Fig. 2. Hypomorphic Khc alleles that block slow streaming did not block oskar mRNA localization. In situ hybridization with fluorescent oskar RNA probes in stage 10A-10B shows localization of oskar mRNA in oocytes with the indicated genotypes. (A) Wild type. (B,C) Some oskar accumulated and persisted at the centers of the hypomorphic mutant oocytes and concentrated strongly at the posterior (see also Fig. S2 in the supplementary material). (D) In Khc-null oocytes, oskar did not accumulate at either the center or posterior, but there was an elevated concentration around the cortex. Scale bar: 25 µm.