Studies On The Phylogeny Of Haptorida And Prostomatida(protozoa, Ciliophora) Using Gene Sequences

Ciliated protozoa is one kind of the single-celled organisms, and also the most complex andhighly divergent group. Ciliates belong to the eukaryotes group “Alveolata, Ciliophora”.During at least one period of ciliates’ life cycle, they have different kinds of cilia, that is whythey are called ciliates. We can find these organisms from most of the water habitats, only afew of them are influenced by environmental factors. They have very special nuclear dualism(the macronuclear is for nutrition as well as the micronuclear for reproduction), verycomplicated organell， cytoskeleton structures and infraciliature. Ciliates are importantorganisms for studying molecular biology, cell biology and relationships between nucleus andcytoplasm，parasitic and commensal ecologies, especially in the eukaryotic biologicalevolution.However, due to their complex life cycle and high diversity, taxonomy and phylogeneticassignments of some ciliated species are not developed very well. Though studies of theciliates have been carried out for years, most main groups’ phylogeny still remain confused.Therefore, more researches are needed to reveal the systematic relationships amongCiliophora. In this work we sequenced31SSU rRNA, LSU rRNA, ITS1-5.8S-ITS2genes ofprostomes and haptorids, and construct systematic trees in order to resolve confusions ofmorphological studies and molecular positions of some major taxa.Based on the SSU rRNA, LSU rRNA, and ITS1-5.8S-ITS2gene sequencing and overallanalyses, this work has already classified some taxonomy and phylogenetic positions of13strains of19species, with in two classes.