Figure 2.

The majority of single U1 snRNPs was in a bound state. (A) Magnified view of a specific region of a cell nucleus. At many positions as marked by black arrows single U1 snRNPs were observed for extended periods of time at specific sites; scale bar, 1 μm. (B) The distance distribution of the single positions of 100 randomly selected immobile trajectories to their respective centers could well be described by a Gaussian distribution with a SD of 30 nm (dashed line). A slight deviation between fit and histogram occurred at distances greater than 60 nm.