<i>Socs36E</i> mutant CySCs can self-renew without JAK/STAT signaling.

<p>All clones were generated by the MARCM technique and are positively-marked by the expression of GFP. A,B) CySC clones that express a dominant-negative form of Dome (<i>Dome</i>^Δ<i>cyt</i>) (A), which inhibits JAK/STAT signaling, or that are depleted for Stat92E (<i>UAS-Stat RNAi</i>) (B), are not recovered at 7 dpci. However, their differentiating cyst descendants are observed at this time point (A’,B’, arrow). C,D) By contrast, when <i>Socs36E</i> is also removed from <i>Dome</i>^Δ<i>cyt</i> (C, arrows) or from <i>UAS-StatRNAi</i> (D, arrows) CySC clones, these clones are now maintained as stem cells. E) <i>Socs36E</i> clones have elevated levels of Stat92E (E,E’, arrow) compared with wild type CySCs (E,E’, arrowhead). Note that GSCs have higher levels of stabilized Stat92E protein than wild type CySCs. F) Some <i>Socs36E</i>, <i>Dome</i>^Δ<i>cyt</i> CySCs have residual levels of stabilized Stat92E (F,F’, arrowhead) and some have undetectable levels of stabilized Stat92E (F,F’, arrow). G) <i>Socs36E</i>, <i>UAS-Stat RNAi</i> CySCs have undetectable Stat92E levels (G’, arrow) whereas wild type CySCs in the same testis have moderate to high levels of Stat92E (G’, arrowheads). H) Graph of CySC clone recovery rates at 2 (blue bars) and 7 (red bars) dpci. CySCs expressing <i>Dome</i>^Δ<i>cyt</i> or <i>UAS-Stat RNAi</i> are not recovered at 7 dpci. By contrast, <i>Socs36E</i>, <i>UAS</i>-<i>Dome</i>^Δ<i>cyt</i> CySCs are recovered at robust levels at 7 dpci. <i>Socs36E</i>, <i>UAS-StatRNAi</i> CySCs are maintained at moderate levels at 7 dpci. Vasa is red in A-G. Tj is blue in A-D and Stat92E is blue in E-G. The hub is outlined by a dotted line. Scale bar = 5 μM.