TABLE 2.
Characteristics of NC mutant virions
| MLV virions | Packaging of genomic RNAa | Particle density (g/ml) | Particle diam (nm)b | Capsid core diam (nm) |
|---|---|---|---|---|
| Wild-type | ++ | 1.14-1.16 | 105 ± 4 | ND |
| C39S | −c | 1.14-1.16 | 107 ± 9 | ND |
| ΔNC(16-23) | −d | 1.13-1.15 | 126 ± 11 | Irregular cores |
| PR− | ++e | 1.14-1.16 | 112 ± 6 | 61 ± 5 |
| C17- | +e | 1.14-1.16 | 101 ± 6 | 54 ± 4 |
| C37- | ND | 1.11-1.13 (light) | 99 ± 5 | 50 ± 4 |
| C60- | ND | No visible particle |
a
The presence (++, 100%; +, ∼50%) or the absence (−, ≤1%) of viral genomic RNA is indicated. ND, not determined.
b
All the mutant particle sizes except that of C39S are significantly different from wild-type (P < 0.001) particle sizes.
c
See reference 22.
d
See reference 35.
e
Viral RNA content was determined by Northern blotting (data not shown) or by RNA end labeling (29).