A PROPOSAL FOR TYPICAL EUKARYOTIC MEIOSIS IN MICROSPORIDIANS

A review of key publications concerning the biology and life cycles of microsporidians has led us to challenge recent proposals that they ex hibit a unique process of meiosis when compared with other eukaryotes. The basic data used to support this challenge are the same as those u sed by researchers suggesting atypical meiosis, but the data are analy zed from a different viewpoint. Arguments are put forward to support a testable hypothesis that meiosis in microsporidians is identical to t hat which occurs in other eukaryotes. It is proposed that confusion re sulted because two separate cytological developmental sequences for di plokaryotic meronts in mosquito fat body cells were previously interpr eted as a single sequence. By rearrangement of the original data into two developmental sequences. one abortive and the other for typical me iosis, a better fit was obtained between cytological stages and microp hotometric measurements of nuclear DNA content. This improved data fit and the existence of similar nuclear developmental sequences in the f ungi are used to support our hypothesis.