TY - JOUR A1 - Grote, Jessica A1 - Krysciak, Dagmar A1 - Petersen, Katrin A1 - Güllert, Simon A1 - Schmeißer, Christel A1 - Förstner, Konrad Ulrich A1 - Krishnan, Hari B. A1 - Schwalbe, Harald A1 - Kubatova, Nina A1 - Streit, Wolfgang R. T1 - The absence of the N-acyl-homoserine-lactone autoinducer synthase genes traI and ngrI increases the copy number of the symbiotic plasmid in Sinorhizobium fredii NGR234 T2 - Frontiers in microbiology N2 - Plant-released flavonoids induce the transcription of symbiotic genes in rhizobia and one of the first bacterial responses is the synthesis of so called Nod factors. They are responsible for the initial root hair curling during onset of root nodule development. This signal exchange is believed to be essential for initiating the plant symbiosis with rhizobia affiliated with the Alphaproteobacteria. Here, we provide evidence that in the broad host range strain Sinorhizobium fredii NGR234 the complete lack of quorum sensing molecules results in an elevated copy number of its symbiotic plasmid (pNGR234a). This in turn triggers the expression of symbiotic genes and the production of Nod factors in the absence of plant signals. Therefore, increasing the copy number of specific plasmids could be a widespread mechanism of specialized bacterial populations to bridge gaps in signaling cascades. KW - Sinorhizobium fredii KW - plasmid copy number KW - plant symbioses KW - quorum sensing (QS) KW - RNA sequencing (RNA-Seq) Y1 - 2017 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/43683 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-436832 SN - 1664-302X N1 - Copyright © 2016 Grote, Krysciak, Petersen, Güllert, Schmeisser, Förstner, Krishnan, Schwalbe, Kubatova and Streit. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. VL - 7 IS - Art. 1858 SP - 1 EP - 13 PB - Frontiers Media CY - Lausanne ER -