Fig. 1. cni-related and cni show partial redundancy in the soma but not the germline. (A) Wild-type head. Ocellar (arrowhead), interocellar (black arrow), and post-vertical bristles (white arrow) are marked. (B) cni^AR55/cni^AR55 head. Ocellar (arrowhead), interocellar (black arrow) and post-vertical bristles (white arrow) are missing and the eyes are rough. (C) cni^AR55/cni^AR55 rough eye phenotype with fusion of ommatidia (white arrow), specification of ommatidia with aberrant numbers of cone cells (white arrowhead), and missing (black arrow) or ectopic (black arrowhead) interommatidial bristles. (D) The pcni::Cnir transgene (cnir ORF under cni control) rescues ocellar (arrowhead) and post-vertical (white arrow), but not intraocellar bristles (black arrow) or the rough eye phenotype. (E) Homozygous cni^AR55/cni^AR55 wing. Vein 2 is truncated before it reaches the margin (arrow). (F) One copy of the pcni::Cnir transgene suppresses the cni wing phenotype (arrow). (G) Wild-type egg with two large dorsal respiratory appendages and an anterior micropyle. (H) Egg from a cni^AR55/cni^AR55 mother. Owing to the loss of Grk signalling, the egg is ventralized and both ends differentiate into anterior structures. (I) Egg from a cni^AR55/cni^AR55 female carrying a pCnimyc transgene. Establishment of the anteroposterior axis is completely rescued and that of the dorsoventral axis largely rescued. (J) Egg from a cni^AR55/cni^AR55; pcni::Cnir female. Expression of cnir under control of cni promotor and UTR sequences fails to rescue Grk signalling.