Domain	Number of genes
UAA	27
UAE_UbL	6
uaf-1	1
uaf-2	1
UBA	57
uba-1	1
uba-2	1
UBA_4	41
uba-5	1
UBA_5	3
UBA_6	4
UBACT	13
UBA_e1_C	5
UBA_e1_thiolCys	20
ubc-1	1
ubc-12	1
ubc-13	1
ubc-14	1
ubc-15	1
ubc-16	1