BP-pacFA-protocol
ref:
Trifunctional Sphinganine: A New Tool to Dissect Sphingolipid Function
In Vivo Profiling and Visualization of Cellular Protein–Lipid Interactions Using Bifunctional Fatty Acids
copper sulfate, 探索
TCEP(Tris(2-carboxyethyl)phosphine hydrochloride), SIGMA, C4706, (L-Ascorbic acid, SIGMA, A92902)
TBTA(Tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine), SIGMA, 678937
Azide-fluor 488, SIGMA, 760765
preparation:
500mM copper sulfate stock: 7.98g溶解到80ml去离子水中, 定容到100ml, 常温保存
100mM TBTA stock: 1 mg + 18.8 μl DMSO, stored at -20
2mM azide-A488 stock: 1 mg + 870 μl DMSO, stored at -20
click mix:
1mM copper sulfate
1mM TCEP (or 1mM sodium ascorbate)
100μM TBTA
2μM A488-azide (or 2μM others)
in PBS
当天配置50mM的抗坏血酸, 每10mg加1130μlPBS, 取所需量的体积用PBS稀释到1mM, 再加入其他试剂
- 100μM OA诱导脂滴,具体时间视细胞系决定,Hela细胞24h,Huh7细胞3h(为了成像,结束诱导时具有60%左右的confluence,据此处把握一开始seeding的细胞量)
- wash twice with HBSS
- incubate with 10μM BP-pacFA in HBSS for 10min at 37°C
- expose to 525nm light for 2min to uncage the probe
- return to the incubator for varying amounts of time to allow for metabolism
- expose to 365nm light for 5s to cross-link on ice, and immediately replaced with ice-cold methanol (-20°C) for 20min on ice
- wash three times with CHCl3/MeOH/AcOH (10:55:0.75, v/v/v) for 1min each time at RT
- wash three times with PBS for 5min each time
- add click mix (400μl for 24-well plates, 70μl for 96-well plates)
- incubated for 1 h in the dark on a shaker
- wash twice with PBS to remove the click mix
Antibody staining
- blocking buffer (2% BSA, 0.1% Triton-X-100 in PBS) was added. Cells were blocked for 1 h before the addition of primary antibodies
- incubate with primary antibody