Fig. 6. CSN5 is necessary for Grk protein expression, not for grk transcription. (A-C) In situ localization of grk RNA. At stage 10, grk transcript accumulates at the dorsoanterior corner of wild-type and most CSN5-mutant oocytes (A,B). Occasionally, grk RNA is mislocalized, probably because of mislocalization of the oocyte nucleus (C). (D-F) Grk antibody immunostaining. In CSN5 GLC egg chambers, expression of Grk is reduced or more diffusely distributed than in wild type. (G) Northern blot analysis of grk mRNA levels. In CSN5 GLC ovaries, the level of grk mRNA (extracted from an equal number of ovaries) is similar to wild type and significantly higher than in grk null-mutant ovaries. (H) Western blot analysis of Grk protein level. The Grk antibody recognizes a 46-47 kDa band that is reduced in ovaries homozygous for a hypomorphic grk allele, grk^HK36, and strongly reduced in ovaries from CSN5 germline clones.