TABLE 1.
Dynamics of mitochondrial motility in neurons of control, transgenic, and KO micea
| Lineb | Direction of motion | Moving speed (μm/s)c | Average speed (μm/s)d | Fme | No. of stopsf |
|---|---|---|---|---|---|
| Cnt | A | 1.91 ± 1.11 | 1.19 ± 0.50 | 0.72 ± 0.14 | 0.9 |
| Cnt | R | 1.74 ± 0.91 | 1.27 ± 0.29 | 0.65 ± 0.16 | 0.5 |
| HD16 | A | 1.33 ± 0.61 | 1.06 ± 0.60 | 0.66 ± 0.28 | 1.1 |
| HD16 | R | 1.28 ± 0.59 | 0.75 ± 0.46* | 0.66 ± 0.19 | 1.8 |
| HD72 | A | 0.92 ± 0.36* | 0.45 ± 0.22* | 0.56 ± 0.22* | 5.7* |
| HD72 | R | 0.82 ± 0.34* | 0.40 ± 0.30* | 0.46 ± 0.19* | 5.1* |
| Flox/− | A | 0.63 ± 0.27 | 0.30 ± 0.16 | 0.71 ± 0.18 | 2.8 |
| Flox/− | R | 0.80 ± 0.35 | 0.34 ± 0.11 | 0.45 ± 0.17 | 5.0 |
| KO | A | 0.53 ± 0.22* | 0.21 ± 0.14* | 0.51 ± 0.22* | 7.4* |
| KO | R | 0.53 ± 0.20* | 0.21 ± 0.12* | 0.42 ± 0.19 | 7.5* |
Mitochondrial speed progressively declines as the glutamine tract in htt increases or htt is lost.
Data were generated in primary striatal embryonic neurons (E17) from control FVB/N (Cnt), transgenic mice with full-length htt with 16 (HD16) and 72 (HD72) glutamines, and mice with 50% loss of wild-type htt (Flox/−) that are littermates of htt conditional KO mice expressing less than 50% endogenous htt.
Speed when moving represents the total distance divided by the time in motion. Here times does not include stationary phases. Data were calculated using 92 to 355 mitochondria from 10 to 16 neurons. *, P < 0.0001.
Average speed represents the total distance traveled by the mitochondria divided by the total time. This involves time both in movement and in stationary phases. *, P < 0.0001.
The Fm is the fraction of time that the mitochondrion is moving. *, P < 0.05.
Number of stops represents the average number of pauses by a mitochondrion. *, P < 0.0001. Data presented in the last three columns were generated from 10 randomly selected organelles observed in five random neurons.