Light micrograph of Antonospora locustae with pressure-induced polar tube eversion. The scale bar is 10 µm. (A) Many ungerminated spores (one example labeled U) and a few germinated spores, showing the residual spore wall (one example labeled G). (B) A germinated spore where the everted polar tube (PT) has extended far from the cell and can be seen to be many times the length of the spore. Copyright: 2009 Patrick Keeling

The genome sequence and gene predictions of Antonospora locustae were not determined by the JGI, but were downloaded from JBPC and have been published (Corradi N et al., 2007). Please note that this copy of the genome is not maintained by the author and is therefore not automatically updated.

Members of the phylum Microsporidia are highly successful, obligate intracellular eukaryotic parasites with remarkably small genomes of 2.3-20 megabases (MB). They infect nearly all the invertebrate phyla, most commonly arthropods, and all five classes of vertebrates. In agricultural settings, some microsporidial species serve as biological control agents of pests, including Antonospora locustae (Nolo Bait) while others are significant pathogens of beneficial insects. A survey of genomic sequences from Antonospora locustae, a microsporidian that is distantly related to E. cuniculi, suggested that this compaction has further effects on the evolution of microsporidian genomes. Specifically, this survey showed that the order of genes in the A. locustae and E. cuniculi genomes share a high degree of conservation, and that this conservation was correlated with short intergenic spaces. Conservation of gene order usually degrades rapidly in eukaryotic genomes leading to the suggestion that genome compaction could slow the rate of genome rearrangements. This comparison also challenged the hypothesis that the rate of genome evolution may be correlated with the rate of sequence evolution since the rate of sequence evolution between the two species is relatively high.