephalon	NKX2-2 [59, 89]	ASCL1 [91]	p3: DLX2 [93]	p1-2: SOX14 [93]
				aTAL1 [19, 59]
	FEZF1/2 [58]	p1-2: HELT [91, 93]	p1-2: GATA2 [19]
			p1-2: aTAL2
				aGATA3 [199]
	GBX2 [197]
	PAX6 [198]
Midbrain	NKX2-2	ASCL1 [88, 91]	GATA2 [21, 121]	PITX2 [203]
	NKX6-1
	PAX3/7 [200–202]
		HELT [22, 90]	TAL2 [121]	aGATA3 [60, 199]
				aTAL1 [21, 121]
				aLHX1/5 [21, 22]
Ventral R1	NKX6-1 [26, 204]	ASCL1 [91]	TAL1 [60]	TAL1 [60]
		aNGN1/2		PITX2 [205]
Dorsal R1 (cerebellum)	EN2 [206–208]	ASCL1 [95, 97, 210]	PTF1A [125, 126]	LHX1/5 [144]
				NGN1/2 [99]
		NGN1/2 [25, 99]
				aCORL, PAX2 [124, 211]
	PTF1A [125, 209]
Dorsal spinal cord	dP4: GSX1/2 [94]	ASCL1 [94, 96]	dI4, dIL, dI6: LBX1 [72, 76, 104]	LBX1 [72, 76, 104]
				LHX1/5 [143]
			dI4, dIL: PTF1A [102]
		NGN1/2 [212]
	dP6: DBX2 [69, 73]
	PAX2 [128]
Ventral spinal cord	NKX6-1 [36, 69]	ASCL1 [66]	V2b: TAL1 [101]	V2b: TAL1 [63, 103]
	V0-1: DBX1/2 [36, 69, 72]
		aNGN1/2
		V2: FOXN4 [66, 67]
			GATA2 [64, 103]
			LMO4 [123]
			V0d: aEVX1- [213]
				GATA3 [62, 63]
				LMO4 [123]
				V1: EN1 [71]
Mutant phenotype (mouse)	GABAergic progenitors mispatterned or missing	GABAergic neurogenesis delayed and/or diminished	GABAergic precursors respecified to alternative fate	Incomplete differentiation/impaired functionality

^aMarked genes are expressed in GABAergic neurons but their role in fate specification or mechanism of action is unclear