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Fig. 5. Classes of mutants affecting the localisation of both oskar and
bicoid mRNA. In situ hybridisations for bicoid are shown on
the left (A,C,E,G) and hybridisations for oskar are shown on the
right (B,D,F,H). (A,B) Wild-type egg chambers. (C,D)
boussole8F8-6. This mutant shows ectopic
localisation of oskar mRNA to the centre of the oocyte, and posterior
accumulation of bicoid mRNA in a subset of oocytes. (E,F)
abruzzi7C3-10 is a member of a large class of
mutants, in which the oocyte nucleus is frequently mislocalised (see arrow in
panel E) and bicoid mRNA associates with the cortex proximal to the
nucleus. In these mutants, oskar mRNA also fails to adopt a wild-type
localisation pattern. (G,H) mertz8077, an example of the
class of mutants in which both oskar and bicoid mRNAs fail
to localise to their respective poles and are diffuse in the oocyte.