Journal: Scientific Reports
Article Title: Molecular determinants of SR-B1-dependent Plasmodium sporozoite entry into hepatocytes
doi: 10.1038/s41598-020-70468-2
Figure Lengend Snippet: A key domain within the SR-B1 apex regulates P. berghei infection. (A) Mouse and human protein sequence alignment of the apical region AA 132–223 with the corresponding predicted human secondary structure (alpha helices in red and beta strand in blue). Identical, similar and different amino acids are represented in black, blue and red respectively. Short domains D1, D2 and D3 are delimited by boxes. (B) Predicted tertiary structure of D1, D2 and D3 chimeras by homology modeling, highlighting the segments of mouse (orange) or human (blue) origins. (C) Top views of the electrostatic surface potential of the D1, D2 and D3 chimera apices. Values are in units of kT/e at 298 K, on a scale of − 2 kT/e (red) to + 2 kT/e (blue). White color indicates a neutral potential. Black circles highlight differential electrostatic surface potentials between the different chimeric constructs at the top of the “apex” region. (D) CD81KOH16 cells were transfected with hSR-B1, mSR-B1, D1, D2, or D3 chimeric constructs. Protein surface expression was analyzed using anti-hSR-B1 (“αH”, blue histograms) and anti-mSR-B1 (“αM”, orange histograms), 24 h after transfection. The grey histogram represents untransfected cells stained with the cognate antibody. (E) CD81KOH16 cells were transfected with hSR-B1, mSR-B1, D1, D2, or D3 chimeric constructs, or no plasmid as a control (Mock), and then infected with PbGFP sporozoites 24 h after transfection. The number of infected cells (EEFs) was determined by microscopy after UIS4 staining, 24 h after sporozoite addition (mean control values for each experiment: 59, 139, 214, 245, 299, 315 and 383 EEFs/well in hSR-B1-transfected CD81KOH16 cells). ns, non-significant; ** p < 0.01 (one-way ANOVA followed by Tukey’s multiple comparisons test).
Article Snippet: All incubations were performed at 4 °C in PBS supplemented with 3% (v/v) BSA for one hour with either “αH” anti-SR-B1 polyclonal rabbit serum or “αM” anti-SR-B1 polyclonal rabbit antibodies NB400-113 (Novus Biological).
Techniques: Infection, Sequencing, Construct, Transfection, Expressing, Staining, Plasmid Preparation, Control, Microscopy