Studies On The Taxonomy And Systematology Of Pseudokeronopsis And Holosticha (Protozoa, Ciliophora) Using Molecular Biological Techniques

Ciliated protozoa is the most complex and highly differentiated among single-celled organisms. Owing to their special nuclear dualism, complicated morphogenetic process and unique sexual reproduction (conjugation), ciliates play important roles in molecular biology, cell biology and researches on relationships between nucleus and cytoplasm.However, lots of morphological close-related species or sibling species need reassessment due to the insufficient and weak morphological and morphogenetic features. With molecular biological methods (RAPD, PCR-RFLP, PCR-SSCP, SSrRNA genes and ITS1-5.8S-ITS2 genes comparisons), this work resolved some confusions of morphological taxonomy and systematology of lower taxa within the Holosticha and Pseudokeronopsis at the genetic level, which included, at the species level– an examination of variation within and between morphologically close-related species based on RAPD fingerprinting and PCR-RFLP riboprinting; and above the species level– a re-construction of phylogenetic positions and evolutionary relationships within this group inferred from SSrRNA gene sequences. We also discussed the influence in the construction of phylogenetic trees.Taxonomy1. The SSrRNA genes were sequenced and analyzed for two populations of the marine hypotrichous species, Pseudokeronopsis flava. The results demonstrate the sequences of two populations differ one to another in two nucleotides, while two clones of the pop. II show completely the same sequences. Using four different random primers, the result of RAPD fingerprinting indicates that the differences between the band patterns of the two populations are exiguous, which indicates that this fingerprinting method is reliable in separating strains of these...