Biology subjects

Tanurdzic, M.

Publications and source records attributed to Tanurdzic, M..

4 recordsLinked to original sources

bioRxiv2025

Systemic and local regulation of root growth by vascular trehalose 6-phosphate is correlated with re-allocation of primary metabolites between shoots and roots

Trehalose 6-phoshpate (Tre6P) is a key signalling molecule that reflects carbon status and integrates it with developmental decision making. Tre6P has been demonstrated to regulate various developmental processes, including vegetative growth, shoot branching, flowering, and root branching. Here, we investigate how vasculature-derived Tre6P influences root system architecture by expressing heterologous Tre6P synthase (TPS) or Tre6P phosphatase (TPP) specifically in the plant vasculature. Plants with elevated vascular-derived Tre6P levels had smaller root systems, reduced sucrose levels, and lower root metabolite levels, whereas vascular TPP overexpression had the opposite effect. Using reciprocal grafting experiments, we identified shoot-derived vascular Tre6P to be the main driver of these systemic responses. In lines with increased Tre6P in the shoot vasculature, the shoot-to-root metabolite ratios were consistently increased, indicating that Tre6P modulates metabolite allocation and utilization to balance carbon partitioning between shoot and root growth. Our data further suggest that vascular Tre6P contributed to optimizing the carbon-to-nitrogen ratio to support growth and fitness. Besides this systemic function, this study shows that root-derived Tre6P also plays a critical local role in modulating root development. Collectively, our results demonstrate that Tre6P in the vasculature functions both systemically and locally to coordinate metabolic status with root growth and architecture.

plant biology↗

bioRxiv2023

Strigolactone-dependent gene regulation requires chromatin remodeling

Strigolactones (SL) function as plant hormones in control of multiple aspects of plant development. Regulation of gene expression by SL is a critical component of SL function. Immediate early gene regulation by SL remains unexplored due to difficulty in dissecting early from late gene expression responses to SL in whole plants. We used leaf-derived Arabidopsis protoplasts to explore early (5-180 minutes) changes in gene expression induced by SL by employing RNA-seq and ATAC-seq. We discovered over 1500 genes regulated by SL as early as 20 minutes, and up to 3669 genes across the entire time course of the experiment, indicative of rapid, dynamic regulation of gene expression in response to SLs. We identified 1447 regions of changing chromatin accessibility in response to SL that are likely to harbour SL cis-regulatory elements and cognate candidate trans-acting factors regulated early by SL. Importantly, we discovered that this extensive transcriptomic reprogramming requires the SYD-containing SWI/SNF chromatin remodelling complex(es) and regulates other chromatin remodellers. This study therefore provides the first evidence that SL signalling requires regulation of chromatin accessibility, and it identifies previously unknown transcriptional targets of strigolactones. One sentence summaryStrigolactone regulated gene expression reprogramming requires chromatin remodelling by SPLAYED.

plant biology↗

bioRxiv2020

Hormonal regulation of the BRC1-dependent strigolactone transcriptome involved in shoot branching responses

The plant hormone strigolactone (SL) inhibits shoot branching by suppressing the growth of axillary buds. This is thought to occur largely via regulation of the transcription factor BRANCHED1 (BRC1). Here, we clarify the central role of BRC1 and identify additional transcriptional responses by which SL might regulate axillary bud outgrowth in garden pea (Pisum sativum). We used a transcriptomic approach to identify differentially expressed transcripts in pea axillary buds in response to a synthetic SL, rac-GR24. Changes in transcript abundance were confirmed by measuring their response to GR245DS. BRC1 was required for the regulation of over half of the fourteen GR245DS-regulated genes, confirming its role as a mediator of SL transcriptional responses in axillary buds. All, but one, of the BRC1-dependent GR245DS-regulated genes were also regulated by branch-promoting treatments cytokinin (CK) and/or decapitation in an opposing manner to SL. This suggests that SL, CK, and decapitation regulate shoot branching via a common pathway. We used correlational analyses of gene co-expression data to infer a gene regulatory network consisting of nine key co-expression modules correlated with rac-GR24 treatment. Enrichment of GO terms such as cell proliferation, carbohydrate responses, and abscisic acid and jasmonic acid hormone pathways suggest a role for these in SL-mediated inhibition of shoot branching. In summary, we have shown that BRC1 is indeed a key transcriptional regulator of the SL signalling pathway in pea buds as well as a focal point of the SL, CK and decapitation signalling pathways to coordinate shoot branching in pea buds. One Sentence SummaryIdentification of genes that are strigolactone-responsive and BRC1-dependent in pea buds reveals a high degree of overlap among strigolactone, cytokinin and decapitation response pathways.

plant biology↗

bioRxiv2019

Transcriptional dynamics of bread wheat in response to nitrate and phosphate supply reveal functional divergence of genetic factors involved in nitrate and phosphate signaling

Nitrate (N) and phosphate (P) levels are sensed by plant cells and signaled via local and systemic signaling pathways to modulate plant growth and development. Understanding the genetic basis of these signaling mechanisms is key to future improvement of nutrient use efficiency. While major progress has been made in understanding N and P signaling pathways and their interaction in the model plant Arabidopsis, understanding of transcriptional responses to N and P in a major monocot crop wheat is lacking. Therefore, we investigated gene expression dynamics of wheat roots in response to N and/or P provision using RNA-Seq. We found that nitrate presence is the major trigger for most of the transcriptional response to occur within 24 h, however, we also identified a large array of synergistic transcriptional responses to concomitant supply of N and P. Through gene co-expression analysis, we identified gene co-expression modules prominent in nitrate signaling and metabolism in wheat. Importantly, we identified likely instances of functional divergence in major N-responsive transcription factors families HRS1/HHO and TGA of wheat from their rice/Arabidopsis homologues. Our work broadens the understanding of wheat N and P transcriptional responses and aids in prioritizing gene candidates for production of wheat varieties that are efficient in nitrogen usage.

plant biology↗