Light chain 2 is a Tctex-type related axonemal dynein light chain that regulates directional ciliary motility in Trypanosoma brucei
Fig 5
Optically trapped LC2 KD and FLAM3-LC2 KD cells showed upregulated ciliary beat frequency.
A. Schematic of a T. brucei cell (gray) trapped by a low power (~20 mW) optical tweezer (red). B. Brightfield image of an uninduced FLAM3-LC2 KD cell taken near the coverslip, thus enabling direct visualization of the trap location and aligning the cell in the imaging plane. The identified trap location on a trypanosome cell (red arrowhead) is typical of all cells we trapped. Scale bar = 5 μm. C. Typical maximum projection (intensity inverted) of a movie (2 s) showing a trapped FLAM3 KD cell as it rotates about the trap center (red arrowhead). Scale bar = 5 μm. D. Typical power spectral densities (PSD) of a trapped cell with its cilium beating (FLAM3-LC2 KD/LC2 OE cell, orange), a trapped cell with its cilium not beating (FLAM3-LC2 KD/LC2 OE cell stalled at the bottom of the imaging chamber, purple), and background trap noise (gray, about six orders of magnitude smaller than the PSD of the cell with a beating cilium at the beat frequency). Peaks in the PSD represent the characteristic cell rotation rate (blue arrowhead) and ciliary beat frequency (red arrowhead). Each PSD represents the average of 3 spectra (1 second of data, each). E. Ciliary beat frequency, fω, of multiple cell lines obtained from the higher of the two characteristic frequencies from the PSD analysis. The error bars represent the SEM and *** represents p-values < 0.0001 and ns represents p-values > 0.05 from two-tailed paired t-tests. N = 25, 86, 75, 85, and 96 for uninduced, LC2 KD, FLAM3 KD, FLAM3-LC2 KD, and FLAM3-LC2 KD/LC2 OE cells, respectively.