Transcriptome dynamics in the asexual cycle of the chordate Botryllus schlosseri. (December 2016)

• Record Type: Journal Article
• Authors: Campagna, Davide; Gasparini, Fabio; Franchi, Nicola; Vitulo, Nicola; Ballin, Francesca; Manni, Lucia; Valle, Giorgio; Ballarin, Loriano
• Is Part Of: BMC genomics. Volume 17:Number 1(2016)
• Page Start: 1
• Page End: 17
• Publication Date: 2016-12
• Subjects: Ascidian -- Apoptosis -- Blastogenesis -- Differentially expressed genes -- RNAseq -- Tunicata; Genomes -- Periodicals; Gene mapping -- Periodicals; Genomics -- Periodicals; Base Sequence -- Periodicals; Chromosome Mapping -- Periodicals; Genetic Techniques -- Periodicals; Sequence Analysis, DNA -- Periodicals; 572.8605
• DOI: 10.1186/s12864-016-2598-1
• Languages: English
• ISSNs: 1471-2164

Abstract

Abstract Background We performed an analysis of the transcriptome during the blastogenesis of the chordateBotryllus schlosseri, focusing in particular on genes involved in cell death by apoptosis. The tunicateB. schlosseri is an ascidian forming colonies characterized by the coexistence of three blastogenetic generations: filter-feeding adults, buds on adults, and budlets on buds. Cyclically, adult tissues undergo apoptosis and are progressively resorbed and replaced by their buds originated by asexual reproduction. This is a feature of colonial tunicates, the only known chordates that can reproduce asexually. Results Thanks to a newly developed web-based platform (http://botryllus.cribi.unipd.it ), we compared the transcriptomes of the mid-cycle, the pre-take-over, and the take-over phases of the colonial blastogenetic cycle. The platform is equipped with programs for comparative analysis and allows to select the statistical stringency. We enriched the genome annotation with 11, 337 new genes; 581 transcripts were resolved as complete open reading frames, translatedin silico into amino acid sequences and then aligned onto the non-redundant sequence database. Significant differentially expressed genes were classified within the gene ontology categories. Among them, we recognized genes involved in apoptosis activation, de-activation, and regulation. Conclusions With the current work, we contributed to the improvement of the first releasedB. schlosseri genome assembly and offer an overview of the transcriptome changes during the blastogenetic cycle, showing up- and down-regulated genes. These results are important for the comprehension of the events underlying colony growth and regression, cell proliferation, colony homeostasis, and competition among different generations.