When a team of planetary scientists led by Joshua Colwell of the University of Colorado in Boulder modeled the most likely orbits of the dust, they concluded that 80% of the particles move in "retrograde" orbits--counter to Jupiter's spin and the orbits of its major moons.
In this case, actin polymerization and filaments growth happen predominantly at the tip of the spine, therefore one would expect most of the filaments to move in retrograde direction.
The filaments moving in retrograde direction outnumbers those in anterograde direction, therefore, on average, F-actin filaments in dendritic spines flows in a net retrograde direction.
Thus, to a hypothetical observer on Mercury, the Sun appears to move in a retrograde direction.
We found that single actin molecules at the lamellipodia continuously move in the retrograde direction at a rate of 2-3 µm/s (Figure 1B), similar to the results from earlier measurements [25], [26].
Surprisingly, it can instead 'jump' to the axon of a neighbouring neuron and then move in a retrograde fashion to the cell body.
Mitochondria with high membrane potential preferentially migrate in the anterograde direction, whereas mitochondria with low membrane potential move in the retrograde direction.
Triton is unique among the large moons of the solar system in that it moves in a retrograde orbit i.e., one that is opposite the direction of Neptune's rotation.
Triton moves in a retrograde orbit around Neptune that is, opposite to the direction of the planet's orbit around the Sun and features plumes of material rising through its tenuous atmosphere from a surface whose temperature is only 37 kelvins (K; −393 °F, −236 °C).
Planetary scientists Craig Agnor of the University of California, Santa Cruz, and Douglas Hamilton of University of Maryland, College Park, report in today's issue of Nature that the pair may have wandered too close to Neptune, whose powerful gravity grabbed Triton when it was moving in a retrograde direction around its companion.
However, the nodes of the Moon's orbit are gradually moving in a retrograde motion, due to the action of the Sun's gravity on the Moon's motion, and they make a complete circuit every 18.6 years.
