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Fig. 6. The requirement of tkv for clonal expansion of GSCs during niche
formation. Both germaria are labeled for lacZ (red), Hts (green) and
DNA (blue). lacZ-negative mutant tkv PGCs were generated
before the late third instar larval stage, and mutant tkv GSCs in the
adult ovary were subsequently identified by loss of lacZ expression.
(A) A germarium carrying three lacZ-positive wild type GSCs (outlined
by unbroken lines) and lacZ-negative tkv mutant germline
cysts (outlined by a broken line). The mutant tkv cysts were most likely
derived from a lost mutant tkv GSC. (B) A germarium carrying a
lacZ-negative tkv mutant GSC (outlined by a broken line), a
lacZ-positive wild type GSC (outlined by an unbroken line), and a
mutant tkv cyst (arrow). Scale bar: 10 µm.