Various MAPs are associated with the Q-MT bundle and influence its shape. (A and B) Mto2 relocalizes from the nuclear membrane onto the Q-MT bundle. (A) Cells expressing Mto2-GFP (green) and RFP-Atb2 (red) are shown. Colocalization coefficient between Mto2-GFP and RFP-Atb2 are indicated (see Materials and methods for details). (B) Line-scan analyses (right) indicate that Mto2 localizes at MT extremities within the Q-MT bundle. (C) Numerous MAPs colocalize with the Q-MT bundle. Cells expressing RFP-Atb2 and the indicated MAP fused to GFP were grown 5 d and imaged. Graphs are line scan analyses of the red and green fluorescence. In B and C, data are representative of the fluorescence intensity variations measured out of four experimental repeats. (D–F) The Q-MT bundle shape is influenced by the deletion of specific MAPs. (D) Q-MT bundle was imaged in 7-d-old cells expressing GFP-Atb2 and deleted for the indicated MAP. (E and F) Q-MT bundle length (n > 200; E) and Q-MT bundle intensity (n > 100; F) were measured in the indicated mutants. ***, P < 10−4. Blue and red asterisks shows positive and negative difference, respectively. Bars, 2 µm.
