A mitochondria-surrounded Balbiani body (q.v.) found in the pre-vitellogenic Xenopus oocyte (q.v.) that functions in the assembly and translocation of specific RNAs to the vegetal pole, where the germ plasm (q.v.) is formed. The mitochondrial cloud originates near the nuclear membrane during early oogenesis (q.v.), increases in size, and subsequently breaks down into smaller “islands” that become localized to the vegetal pole of the egg. See cytoplasmic localization, METRO, sponge body.
Subjects: Genetics and Genomics.