@article {1538,
	title = {Unusually Large Number of Mutations in Asexually Reproducing Clonal Planarian <i>Dugesia japonica</i>},
	journal = {PLoS ONE},
	volume = {10},
	year = {2015},
	month = {2015},
	pages = {e0143525},
	publisher = {Public Library of Science},
	address = {San Francisco, CA USA},
	abstract = {<p>We established a laboratory clonal strain of freshwater planarian (Dugesia japonica) that was derived from a single individual and that continued to undergo autotomous asexual reproduction for more than 20 years, and we performed large-scale genome sequencing and transcriptome analysis on it. Despite the fact that a completely clonal strain of the planarian was used, an unusually large number of mutations were detected. To enable quantitative genetic analysis of such a unique organism, we developed a new model called the Reference Gene Model, and used it to conduct large-scale transcriptome analysis. The results revealed large numbers of mutations not only outside but also inside gene-coding regions. Non-synonymous SNPs were detected in 74\% of the genes for which valid ORFs were predicted. Interestingly, the high-mutation genes, such as metabolism- and defense-related genes, were correlated with genes that were previously identified as diverse genes among different planarian species. Although a large number of amino acid substitutions were apparently accumulated during asexual reproduction over this long period of time, the planarian maintained normal body-shape, behaviors, and physiological functions. The results of the present study reveal a unique aspect of asexual reproduction.</p>
},
	isbn = {1932-6203},
	url = {http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4654569/},
	author = {Nishimura, Osamu and Hosoda, Kazutaka and Kawaguchi, Eri and Yazawa, Shigenobu and Hayashi, Tetsutaro and Inoue, Takeshi and Umesono, Yoshihiko and Agata, Kiyokazu},
	editor = {Fu, Binying}
}
