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Sulli, M.

Publications and source records attributed to Sulli, M..

3 recordsLinked to original sources

Hydroxylated monoterpenes mimic bacterial attack to trigger jasmonate-dependent self-amplifying immunity in tomato

Hydroxylated monoterpenes (HMTPs) are emitted during resistant tomato-Pseudomonas syringae interactions and confer antibacterial resistance, yet their integration into immune signalling remains poorly understood. Here we show that HMTPs act as endogenous mimics of pathogen attack that engage canonical defence pathways in tomato. Using -terpineol as a representative HMTP, we demonstrate that this volatile activates MPK kinase-, calcium- and reactive oxygen species (ROS)-dependent signalling, promotes jasmonate and salicylic acid accumulation, and induces pathogen-like stomatal immunity independently of abscisic acid. Functional analyses revealed that HMTPs biosynthesis depends on ROS and jasmonate signalling, and HMTPs further promote their own accumulation, establishing a self-reinforcing feed-forward mechanism. Moreover, in vitro oxidative conditions drive chemical remodelling and selective interconversion among HMTPs, contributing to volatile diversification and favouring the accumulation of highly bioactive hydroxylated forms. Consistently, deuterium-labelled linalool is incorporated into plant metabolism and converted into deuterated -terpineol in planta, providing direct evidence for volatile interconversion. Together, our findings establish HMTPs as dynamic amplifiers of tomato antibacterial immunity and key actors in pathogen-associated signalling.

plant biology↗

A multi-omic Nicotiana benthamiana resource for fundamental research and biotechnology

Nicotiana benthamiana is an invaluable model plant and biotechnology platform. To further improve its usefulness and versatility, we have produced high quality chromosome level genome assemblies and multi-omic datasets for both the ubiquitously used LAB strain and a distantly related wild accession, QLD, as well as mapping their single nucleotide polymorphisms with two additional laboratory and four additional wild accessions. LAB and QLD have many genetic, functional, and metabolic differences. These coupled with their high inter-fertility and equally efficient transient and stable transformation and genome editing provide a powerful resource partnership. Their [~]3Gb allotetraploid genomes show advanced diploidisation with major chromosome loss and rearrangement, extensive homoeologous gene loss, and widespread segmental allopolyploidy. Recent bursts of Copia mobility, not seen in other Nicotiana genomes, have probably aided N. benthamianas adaptation to a spectrum of Australian ecologies.

plant biology↗

European Vintage tomatoes galore: a result of farmers combinatorial assorting/swapping of a few diversity rich loci

A comprehensive collection of 1,254 tomato accessions corresponding to European heirlooms and landraces, together with modern varieties, early domesticates and wild relatives, were analyzed by genotyping by sequencing. A continuous genetic gradient between the vintage and modern varieties was observed. European vintage tomatoes displayed very low genetic diversity, with only 298 loci out of 64,943 variants being polymorphic at the 95% threshold. European vintage tomatoes could be classified in several genetic groups. Two main clusters consisting of Spanish and Italian accessions showed a higher genetic diversity than the rest varieties, suggesting that these regions might be independent secondary centers of diversity and with a different history. Other varieties seem to be the result of a more recent complex pattern of migrations and hybridizations among the European regions. Several polymorphic loci were associated in a GWAS with fruit morphological traits in the European vintage collection, and the corresponding alleles were found to contribute to the distinctive phenotypic characteristic of the genetic varietal groups. The few highly polymorphic loci associated with morphological traits in an otherwise diversity-poor genome suggests a history of balancing selection, in which tomato farmers maintained the morphological variation by applying a high selective pressure within different varietal types. HighlightThe high phenotypic diversity observed among European vintage varieties was created by traditional farmers by combining very few polymorphic loci subjected to balancing selection.

plant biology↗