Structure–function analysis and genetic interactions of the Yhc1, SmD3, SmB, and Snp1 subunits of yeast U1 snRNP and genetic interactions of SmD3 with U2 snRNP subunit Lea1

Effects of simultaneous Sm site mutations in SmD3 and SmB. SMD3 (WT) and SMD3-Ala alleles on CEN LEU2 plasmids were cotransformed with SMB1 (WT) and SMB1-Ala alleles on CEN HIS3 plasmids into a yeast smd3▵ smb1▵ p(CEN URA3 SMD3 SMB1) strain. The indicated viable FOA-resistant strains recovered after plasmid shuffle were spot tested for growth on YPD agar at the temperatures specified. SMD3 SMB1 allele pairs listed at the bottom failed to complement smd3▵ smb1▵ in the plasmid shuffle assay and were deemed synthetically lethal.