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Fig. 2. The generation of a niche during gonadal development. (A) An early pupal
gonad (0-2 hours after puparium formation) showing the disposition of terminal
filament cells and cap cells, and germline cells. This focal plane depicts
five ovarioles. (B,C) Magnification of ovarioles from 0-2 hour pupal gonads.
(B) Germline cell in metaphase. The mitotic spindle is oriented so that one of
the daughter cells will remain in contact with the cap cells. (C) Cystoblast
dividing; the mitotic spindle of these differentiating cells is oriented
randomly with respect to the cap cells. In this particular case it is
perpendicular to the anterior-posterior axis of the ovariole. Red: tubulin
staining to show cell shapes and mitotic spindles; green: membrane-bound GFP
driven by a germline specific promoter to label germline cells; blue:
phosphohistone H3 to label dividing cells.