Table 1.

Details of the selected deletion mutants verified by DNA sequencing

	Amino acids	Size (kDa)	Sequence	Extra amino acids	Sec1p-binding
N-terminal fragments	1–194	26	—ASSGVID*	2	+
	1–158	22	—RPTRWID*	3	+
	1–146	20	—HTSSSSD*	1	+
	1–131	18	—PEYTPAS*	0	+
	1–96	15	—KQNSLID*	3	+
	1–78	13	—KEDLPND*	1	+
	1–46	9	—GDTVNTD*	1	−
C-terminal fragments	9–210	25	*QEGSGR—	0	+
	35–210	22	*IKAEKD—	0	+
	78–210	17	*NERKIL—	0	±
	105–210	14	*NRRKAS—	0	−
	136–210	11	*DIYNNH—	0	−

In the set of N-terminal fragments, there can be up to three extra amino acids at the C-termini, depending on which stop codon in the transposon end matches the reading frame of the encoded protein. The bolded sequences correspond to Mso1p, and extra C-terminal amino acids are shown in regular font. The predicted size of each fragment includes the N-terminal His₆ tag. Asterisks denote the protein termini. The result of Sec1p binding assay is denoted as + (binding), −(no binding), ± (intermediate binding).