Evidence that the conserved N-terminal LSm domain is essential for translational repression and stimulation of mRNA decay by tethered Scd6-MS2-F <i>in vivo</i>.

(A) Diagrams representing the domain organization of full-length Scd6 (Scd6-MS2-F) or variants lacking amino acids 1–83 at its N-terminus (ΔLSm-Scd6-MS2-F) or amino acids 286–312 at its C-terminus (ΔRGG-Scd6-MS2-F), present in the corresponding fusions to MS2-F. MS2 and FLAG tags are not depicted. (B-F) Transformants of WT strain BY4741 containing the GFP reporter plasmid pJC429 and expression plasmids for MS2-F (pQZ130) and Scd6-MS2-F (pQZ127), and either ΔLSm-Scd6-MS2-F (pQZ139) (B, D-E) or ΔRGG-Scd6-MS2-F (pQZ142) (C & F) were analyzed for GFP protein (B-D & F) and mRNA (E) expression as in Fig 1B–1D. (G) Transformants of WT strain BY4741 harboring the lacZ reporter plasmid pQZ131 and the expression plasmids for MS2-F, Scd6-MS2-F, or ΔLSm-Scd6-MS2-F used in (B) were analyzed for β-galactosidase expression as in Fig 5B. Mean values (± S.E.M.s) were determined from at least four biological replicates. Determination of P-values from significance testing of differences in mean values in (D-G) using an unpaired Student’s t-test, were conducted as described in the supporting file S1 Text. P-values are summarized as: **, P <0.01; *, P <0.05.