Figure 1.
(A) Complementing activity of clones containing the SEC34 gene. Only the cloned insert is shown. B/S, BamHI-Sau3A junction; P, PvuII; Bs, BstEII; SI, SacI; S, SalI; Bg, BglII; Sp, SphI; Af, AflII; SII, SacII; A, AgeI. (B) The N-terminal coiled-coil region of Sec34p is important for its function. Sec34p has a high probability of forming a coiled-coil region between amino acids 87 and 114. Plasmids pDK301 and pDK401 contain the entire SEC34 gene, whereas pDK307 and pDK407 harbor the extreme N terminus of Sec34p (amino acids 1–85) lacking the coiled-coil domain. This domain is present in pDK306 and pKD406 (which contain amino acids 1–128). The sec34-1 and sec34-2 mutants were transformed with these constructs and incubated for 2 d at 37°C to test for suppression. All constructs, except for pDK307 and pDK407, in which the coiled-coil region was disrupted, suppressed sec34-1 and sec34-2. Only the ORF of SEC34 is shown. (C) The sec34-1 and sec34-2 mutants encode truncated proteins of Sec34p. The base pairs and the corresponding amino acids of Sec34p that are changed in sec34-1 and sec34-2 are indicated with arrows.