Journal: Journal of Lipid Research
Article Title: A novel mutation, Ile344Asn, in microsomal triglyceride transfer protein abolishes binding to protein disulfide isomerase
doi: 10.1016/j.jlr.2024.100725
Figure Lengend Snippet: Increased expression of Ile344Asn did not improve the lipid transfer activity and apoB secretion in Mko-3 cell. Mko-3 cells were transfected with either 2 μg of plasmid expressing WT MTP or 4 μg, 6 μg and 9 μg of Ile344Asn MTP. After 48 h, the media was replaced with fresh DMEM with 10% FBS and incubated overnight. The cells were collected, homogenized, and centrifuged at 12,000 rpm or 13,500 g for 10 min at 4°C. From the clear supernatant, 25 μg protein was separated on 8% SDS-PAGE and probed with anti-hMTP (A, top ), stripped, and probed with anti-β-actin antibodies for control (A, bottom ). For the TG transfer assay, 25 μg protein was used from the clear homogenate (B). Overnight-conditioned media was used to measure apoB-100 secretion by ELISA (C). For lipid transfer assays and MTP:PDI interaction studies, purified proteins were separated on SDS-PAGE and probed for anti-hMTP followed by anti-PDI antibody (D). Different aliquots of purified proteins were used to measure TG and PL transfer activity (E–F). The bars and error bars represent mean ± SD. To calculate the significance, one-way ANOVA nonparametric (multiple comparison) or two-way ANOVA was used. ∗∗∗ and ∗∗∗∗ represent P < 0.001 and P < 0.0001, respectively. The data are representative of three independent experiments performed with biological triplicates.
Article Snippet: Rabbit polyclonal anti-β-actin primary antibody (Cell Signaling #4967S) was used to detect the internal reference β-actin.
Techniques: Expressing, Activity Assay, Transfection, Plasmid Preparation, Incubation, SDS Page, Control, Enzyme-linked Immunosorbent Assay, Purification, Comparison