A proposal for typical eukaryotic meiosis in microsporidians

Abstract

A review of key publications concerning the biology and life cycles of microsporidians has led us to challenge recent proposals that they exhibit a unique process of meiosis when compared with other eukaryotes. The basic data used to support this challenge are the same as those used by researchers suggesting atypical meiosis, but the data are analyzed from a different viewpoint. Arguments are put forward to support a testable hypothesis that meiosis in microsporidians is identical to that which occurs in other eukaryotes. It is proposed that confusion resulted because two separate cytological developmental sequences for diplokaryotic meronts in mosquito fat body cells were previously interpreted as a single sequence. By rearrangement of the original data into two developmental sequences, one abortive and the other for typical meiosis, a better fit was obtained between cytological stages and microphotometric measurements of nuclear DNA content. This improved data fit and the existence of similar nuclear developmental sequences in the fungi are used to support our hypothesis.