title: Metatranscriptome analysis reveals host-microbiome interactions in traps of carnivorous Genlisea species.
abstract: In the carnivorous plant genus Genlisea a unique lobster pot trapping mechanism supplements nutrition in nutrient-poor habitats. A wide spectrum of microbes frequently occurs in Genlisea's leaf-derived traps without clear relevance for Genlisea carnivory. We sequenced the metatranscriptomes of subterrestrial traps vs. the aerial chlorophyll-containing leaves of G. nigrocaulis and of G. hispidula. Ribosomal RNA assignment revealed soil-borne microbial diversity in Genlisea traps, with 92 genera of 19 phyla present in more than one sample. Microbes from 16 of these phyla including proteobacteria, green algae, amoebozoa, fungi, ciliates and metazoans, contributed additionally short-lived mRNA to the metatranscriptome. Furthermore, transcripts of 438 members of hydrolases (e.g., proteases, phosphatases, lipases), mainly resembling those of metazoans, ciliates and green algae, were found. Compared to aerial leaves, Genlisea traps displayed a transcriptional up-regulation of endogenous NADH oxidases generating reactive oxygen species as well as of acid phosphatases for prey digestion. A leaf-vs.-trap transcriptome comparison reflects that carnivory provides inorganic P- and different forms of N-compounds (ammonium, nitrate, amino acid, oligopeptides) and implies the need to protect trap cells against oxidative stress. The analysis elucidates a complex food web inside the Genlisea traps, and suggests ecological relationships between this plant genus and its entrapped microbiome.
authors.affiliation: Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Germany.
authors.forename: Hieu X
authors.initials: HX
authors.lastname: Cao
authors.affiliation: Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmutzer
authors.affiliation: Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Scholz
authors.affiliation: Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research (MPIPZ) Köln, Germany.
authors.forename: Ales
authors.initials: A
authors.lastname: Pecinka
authors.affiliation: Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Germany ; Faculty of Science and Central European Institute of Technology, Masaryk University Brno, Czech Republic.
authors.forename: Ingo
authors.initials: I
authors.lastname: Schubert
authors.affiliation: Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Germany.
authors.forename: Giang T H
authors.initials: GT
authors.lastname: Vu
keywords: Genlisea; RNA-sequencing; algae commensalism; lobster pot trapping; metatranscriptomics; plant carnivory; plant-microbe interaction; whole-genome gene transcription analysis