Evidence from Arabidopsis and other systems indicates that CK signaling delays chlorophyll catabolism

The gap

Evidence profile

Sourced from the future work of the source papers, classified as general, drawn from work published between 2025 and 2026, spanning 3 journals. Those papers have been cited 86 times in total.

Supporting evidence — 4 representative gaps

• Comparative Chloroplast Genomics of Sugar Beet and Wild Relatives: Insights into Photosystem Gene Regulation and Stress Tolerance (2026) · Functional & Integrative Genomics · doi

  These findings provide valuable insights for applied breed- ing programs. Identification of SNP differences and varia- tions within promoter regions of PSI and PSII genes may be particularly relevant for studies on climate resilience. Although gene expression analysis was not performed in the present study, future investigations incorporating in-depth molecular analyses will be essential to elucidate the regula- tory effects of SNPs and indels within promoter fragments and their contribution to stress-responsive gene regulation. In conclusion, the promoter regions of chloroplast- encoded photosystem genes in Beta exhibit a highly conserved regulatory architecture characterized by the coordinated presence of PEP and NEP elements. This dual- promoter framework likely ensures robust and flexible tran- scriptional control under varying environmental conditions. While overall sequence conservation reflects strong evo- lutionary constraint, the presence of minor SNPs, particu- larly in B. corolliflora, highlights subtle genetic variation that may contribute to adaptive regulation rather than major functional divergence. Together, these findings suggest that Beta chloroplast promoters are finely tuned to balance transcriptional stabil- ity with limited regulatory plasticity, providing a molecular basis for maintaining photosynthetic efficiency and resil- ience under abiotic stress. These insights offer a foundation for exploiting promoter variation in future breeding strate- gies aimed at improving stress tolerance in sugar beet. Future research should prioritize three key directions to translate these genomic insights into practical applications. Page 15 of 18 98 First, functional validation of identified cis-elements through expression profiling under controlled stress conditions, pro- moter–reporter assays, and transgenic analyses will con- firm their regulatory roles and stress-response mechanisms. Second, the integration of chloroplast genomic insights with advanced gene-editing technologies, such as CRISPR- based promoter modification, offers a promising approach to fine-tune photosystem gene regulation and improve plant performance under climate-induced stress without introduc- ing foreign DNA. Third, expanding chloroplast comparative studies across a wider range of Beta accessions, including underutilized wild populations and landraces, will further elucidate the molecular mechanisms underlying stress resil- ience and uncover additional genetic diversity for breeding. Together, these efforts will guide the development of high- yielding, climate-resilient sugar beet cultivars for sustain- able agriculture in the face of global environmental change. Supplementary Information The online version contains supplementary material available at h t t p s : / / d o i . o r g / 1 0 . 1 0 0 7 / s 1 0 1 4 2 - 0 2 6 - 0 1 8 8 3 - 3 . Acknowledgements Noreen Aslam is thankful to TUBITAK for sup- porting her studies. Mehmet Örgeç was supported by the TÜBİTAK Scientist Support Programs Directorate (BİDEB), 2211-A National PhD Scholarship Program, and The Higher Education Council (YÖK) through 100/2000 Doctoral Scholarship Program. Author contributions Conceptualization: MS, MTW and SG. Method- ology: MS, MTW and MCB. Formal analysis and investigation: MS, Abdullah, NB, IA, MCB, NA, MO, MTW, EG and SG. Writing - origi- nal draft preparation: Abdullah, MS, NA, MTW and SG. Writing - re- view and editing: MS, Abdullah, MTW, MCB, NA, MO, EG and SG. Funding acquisition: SG. Resources: IA, MTW, and SG. Supervision: MTW and SG. Funding This work was supported by Scientific and Technological Re- search Council of Türkiye (TÜBİTAK) (Grant No. KBAG-120O596) to Songul Gurel. Data availability The sequencing data of the sugar beet genotypes were deposited to NCBI under the accession numbers PV151546 PV069735, PV069737, PV069736, PV135462, PV135457, PV135461, PV135459, PV135458, PV135460.

  generalfuture work
  Keywords: stress promoter insights gene chloroplast climate future molecular regulation beta regulatory sugar beet abdullah programs
• Genome evolution through polyploidy: Enhancing plant stress resilience in agriculture (2026) · Proceedings of the National Academy of Sciences · cited 1× · doi

