Project description:We applied Illumina sequencing to identify microRNAs (miRNAs) and piwi-interacting small RNAs (piRNAs) in Dugesia japonica. Dugesia were cut up after seven day’s starvation. DJ1 is the whole Dugesia body, DJ2 is the head part, DJ3 is the tail part, DJ4 is the left part and DJ5 is the right part. Total RNA was extracted by Trizol, and preserved in ethanol, stored at -80°C until further use.
Project description:We applied Illumina sequencing to identify microRNAs (miRNAs) and piwi-interacting small RNAs (piRNAs) in Dugesia japonica. Dugesia were cut up after seven day’s starvation. DJ1 is the whole Dugesia body, DJ2 is the head part, DJ3 is the tail part, DJ4 is the left part and DJ5 is the right part. Total RNA was extracted by Trizol, and preserved in ethanol, stored at -80°C until further use. 5 samples examined?DJ1,DJ2,DJ3,DJ4,DJ5. SRA study (not submitted by GEO): SRP017693
Project description:We report RNA-seq results from planarians of Dugesia japonica species which have developed resistance to a S-adenosyl homocysteine hydrolase inhibitor AdOx after prolonged exposure.
Project description:We employed RNA-sequencing with surgically resected planaria and cysteinyl-specialized pro-resolving mediators (cys-SPMs), including MCTR3, PCTR3 and RCTR3 to identify genes and pathways activated by cys-SPMs.
Project description:Excretory organs contain epithelial cells that form a filtration membrane specialized for ultrafiltration to produce primary urine. In vertebrates, the filtration membrane is made up of slit diaphragm (SD) formed by glomerular podocytes. Basal metazoans such as flatworms are also known have filtration epithelial cells, called flame cells, which exhibit SD-like structures. The molecular components of podocyte SD have been studied in detail, while those of the SD-like structures in basal metazoans including flatworms remain to be clarified. To determine whether the SD-like structures in flatworms have molecular components common to the SD in vertebrate podocytes, we examined the expression of gene homologue for mammalian nephrin, which encodes an essential transmembrane protein that participates in the formation of the SD, in a species of flatworms, planarian (Dugesia japonica). Flame cells were distributed throughout the entire body of the planarian, but the nephrin-expressing cells identified by in situ hybridization were mainly detected at body periphery excluding head region. The distribution pattern of nephrin-expressing cells was similar to that of proliferating cell nuclear antigen-expressing neoblasts, which are pluripotent stem cells characteristic to planarians. These findings indicated that the SD-like structures can be formed without the Nephrin protein in planarian flame cells.
Project description:BACKGROUND: Planarians are considered to be among the extant animals close to one of the earliest groups of organisms that acquired a central nervous system (CNS) during evolution. Planarians have a bilobed brain with nine lateral branches from which a variety of external signals are projected into different portions of the main lobes. Various interneurons process different signals to regulate behavior and learning/memory. Furthermore, planarians have robust regenerative ability and are attracting attention as a new model organism for the study of regeneration. Here we conducted large-scale EST analysis of the head region of the planarian Dugesia japonica to construct a database of the head-region transcriptome, and then performed comparative analyses among related species. RESULTS: A total of 54,752 high-quality EST reads were obtained from a head library of the planarian Dugesia japonica, and 13,167 unigene sequences were produced by de novo assembly. A new method devised here revealed that proteins related to metabolism and defense mechanisms have high flexibility of amino-acid substitutions within the planarian family. Eight-two CNS-development genes were found in the planarian (cf. C. elegans 3; chicken 129). Comparative analysis revealed that 91% of the planarian CNS-development genes could be mapped onto the schistosome genome, but one-third of these shared genes were not expressed in the schistosome. CONCLUSIONS: We constructed a database that is a useful resource for comparative planarian transcriptome studies. Analysis comparing homologous genes between two planarian species showed that the potential of genes is important for accumulation of amino-acid substitutions. The presence of many CNS-development genes in our database supports the notion that the planarian has a fundamental brain with regard to evolution and development at not only the morphological/functional, but also the genomic, level. In addition, our results indicate that the planarian CNS-development genes already existed before the divergence of planarians and schistosomes from their common ancestor.
Project description:Planarians are the earliest free-living platyhelminthe with triploblastic and bilateral-symmetry. As an integral component of tissue homeostasis and regeneration, remodeling occurs constantly in the general planarian life history. In the present study, we isolate three planarian Dugesia japonica Atg8 genes (Djatg8-1, Djatg8-2, Djatg8-3) that show high sequence similarity with Atg8 from yeast and human. Results from whole-mount in situ hybridization indicate that Djatg8-2 and Djatg8-3 are strongly expressed in blastemas during Dugesia japonica regeneration. Using RNA interference, inhibition of Djatg8-1 gene expression has no obvious effect on planarian morphological changes. Interestingly, downregulation of Djatg8-2 gene expression in planarians results in defects in blastema regeneration and tissue regression. Furthermore, loss of Djatg8-3 expression leads to tissue degradation. Taken together, our results suggest that Djatg8-2 and Djatg8-3 play important roles in planarian remodeling during regeneration.