Figure 1.

Snp1 C-terminal truncations suppress tgs1∆ cold sensitivity. (A) The amino acid sequence of the 300-aa S. cerevisiae Snp1 protein is aligned to the homologous segment of the 437-aa human U1-70K polypeptide. Positions of side chain identity/similarity are indicated by • above the alignment. Arrowheads indicate the boundaries of the C-terminal truncations of Snp1. (B) The wild-type and truncated SNP1 alleles were tested for activity by plasmid shuffle in snp1∆, snp1∆ mud2∆, snp1∆ nam8∆, snp1∆ mud1∆, and snp1∆ tgs1∆ strains. Viable FOA-resistant snp1∆ strains bearing the indicated SNP1 allele on a CEN HIS3 plasmid in an otherwise wild-type (top panel), mud1∆, or nam8∆ background as indicated were spot-tested for growth on YPD agar at the temperatures specified. Synthetic growth defects are denoted by •. snp1∆ tgs1∆ strains bearing the indicated SNP1 allele on a CEN HIS3 plasmid were spot-tested for growth on YPD agar at the temperatures specified (bottom panel). Suppressors of the tgs1∆ cs phenotype are denoted by arrowheads.