Apparent diffusion coefficient of oligo(dT) in nucleus

Value 0.6 µm^2/sec Range: ±0.1 µm^2/sec
Organism Rat Rattus norvegicus
Reference Politz JC, Tuft RA, Pederson T, Singer RH. Movement of nuclear poly(A) RNA throughout the interchromatin space in living cells. Curr Biol. 1999 Mar 25 9(6):285-91. p.287 left column top paragraphPubMed ID10209094
Method p.286 right column 2nd paragraph:"To track the movement of the hybridized probe in the nucleus, live cells containing caged FL–oligo(dT) [fluorescein-labeled oligo(dT)] or caged FL–oligo(dA) were visualized using an inverted microscope interfaced with laser light sources and a digital imaging system capable of high-speed image acquisition (see Materials and methods)."
Comments p.286 right column bottom paragraph:"To estimate the rate of oligo(dT) movement in the nucleus, the radial distance that signal traveled from the uncaging site (displacement) was measured in the seconds after uncaging (see Materials and methods). The mean square of the displacement varied linearly with time (R^2 = 0.985, Figure 2c) — a characteristic feature of diffusion [19]. [Investigators] calculated an apparent diffusion coefficient of 0.6 ± 0.1 µm^2/sec. To further test the finding that the poly(A) RNA was diffusing, [they] performed the same experiments at 23°C instead of 37°C. Energy-requiring transport would be expected to slow considerably at the lower temperature, whereas diffusion would not (between the narrow range of 296–310°K)." p.288 right column top paragraph:"The apparent diffusion coefficient of 0.6 µm^2/sec estimated here was measured over relatively large distances (~5 µm) at a slower sampling rate, and therefore more accurately represents a value for long-range poly(A) RNA diffusion in the nucleus." Cells studied were rat L6 myoblasts
Entered by Uri M
ID 111845