Journal: Molecular Microbiology
Article Title: UAP56 is a conserved crucial component of a divergent mRNA export pathway in Toxoplasma gondii
doi: 10.1111/mmi.13485
Figure Lengend Snippet: Establishment of a conditional Cas9 (ddCas9). A. Western blot showing ddCas9‐FLAG overexpression. Parasites were induced for indicated times with 1µM of Shld1 prior protein extraction. RH‐Δhxgprt strain was used as control (first and second lanes ‐ wild type‐ wt) Aldolase: Loading control. B. i) Nuclear localization of Cas9 in RHddCas9 parasites after addition of 1 µM Shld1 for 24 h. Nuclear and apicoplast DNA staining with DAPI: in blue. Scale bar: 10µm. ii) Co‐localization map, showing in grey the areas where there was co‐localization with an M2 of 0.8. Graph represents the areas where there was a signal for green (green line) and areas where there was signal for blue (blue line). y ‐Axis: intensity level; x ‐axis: distance in microns. C. Plaque assays for parental RHddCas9 and RHddCas9‐ gap40 gRNA strains. Both parasite strains were grown on human foreskin fibroblasts, in the presence or absence of 1 µM of Shld1, as indicated, for 108 h. −, not induced; +, induced. Scale bar: 500 µm. D. Immunofluorescence assay of parental RHddCas9 and RHddCas9‐ gap40 sgRNA strains in the presence or absence of Shld1. Collapsing vacuoles with a significant reduction of GAP40 signal were only observed in induced parasites that expressed the specific sgRNA against gap40 . Scale bar: 8 µm. E. mRNA distribution was analyzed in RHddCas9, RHddCas9‐ gap40 gRNA and RHddCas9‐ uap56 gRNA strains after incubation for 4 h with 1 µM Shld1 and further incubation for 48 h in media. The analysis was performed by fluorescent in situ hybridization (FISH) using oligodT‐Alexa594 as probe, in red. Nuclear and apicoplast DNA was staining with DAPI: in blue. Scale bar: 5 µm. F. mRNA distribution and TgUAP56 protein presence analysis in RHddCas9‐ uap56 gRNA strain after incubation for 4 h with 1 µM Shld1 and further incubation for 48 h in media. i) The analysis was performed by immunofluorescence assay, α‐TgUAP56 in green, combined with fluorescent in situ hybridization (FISH) using oligodT‐Alexa594 as probe, in red. mRNA export blocking was observed in absence of TgUAP56 in induced parasites that expressed the specific sgRNA against uap56 . Nuclear and apicoplast DNA was staining with DAPI: in blue. Scale bar: 5µm. ii) Western blot to analyse TgUAP56 protein levels after 1 µM Shld1 incubation for 24 and 48 h. The protein was detected with anti‐TgUAP56. Aldolase was used as loading control. ddCas9‐FLAG was detected using antibody α‐Flag. −, not induced; +, induced.
Article Snippet: To generate conditional ddCas9 plasmid ( p5RT70DDmycFlagCas9 ) the synthetic cas9 expressing cassette from Lourido's lab (Addgene ID 52694 (Sidik et al ., )) was cloned into plasmid p5RT70ddmycGFPPfMyoAtailTy‐HX (Hettmann et al ., ) using NcoI‐NotI restriction sites.
Techniques: Western Blot, Over Expression, Protein Extraction, Control, Staining, Immunofluorescence, Incubation, In Situ Hybridization, Blocking Assay