  Polyploidy is now understood to drive significant shifts in gene content and cis-regulatory variation, both of which are fundamental to plant stress resilience. Gene content varia- tion, including the gain or loss of specific genes, directly impacts metabolic and signaling pathways vital for adapting to environmental challenges. Simultaneously, changes in CREs lead to diverse and novel patterns of gene activity that fine-tune stress responses. This dynamic interplay between genetic and regulatory changes contributes to the expanded phenotypic diversity and enhanced adaptive capabilities that enable polyploids to thrive under challenging conditions. A comprehensive understanding of regulatory variation in polyploids holds immense potential for developing next- generation, climate-resilient crops and ensuring global food security. While the added phenotypic diversity, genetic Fig. 4. HE and its impact on gene dosage and structure. This figure illustrates how HEs, which are recombination events between chromosomes from different diploid progenitors (shown in blue and yellow), can alter gene dosage and create novel gene structures in a polyploid genome. Panel (A) depicts the potential outcomes of HE on homoeolog dosage. A newly formed tetraploid begins with two copies from each parental genome (Left). HEs and subsequent segregation can alter this ratio to 3:1 or 1:3 (Middle) and, in extreme cases, to 4:0 or 0:4 (Right). Panel (B) shows that HEs can also occur within a gene. These events can either alter CRE variants associated with a gene (Left to Middle) or, in more extreme cases, create chimeric versions of genes consisting of exons from both homoeologs (Middle to Right). 8 of 10 https://doi.org/10.1073/pnas.2522064123 pnas.org redundancy, and multiple gene variants in polyploids provide a rich substrate for adaptation, they have historically made it difficult to apply molecular breeding approaches. For this reason, some breeding communities have opted to work with diploid progenitors, sacrificing valuable phenotypic diversity for the simplicity and lower cost of genetic markers. The advent of new genotyping and bioinformatic tools, combined with the development of haplotype-phased pangenomes, is making the use of molecular breeding tools with polyploids increasingly more accessible and affordable for a broader range of communities working on a wide variety of poly- ploid crops. While significant progress has been made in understand- ing gene and CRE evolution following polyploidy, many aspects remain poorly understood. It is likely that insights into stress adaptations and resilience are likely to derive from these five key research areas. 1 Dissecting Regulatory Complexes: Understanding which CREs function together to regulate a single gene is a major challenge. Future research could leverage gene and CRE fractionation in

  generalfuture work
  Keywords: gene regulatory polyploids stress genetic phenotypic diversity dosage alter middle breeding polyploidy understood significant content
• Cytokinin availability and chloroplast functional lifetime in senescing leaves (2026) · Frontiers in Plant Science · doi

  Evidence from Arabidopsis and other systems indicates that CK signaling delays chlorophyll catabolism, slows disassembly of pho- tosynthetic complexes, supports chloroplast-related gene expres- sion, and limits ROS-driven acceleration of senescence. The recent observation in detached Arabidopsis leaves that CKs can transiently and reversibly downregulate PSII photochemistry during prolonged darkness adds an important nuance. In such contexts, CK action may protect leaves by lowering electron pressure and improving redox control before later photosynthetic competence is main- tained, indicating that transient photosynthetic down-modulation can be part of the protective response (Krieger‐Liszkay et al., 2019; Domı́nguez and Cejudo, 2021; Kábrtová et al., 2026). Several lines of evidence indicate that CKs actively reprogram the transcriptome of mature leaves and buffer redox-dependent feedbacks associated with photosynthetic decline. By limiting

  generalfuture work
  Keywords: leaves photosynthetic evidence arabidopsis redox systems indicates signaling delays chlorophyll catabolism slows disassembly tosynthetic complexes
• Adaptive responses of plants to light stress: mechanisms of photoprotection and acclimation. A review (2025) · Frontiers in Plant Science · cited 85× · doi

  Plants in their natural habitats face various stresses, including light stress, which can reduce photosynthetic efficiency and vary from brief periods to several months. Effective protection strategies are crucial for their growth, survival, and reproduction. Plants have developed multiple defense mechanisms, such as regulating redox-active molecules, scavenging ROS, decreasing light absorption, and modifying their transcriptome and metabolome. Recent research has shed light on how plants balance efficient light harvesting with protection. They trigger scavenging ROS, adapting chloroplast and stomatal movement as well, and finally synthesizing anthocyanins for downstream machinery to capture more energy while preventing damage. Number-wise, indispensable help comes from plant hormones or physical and small molecules in reducing light stress. Light stress underscores a serious problem for plants, resulting in considerable negative effects such as the inactivation of PSII also termed photoinhibition. In response to this, plants call in to play the two repairing pathways for PSII and NPQ to mitigate any further damages. Furthermore, it enhances the expression of chloroplast proteins that maintain and repair photosystem, preserving high light stress. Although this includes strategies for adaptation, our explanation of the specific assembly steps withing PSII damage, the role of additional auxiliary proteins in photosystem remodeling or quality control, and degradation mechanisms remain largely unknown. Other future studies are necessary to address these missing elements that are involved in the responses of the plants, under high light and low light stresses. Medium level light, while less damaging than fluctuating high lighting levels will still have dramatic effects on many aspects of plant growth and development. State transitions and cyclic electron transport are examples of the mechanisms that plants use to help reduce damage from these changes in light. Over the past decade, research on how plants perceive and respond to changes in light has expanded considerably. Yet our knowledge is based mainly on controlled laboratory systems, meaning we lack a detailed understanding of how plants respond to the fluctuating solar resources they experience in real life. The sources of uncertainty include how plants perceive changes in light intensity, the cellular signaling pathways that mediate communication between the nucleus and organelles (including signals that alter photosynthetic systems to dissipate/rebalance excess excitation energy), as well as plastid-to- nucleus retrograde stress responses. More exploration is required to uncover all of the regulatory processes by which plants can cope with changes in light availability. A better understanding of how plants handle light stress may give insight into ways we could us genetic manipulation to improve photosynthesis. This enables faster assembly or reassembly of photosynthetic machinery in response to changes in light

  generalfuture work
  Keywords: light plants stress changes photosynthetic mechanisms damage psii high stresses including reduce protection strategies growth

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