IDENTIFYING AND DISTINGUISHING SIBLING SPECIES IN THE TETRAHYMENA-PYRIFORMIS COMPLEX (CILIOPHORA, OLIGOHYMENOPHOREA) USING PCR RFLP ANALYSIS OF NUCLEAR RIBOSOMAL DNA/
Ca. Jerome et Dh. Lynn, IDENTIFYING AND DISTINGUISHING SIBLING SPECIES IN THE TETRAHYMENA-PYRIFORMIS COMPLEX (CILIOPHORA, OLIGOHYMENOPHOREA) USING PCR RFLP ANALYSIS OF NUCLEAR RIBOSOMAL DNA/, The Journal of eukaryotic microbiology, 43(6), 1996, pp. 492-497
We describe a riboprinting strategy for identifying and distinguishing
among sibling species in the Tetrahymena pyriformis complex. It invol
ves use of the polymerase chain reaction to amplify a large segment of
the nuclear ribosomal DNA and internal transcribed spacers, and diges
tion of this DNA with restriction enzymes. Unique restriction fragment
length patterns or haplotypes were then used to distinguish species i
nto: (1) six taxa that were identifiable to the species level, (2) eig
ht taxa that were separated into four pairs, and (3) a group of eight
taxa that were identical to each other. The latter result indicates th
at a more variable molecule is needed to distinguish the most closely
related species in the complex. There was no intraspecific variation b
etween two strains from one species (Tetrahymena thermophila) nor amon
g multiple isolates from another species (Tetrahymena empidokyrea). Th
is approach provides an alternative to traditional techniques for iden
tifying T. pyriformis species that require living reference specimens
and/or that reveal high levels of intraspecific variation.