Figure 2. Spindle-independent cleavage furrow positioning.
(a) Sas-4 mutant neuroblast lacks astral microtubules, yet still establishes basal Myosin localization and basal furrow position (100%, n=158).
(b) Colcemid-treated rod mutant neuroblast lacks all spindle microtubules, yet still establishes basal Myosin localization and basal furrow position (100%, n=7).
(c) Colcemid-treated wild type neuroblast lacks all spindle microtubules, remains arrested at metaphase, and does not establish basal Myosin localization or initiate furrow formation (100%, n=7).
A schematic of each experiment is shown to the left (apical/basal polarity, blue/red; microtubules, gray). All genotypes imaged in late second/early third larval instar brains.
Scale bars: 10μm. Time in min:sec.