Supplemental Materials

This article contains the following supporting material:

• Figure S1 - Septins Exhibit Co-ordinate Expression

  (A&B) HeLa cells were transfected with anti-Sept6 siRNA (GAGCUAAAGAUCCGAAGAGdTdT or CGGAGUCCAGAUCUAUCAGdTdT, referred to as Sept6 #1 and #2, respectively) as described in Materials & Methods and stained for septin expression after 72hrs. Ran was used as a loading control. (A) Septin expression following transfection with anti-Sept6 siRNA. Targeted depletion of Sept6 causes loss of Sept2 and Sept7 expression. (B) Bands from 3 immunoblots were scanned and their intensity quantified and normalized for Ran expression. Each condition is shown as the ratio of septin-depleted signal to control-transfected cells from the same experiment. Bars = S.E.M. (n = 3).

• Figure S2 - MAP4 Knockdown Results in Decreased MAP4 Staining and Altered Cellular Morphology

  HeLa cells were transfected with anti MAP4 siRNA as described in Materials & Methods and stained for MAP4 expression after 72hrs. Other cells were stained for α-tubulin to visualize the effect of MAP4 depletion on the tubulin cytoskeleton. Though MAP4 was not visible decorating MTs under the conditions used to stain, the antibody signal was greatly attenuated in the MAP4-depleted cells, indicating the efficacy of knockdown and specificity of the antibody. MAP4-depleted cells are smaller and more round than control-transfected cells, and they lack peripheral MTs. Bar = 10 μm.

• Figure S3 - Phalloidin staining and efficacy of knockdown from Figure 9

  For clarity, only the cellular outlines were shown in Figure 9A. (A) Phalloidin-stained HeLa cells, showing the same fields as in Figure 9A. Bar = 10 μm. (B) Following transfection with control, anti-Sept7-, anti-MAP4-, or anti-Sept7- + anti-MAP4 siRNA, half of the HeLa cells were lysed. Four μg of total cell lysate for each transfection were separated, transferred to nitrocellulose, and probed for MAP4, Sept6, and Ran as described in Materials & Methods.