Knockdown of Tsp29Fb affects cell morphology and cooperates with dRas^V12 in tumor growth and invasion.

(a) Co-expression of Tsp29FbRNAi (tspi) with dRasV12 using the ey-FLP-out system results in neoplastic transformation and overgrowth of larval eye-antenna discs (right), whilst tspi expression shows no overt phenotype (left) and dRasV12 leads to hyperplastic larval discs without interfering with pupariation. Magnifications 20X. GFP (green) shows the ey-FLP-out tissue. The tissue is stained with Phallodin-TRITC (red) to detect F-actin. (b) tspi dRasV12 third instar larvae exhibit massive overgrowth and giant tumors. Magnifications 4X. (c) ey-FLP-out tspi, dRasV12 and tspi dRasV12 third instar larval eye discs propagated at 29°C, showing that tspi dRasV12 GFP+ cells have migrated into the VNC. Arrows show tissue disorganisation and tumor fusion to optic lobes (far right) with ventral nerve cord invasion (second from the right). (d) Pupal eye discs containing MARCM control or tspi clones (bottom, marked by the presence of GFP, and the clonal boundary is outlined by a yellow dotted line). Dlg is downregulated and mislocalized from the apical cortex upon Tsp29Fb knockdown. (e) Control MARCM adult eyes and tspi MARCM adult eyes. Tsp29Fb knockdown in clones results in a small rough eye phenotype.