Biology subjects

Petri, L.

Publications and source records attributed to Petri, L..

3 recordsLinked to original sources

bioRxiv2025

Nutrient enrichment intensifies plant competitive effects, favouring monocultures: a global meta-analysis

Excess nutrient deposition is a major driver of plant diversity loss, but the mechanisms of this loss remain unclear. Diversity loss has been interpreted through the niche dimension hypothesis, yet the mechanistic link via competitive effects remains unresolved. Establishing this link demands a global synthesis of how nutrients alter competitive effects, defined as a species ability to perform better or worse with heterospecific competitors than with conspecifics. Strong competitive effects from heterospecifics relative to conspecifics can lead to decline or exclusion of the focal species, whereas weaker competitive effects indicate niche differentiation that promotes coexistence. We conducted a global meta-analysis of 71 plant competition experiments to quantify how nutrient addition alters competitive effects, using biomass as the performance metric. Nutrient addition intensified competitive effects with heterospecifics by 1.5-fold, as focal species biomass was higher with conspecifics. Responses depended on the initial competitive effect under low nutrients: when effects were weak, nutrient addition increased biomass with conspecifics; when effects were strong, nutrient addition increased biomass with heterospecifics, alleviating competition and potentially countering species loss. Competitive effects were amplified most when higher temperatures occurred in dry quarters, suggesting nutrient additions may exacerbate competition under extreme climate conditions. Understanding these interactive effects of nutrient addition, changing climate, and competition is critical for predicting plant responses to global change in both managed and natural ecosystems. Significance StatementNutrient enrichment from agricultural runoff is a driver of plant diversity loss. While patterns of diversity loss from nutrient additions are clear, the processes driving competitive effects that lead to diversity loss remain uncertain. Our global meta-analysis reveals that multiple nutrient addition intensifies competitive effects favouring monocultures i.e, species accumulating more biomass with conspecifics than heterospecifics. Depending on the initial strength of competitive effects, nutrient addition amplified or alleviated them. Temperature and water availability interact with nutrient addition to amplify competitive asymmetries, likely further shaping species dominance under changing climate. These insights provide the first global-scale evidence of nutrient enrichment effects on plant communities and highlight the need to mitigate compounding impacts of fertilization and climate change on diversity.

ecology↗

bioRxiv2025

Antagonistic and Synergistic Roles of Tomato AFP3 Isoforms in Hormonal Regulation and Development

The ABA INSENSITIVE5 BINDING PROTEIN (AFP) family plays a critical role in abscisic acid (ABA) signaling through interaction with the transcription factor ABI5, impacting seed germination and stress responses. Here, we characterize tomato AFP3, which produces two isoforms: a full-length protein and a shorter microProtein (sAFP3) containing only the C-terminal domain. Functional analyses reveal contrasting roles of these isoforms in development; while AFP3 overexpression accelerates shoot growth but impairs seed germination, both afp3 loss-of-function and sAFP3-expressing mutants (afp3-D) exhibit stunted growth and developmental defects. Transcriptome profiling highlights that AFP3 and sAFP3 differentially regulate hormone-related pathways, including salicylic acid, gibberellic acid, and jasmonic acid metabolism. Proteomic interaction studies demonstrate that AFP3 and sAFP3 physically interact, sharing partners involved in hormone signaling. Hormone quantification confirms that AFP3 modulates multiple phytohormones, with elevated ABA in afp3-D mutants and increased gibberellic acid, jasmonic acid, and salicylic acid in both afp3 and afp3-D mutant backgrounds. Moreover, AFP3 controls flower and fruit development, influencing yield and ripening. Together, these findings identify AFP3 as a key integrator of hormonal crosstalk that coordinates growth, development, and stress responses in tomato. The production of dual AFP3 isoforms through alternative transcription, combined with microProtein-mediated dominant-negative regulation, reveals a sophisticated mechanism for dynamically fine-tuning transcriptional networks. This versatile strategy underscores how plants--and potentially other organisms--achieve precise control over complex signaling pathways.

plant biology↗

bioRxiv2022

The m6A writer FIONA1 methylates the 3'UTR of FLC and controls flowering in Arabidopsis

Adenosine bases of RNA can be transiently modified by the deposition of a methyl-group to form N6-methyladenosine (m6A). This adenosine-methylation is an ancient process and the enzymes involved are evolutionary highly conserved. A genetic screen designed to identified suppressors of late flowering transgenic Arabidopsis plants overexpressing the miP1a microProtein yielded a new allele of the FIONA1 (FIO1) m6A-methyltransferase. To characterize the early flowering phenotype of fio1 mutant plants we employed an integrative approach of mRNA-seq, Nanopore direct RNA-sequencing and meRIP-seq to identify differentially expressed transcripts as well as differentially methylated mRNAs. We provide evidence that FIO1 is the elusive methylase responsible for the 3-end methylation of the FLOWERING LOCUS C (FLC) transcript. Furthermore, our genetic and biochemical data suggest that 3-methylation stabilizes FLC mRNAs and non-methylated FLC is a target for rapid degradation.

plant biology↗