Table 1.

Summary of domain structures and expression evidence for LIM homeobox genes found in four early animal genomes

Subfamily	Nematostella		Hydra		Trichoplax		Amphimedon
	Domains	Expressed	Domains	Expressed	Domains	Expressed	Domains	Expressed
Apterous (Lhx2/9)	L-L-H	Y	L-L-H	Y	L-L-H	Y	-	-
Arrowhead (Lhx6/8)	L-L-H	Y	L-H	Y	L-L	Y	-	-
Islet	L-L-H	Y	-	-	L-L-H	-	L-L-H	Y
lin-11 (Lhx1/5)	L-L-H	Y	L-L-H	Y	L-L-H	Y	L-L-H	Y
Lhx3/4	L-L-H	N	-	-	L-L-H	-	L-L-H	Y
Lmx	L-H	Y	L-L-H	Y	L-L-H	-	-	-

H = homeodomain; L = LIM domain; N = not found to be expressed by reverse transcription polymerase chain reaction (RT-PCR); Y = expressed.