New Phytologist最新文献

The New Phytologist Foundation is delighted to announce that Professor Maarja Öpik will take up the position of Editor-in-Chief of New Phytologist from January 2025, for an initial term of 5 years.

Maarja has served as a member of New Phytologist's editorial board since 2013 and is a professor of Molecular Ecology and Director of the Institute of Ecology and Earth Sciences at the Faculty of Science and Technology at the University of Tartu, Estonia.

Maarja's research addresses the interactions between plants and mycorrhizal fungi, with specific focus on arbuscular mycorrhizal fungal diversity patterns. Maarja pioneered one of the first public databases in the field, MaarjAM (Öpik et al., 2010), which is now widely used as a tool for arbuscular mycorrhizal fungal identification and in arbuscular mycorrhizal fungus ecological research.

Maarja will lead an outstanding international board of Editors that focuses on all aspects of plant biology, spanning the journal's five sections: Physiology & Development, Interaction, Environment, Evolution, and Transformative Plant Biotechnology. Maarja noted ‘New Phytologist is a journal that inspires its readers and authors, and this is the main quality that I aspire to keep, strengthen and develop as an Editor-in-Chief. Publishing inspiring papers and maintaining an active, engaging scientific community contributes towards strengthening the journal and its community’.

Maarja will take over the position from Professor Alistair M. Hetherington, who will step down as Editor-in-Chief after 12 years of outstanding service. We are grateful for the outstanding leadership offered by Alistair Hetherington, and the journal's achievements under his tenure as Editor-in-Chief are many. As we look forward, I am delighted to welcome Maarja, an exemplary scientist and editorial colleague to the position of Editor-in-Chief. We are excited to support Maarja's vision for the journal, and her commitment to the ethos of the Foundation in promoting plant science and supporting the international community of plant biologists. We look forward to the next chapter of the journal's development under Maarja's leadership.

The New Phytologist Foundation remains neutral with regard to jurisdictional claims in maps and in any institutional affiliations.

• Carbon reserves are distributed throughout plant cells allowing past photosynthesis to fuel current metabolism. In trees, comparing the radiocarbon (Δ¹⁴C) of reserves to the atmospheric bomb spike can trace reserve ages.
• We synthesized Δ¹⁴C observations of stem reserves in nine tree species, fitting a new process model of reserve building. We asked how the distribution, mixing, and turnover of reserves vary across trees and species. We also explored how stress (drought and aridity) and disturbance (fire and bark beetles) perturb reserves.
• Given sufficient sapwood, young (< 1 yr) and old (20–60+ yr) reserves were simultaneously present in single trees, including ‘prebomb’ reserves in two conifers. The process model suggested that most reserves are deeply mixed (30.2 ± 21.7 rings) and then respired (2.7 ± 3.5-yr turnover time). Disturbance strongly increased Δ¹⁴C mean ages of reserves (+15–35 yr), while drought and aridity effects on mixing and turnover were species-dependent. Fire recovery in Sequoia sempervirens also appears to involve previously unobserved outward mixing of old reserves.
• Deep mixing and rapid turnover indicate most photosynthate is rapidly metabolized. Yet ecological variation in reserve ages is enormous, perhaps driven by stress and disturbance. Across species, maximum reserve ages appear primarily constrained by sapwood longevity, and thus old reserves are probably widespread.

• Soil salinization is a major factor limiting the sustainable development of the grape industry. Circular RNAs (circRNAs) are more stable than linear mRNAs and are involved in stress responses. However, the biological functions and molecular mechanisms underlying antisense circRNAs in plants remain unclear.
• We identified the antisense circRNA VvcircABH through high-throughput sequencing. Using genetic transformation methods and molecular biological techniques, we analyzed the effects of VvcircABH on the response to salt stress and the mechanisms underlying its effects.
• VvcircABH was located in the nucleus and upregulated by salt stress, while the expression level of its cognate gene VvABH (alpha/beta-hydrolase) was downregulated. VvcircABH overexpression or VvABH silencing greatly enhanced grape salt tolerance. VvcircABH could bind to the overlapping region and inhibits VvABH pre-mRNA splicing, thereby decreasing the expression level of VvABH. Additionally, VvcircABH repressed the additive effect of VvABH on the interaction between VvBRI1 (brassinosteroid-insensitive 1) and VvBKI1 (BRI1 kinase inhibitor 1), thus influencing the plant's response to BR, which plays important roles in plant salt tolerance.
• We conclude that VvcircABH and VvABH play distinct roles in the salt tolerance and brassinosteroid signaling response, and VvcircABH could govern the expression of VvABH by inhibiting its splicing.

• Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) exhibits catalytic promiscuity, resulting in error-prone reactions and the formation of inhibitory sugar phosphates. Specifically, Xylulose-1,5-bisphosphate (XuBP) acts as an inhibitor by binding to the active site of Rubisco, thereby impairing its catalytic function. Thermolabile Rubisco activase (Rca) facilitates the release of such inhibitors, including XuBP, by remodelling Rubisco. In Arabidopsis thaliana, the phosphatase pair CbbYA and CbbYB subsequently hydrolyses XuBP to prevent its rebinding to Rubisco.
• To explore the functional interplay between these components in maintaining photosynthesis, cbbya, cbbyb and cbbyab mutants were crossed with RCA knockdown (rca-2) lines. Additionally, both RCA and CBBYA were overexpressed in wild-type (WT) Arabidopsis thaliana.
• Phenotypic analyses revealed an exacerbation in decreased growth and photosynthetic efficiency in the cbbyab rca-2 double mutants compared with the control mutants (cbbyab and rca-2), indicating a negative genetic interaction. Furthermore, the co-overexpression of RCA and CBBYA did not improve photosynthesis under short-term heat stress, and light reactions were adversely affected relative to the WT.
• These findings illustrate the synergistic roles of Rca, CbbYA and CbbYB in maintaining carbon fixation and promoting plant growth in Arabidopsis thaliana. Thus, the coordinated regulation of Rca and CbbY enzymes is crucial for optimizing photosynthetic efficiency.

The flowering plant life cycle is completed by an alternation of diploid and haploid generations. The diploid sporophytes produce initial cells that undergo meiosis and produce spores. From haploid spores, male or female gametophytes, which produce gametes, develop. The union of gametes at fertilization restores diploidy in the zygote that initiates a new cycle of diploid sporophyte development. During this complex process, cell fate determination occurs at each of the critical stages and necessarily underpins successful plant reproduction. Here, we summarize available knowledge on the regulatory mechanism of cell fate determination at these critical stages of sexual reproduction, including sporogenesis, gametogenesis, and early embryogenesis, with particular emphasis on regulatory pathways of both male and female gametes before fertilization, and both apical and basal cell lineages of a proembryo after fertilization. Investigations reveal that cell fate determination involves multiple regulatory factors, such as positional information, differential distribution of cell fate determinants, cell-to-cell communication, and cell type-specific transcription factors. These factors temporally and spatially act for different cell type differentiation to ensure successful sexual reproduction. These new insights into regulatory mechanisms underlying sexual cell fate determination not only updates our knowledge on sexual plant reproduction, but also provides new ideas and tools for crop breeding.