Table 1. Diffusion coefficients of Dy647-PI3Kβ (WT and SH2 domain mutants) bound to membrane-tethered tyrosine phosphorylated peptides.
| protein visualized | pY/µm2 | τ1±SD (s) | τ 2±SD (s) | α(τ)±SD | AVEDT (s) | D1 ±SD (µm2/sec) | D2 ±SD (µm2/s) | α(D)±SD | MEDIAN step (µm) |
|---|---|---|---|---|---|---|---|---|---|
| PI3Kβ (WT) | 250 | 0.58±0.28 | 1.78±0.58 | 0.60±0.37 | 1.00±0.09 | 0.39±0.07 | 1.45±0.09 | 0.29±0.08 | 0.37±0.02 |
| PI3Kβ (WT) | 573 | 0.39±0.06 | 1.37±0.14 | 0.27±0.02 | 1.12±0.09 | 0.28±0.06 | 1.15±0.14 | 0.22±0.04 | 0.35±0.01 |
| PI3Kβ (WT) | 1226 | 0.36±0.13 | 1.29±0.06 | 0.30±0.09 | 1.05±0.11 | 0.20±0.02 | 1.18±0.09 | 0.16±0.02 | 0.36±0.02 |
| PI3Kβ (WT) | 2935 | 0.44±0.11 | 1.53±0.38 | 0.47±0.25 | 1.00±0.07 | 0.28±0.09 | 1.09±0.12 | 0.26±0.09 | 0.33±0.01 |
| PI3Kβ (WT) | 6661 | 0.46±0.08 | 1.28±0.16 | 0.61±0.13 | 0.82±0.11 | 0.35±0.17 | 1.28±0.34 | 0.35±0.18 | 0.34±0.01 |
| PI3Kβ (WT) | 14944 | 0.55±0.11 | 1.44±0.56 | 0.54±0.22 | 0.91±0.09 | 0.45±0.15 | 1.40±0.54 | 0.48±0.06 | 0.33±0.05 |
| PI3Kβ (WT) | 14944 | 0.49±0.17 | 1.38±0.19 | 0.35±0.17 | 1.10±0.04 | 0.32±0.04 | 0.99±0.12 | 0.40±0.11 | 0.30±0.02 |
| PI3Kβ (nSH2*) | 14944 | 0.23±0.02 | 1.48±0.23 | 0.86±0.03 | 0.45±0.06 | 0.38±0.09 | 1.45±0.25 | 0.41±0.18 | 0.34±0.01 |
| PI3Kβ (cSH2*) | 14944 | 0.38±0.08 | 1.54±0.55 | 0.76±0.1 | 0.65±0.08 | 0.34±0.13 | 1.12±0.29 | 0.43±0.15 | 0.30±0.04 |
SD = standard deviation from 3-5 technical replicates. n = 331 – 1909 total particles for each technical replicate. steps = 4277 – 39378 total particle displacements measured for each technical replicate. Alpha (αt) equals the fraction of molecules with the characteristic dwell time, τ1 (DT = dwell time). The fraction of molecules with the characteristic dwell time, τ2, equals 1-αt. Alpha (αD) equals the fraction of molecules with the characteristic diffusion coefficient, D1. The fraction of molecules with diffusion coefficient, D2, equals 1-αD. Membrane composition: 96% DOPC, 2% PI(4,5)P2, 2% MCC-PE.