Constitutive active and inactive mutant forms of Arl1p did not complement the loss of Arl1p. GFP-IMH1pRS314 was transformed into arl1-deleted cells containing integrated wild-type, constitutively active (Q72L), constitutively inactive (T32N), Arl1p, or empty vector control (YIplac128). After induction with 2% galactose and 0.1% glucose medium, live cells were observed with microscopy.