Robeson II, M.S.*; Garey, J.R.: The mitochondrial genome of the rotifer Brachionus plicatilis.

There are no published sequences of the complete mitochondrial genome from a rotifer. The mitochondrial genome of different isolates of the rotifer Brachionus plicatilis vary in size from 16-26 kilobases (kb). About 12 kb from an isolate with a genome totaling approximately 16-20 kb was sequenced. The contiguous stretch contains the genes for 11 tRNAs, 2 rRNA genes, 4 protein coding genes (NADH dehydrogenase 1, NADH dehydrogenase 2, ATPase 6, and cytochrome b). The remaining sequence appears to be non-coding. The expansion or contraction of this non-coding region may account for the variation in mitochondrial genome size from different isolates. Currently an attempt is being made to PCR amplify and sequence the remaining mitochondrial genome. The order of the genes and the sequences of the genes will provide phylogenetic information to help elucidate the relationship of rotifers to other metazoans. The sequence of this genome will make it easier to PCR amplify mitochondrial genes from other rotifers, facilitating studies of the evolutionary relationships among rotifers.