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Assessment of DNA Contamination in RNA Samples Based on Ribosomal DNA
Published on: January 22, 2018
The phylogeny of Anguillicola crassus and A. globiceps based on partial 18S ribosomal RNA sequences
11 Department of Marine Science and Resources, College of Bioresource Sciences, Nihon University, Kameino Fujisawa, Japan2 Department of Aquatic Biosciences, Tokyo University of Fisheries, Minato, Tokyo, Japan.
Abstract:
The parasitic nematodes Anguillicola crassus and A. globiceps infect the swimbladder of eels. To investigate the relationship of these species at the molecular level, the small subunit ribosomal RNA (18S rRNA) genes of A. crassus and A. globiceps were cloned and their nucleotide sequences determined. The 18S rRNA gene of A. crassus and A. globiceps were found to have similar lengths (886 and 888 base pairs, respectively) and demonstrated extensive similarity in their nucleotide sequences, showing 98.8% homology. However, the sequence homology of the 18S rRNA gene of A. crassus with that of other nematodes was found to be in the range of 72.7-89.0% homology, whilst that of A. globiceps was in the range of 73.1-89.4% homology. A phylogenetic reconstruction showed A. crassus to be closely related to A. globiceps. The analysis of nucleotide sequences of the 18S rRNA gene of fish parasites has proven useful in supporting species status and phylogenetic relationships.
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