Unexpectedly, RNAi targeting the Fos-dimerizing partner Jun neither improved larval viability nor reduced tumor invasiveness or photoreceptor differentiation (Fig. 3A,B, data not shown), although jun RNAi reproduced previously reported phenotypes (Jindra et al., 2004; Sekyrova et al., 2010; supplementary material Fig. S3D) and depleted the Jun protein (supplementary material Fig. S3E,F). Here, FOS is linked to neoplasm.