TABLE 2:
Effects of mutations in TM1 on gap junction intercellular communication produced by homomeric or heteromeric channels.
| Incidence of coupling | |||||
|---|---|---|---|---|---|
| Expressed construct | Neurobiotin (287 Da/+1) |
Ethidium (314 Da/+1) |
YO-PRO-1 (375 Da/+2) |
Propidium (414 Da/+2) |
Lucifer yellow (430 Da/–2) |
| None | 0 (15) | 0 (5) | 0 (5) | 0 (6) | 0 (15) |
| Cx26 | 100 (30) | 100 | 100 | 100 | 100 (30) |
| Cx26GTAV | 0 (15) | ND | ND | ND | 0 (15) |
| Cx26-GFP | 100 (16) | 100 (9) | 100 (7) | 100 (6) | 100 (16) |
| Cx26V37I-GFP | 93.3 (15) | 100 (7) | 0 (10) | 0 (7) | 13.3 (15) |
| Cx26V37C-GFP | 70.6 (17) | ND | ND | ND | 29.4 (17) |
| Cx26A40G-GFP | 5.3 (19) | 0 (8) | 0 (9) | 0 (6) | 5.3 (19) |
| Cx26A40C-GFP | 0 (13) | ND | ND | ND | 0 (13) |
| Cx26 + Cx26V37I-GFP | 100 (17) | ND | ND | ND | 85 (17) |
| Cx26 + Cx26A40G-GFP | 80 (10) | ND | ND | ND | 80 (10) |
| Cx43 | 100 (54) | ND | ND | ND | 98.1 (54) |
| Cx43 + Cx26V37I-GFP | 85.7 (7) | ND | ND | ND | 85.7 (7) |
| Cx43 + Cx26A40G-GFP | 75 (8) | ND | ND | ND | 75 (8) |
The incidence of coupling is reported as the percent of microinjections in which transfer of the gap junction tracer was observed from the injected cell to its neighbors in untransfected HeLa cells (None, mock-transfected) and in HeLa cells transfected with each of the DNA constructs. The number of microinjected cells is indicated in parentheses. The molecular weights and charge of the gap junction tracers are indicated in parentheses underneath the tracer names. ND, not determined.