TABLE 3.
Rates of 125I-HA endocytosis by 190-HARE CD variants Cells expressing the indicated 190-HARE mutants, WT, or EV were assessed for specific 125I-HA endocytosis and normalized to total protein and then cell number, and HARE expression relative to WT as described under “Experimental Procedures.” Values are the mean ± S.E. (n = 6–9).
| 190-HARE mutant | Specific 125I-HARE | Relative HA uptake |
|---|---|---|
| fmol/106 cells/WT HARE/h | % | |
| WT | 295 ± 5 | 100 |
| EV | 0.5 ± 0.3 | 0.2 |
| ΔM1 | 151 ± 5a,b | 51 |
| ΔM2 | 180 ± 2b | 61 |
| ΔM3 | 129 ± 4a | 44 |
| ΔM4 | 351 ± 6 | 119 |
| ΔM1M2 | 182 ± 2 | 61 |
| ΔM1M2M4 | 172 ± 4 | 58 |
| ΔM1M2M3M4 | 21 ± 3 | 7 |
| Y2519A | 279 ± 19 | 94 |
| ΔM1M2M3 + Y2519A | 14 ± 2 | 5 |
a
Data indicate that the rates for the ΔM1 and ΔM3 mutants, compared with each other, were significantly different; p < 0.002
b
Data indicate that the rates for ΔM1 and ΔM2 mutants were significantly different; p < 0.001