Casandra Hdez-Reyes

AM fungi challenge a core assumption of cell biology. They can lose a core DNA polymerase (Polɛ) and survive for 360 million years! This blew my mind this weekend!
Reductive evolution of the DNA replication machinery in endosymbiotic fungi | bioRxiv
www.biorxiv.org/content/10.1...

Editing and synthetic applications of chloroplast genomes Chloroplast genetic engineering holds significant strategic importance in the frontier fields of crop genetic improvement and synthetic biology. This article systematically reviews the research progre...

Editing and synthetic applications of chloroplast genomes: Plant Communications www.cell.com/plant-commun... @mplantpcom.bsky.social

Rhizoid‐mediated phosphate uptake and internal transport in the non‐vascular plant Marchantia polymorpha Click on the article title to read more.

Rhizoid‐mediated phosphate uptake and internal transport in the non‐vascular plant Marchantia polymorpha nph.onlinelibrary.wiley.com/doi/full/10....

Optical sections of EdU-labelled Medicago truncatula root nodule primordia 7-days post inoculation imaged under a confocal microscope. Images by Ella Greensmith.

The method published in STAR Protocols, developed by Dr Schiessl and lab members Georgina Wickens and Ella Greensmith, combines highly controlled rhizobial spot inoculation with advanced deep-tissue imaging, enabling researchers to determine exactly where and when nodules form along the root.

Post-replicative chromatin accessibility predicts cell fate change Knudsen and colleagues use repli-ATAC-seq to compare replicated and unreplicated chromatin in two models of cell identity change. They find that lineage-specific elements are accessible earlier in rep...

DNA replication globally disrupts the epigenome. But does this create a chromatin-access opportunity for TF binding to facilitate cell identity change? Now 𝐫𝐞𝐩𝐥𝐢-𝐀𝐓𝐀𝐂-𝐬𝐞𝐪 shows 𝘥𝘦 𝘯𝘰𝘷𝘰 chromatin opening & TF binding occurs specifically post-replication, in cellular differentiation & reprogramming!

Structure-guided discovery of protein functions in plants Protein structure-based searches enable the functional annotation of many plant proteins for which sequence-based methods fall short.

BREAKTHROUGH REPORT: Structure-guided discovery of protein functions in plants (Jiarong Chen , Yanlei Feng , Yuchan Zhang , Jucan Gao , et al) doi.org/10.1093/plce... #PlantScience @aspbofficial

Berlin friends! Come to my talk this Friday if you're interested in mechanisms of cellular plasticity.

Inducing novel endosymbioses by implanting bacteria in fungi - Nature A study presents an approach to establish and track a new endosymbiotic partnership by implanting bacteria in a non-host fungus and shows that stable inheritance of the implanted bacteria is possible ...

Vorholt Lab re-created endosymbiosis in the lab: injected bacteria into a fungus and evolved a heritable partnership.

Evolution, fast-forwarded.

doi.org/10.1038/s415...

PhD opening
Join a collaborative, interdisciplinary project the Excellence Cluster Future Forests @uni-freiburg.de, working on CRISPR/Cas in poplar to understand how trees cope with climate stress.
Apply here: uni-freiburg.de/en/job/00004...
@dompsfr.bsky.social @biologyunifreiburg.bsky.social

New preprint! The same TFs can drive distinct regulatory programs depending on where they bind.

TSS → rapid stress responses

Intronic & upstream → cell-type programs

Enhancer-like CRMs → embryo/meristem programs

Coding-sequence binding → repression
www.biorxiv.org/content/10.6...

Fig. 1.Core structure of plasmodesmata (PDs) and movement routes through PDs. (A) Core structure of the PDs. CW, cell wall (yellow); ER, endoplasmic reticulum membrane (orange); LM, lumenal space of desmotubule (sky blue); PM, plasma membrane (orange); TE, tethering element (reddish purple). (B) Top: enlarged view of the structure depicted in (A); bottom: perpendicular view of the base of the enlarged structure; bluish green diamond, substance translocating along the PM route; vermillion polygon, substance translocating within the cytoplasmic sleeve; blue trapezoid, substance translocating along the ER membrane route; black star, substance translocating within the lumenal route. Bidirectional dashed arrows indicate potential directions of movement for translocating substances of the same color. Colors were selected according to the colorblind-friendly scheme presented in the JFly color tool (University of Cologne; https://jfly.uni-koeln.de/color/) to enhance visual accessibility.

🌿🧭 SPECIAL ISSUE REVIEW 🧭🌿

Linh & Ueda present an in-depth investigation of the potential pathways - at the suborganelle level - provided by plasmodesmata for auxin signal movement in leaf vein patterning.

🔗 doi.org/10.1093/jxb/...

#PlantScience 🧪

Does the noncoding genome actually carry more genetic information than coding seqs? Motivated by this question we mutated every bp in the 10kb MYC locus. Results are even more exciting: Decoding the MYC locus reveals a druggable ultraconserved RNA element www.biorxiv.org/content/10.6...

Outstanding paper on a type 3 effector in rhizobium-legume symbiosis. A must-read! -> Rhizobial effector NopM mediates the ubiquitination of the Nod factor receptor NFR5 and promotes rhizobial symbiosis in Lotus japonicus

very interesting

BIG FIGHT AT POLAND’S WROCLAW ZOO!!!

A Solanoeclepin A precursor functions as a new rhizosphere signaling molecule recruiting growth-promoting microbes under nitrogen deficiency https://www.biorxiv.org/content/10.64898/2025.12.29.696744v1

Box 1 (shortened, full legend in paper): Key developments in elucidating hierarchical chromatin organizations in plants. Chromosome territories Each chromosome occupies a distinct territory within the nucleus, as evidenced by strong intra-chromosomal contacts in a Hi-C contact map. Large A/B compartments Each chromosome is partitioned into large A and B compartments. The heterochromatic B compartment is usually located near the nuclear membrane, whereas the euchromatic A compartment tends to be positioned toward the inner regions of the nucleus. TAD-like domains and compartment domains Large A and B compartments can be further partitioned into TAD-like domains and/or compartment domains.

🧬 SPECIAL ISSUE REVIEW 🧬

In this review, Lee & Seo highlight the hierarchical organization of plant genomes, emphasizing recent advances in understanding local chromatin structures shaped by cohesins and gene borders as fundamental structural units.

🔗 doi.org/10.1093/jxb/...

#PlantScience 🧪

Irma's @irmusjay.bsky.social paper is under the Christmas tree 'in press': Nuclear Myosin VI cooperates with actin to promote transcriptional cluster formation at androgen receptors doi: doi.org/10.1016/j.jb... including SIM imaging of myosin IV with actin on androgen receptors and RNA-Pol2

Symbiosome functionality in Medicago truncatula nodules requires continuous clearing of pectins from the symbiosome space  Central to the legume–rhizobium symbiosis is the formation of organelle-like symbiosomes where nitrogen-fixing bacteroids are enclosed by a host-derived symbiosome membrane. This creates the symbiosome space, which topologically resembles an apoplastic compartment within the cell. While the apoplast of plant cells is largely occupied by the cell wall, symbiosomes are devoid of cell wall polymers. Here, we describe a mechanism that functions to protect and maintain effective nitrogen fixation through the action of cell-wall-degrading enzymes that prevent accumulation of un-esterified pectin within symbiosomes. We identify two symbiotically-induced polygalacturonase (PG) genes in Medicago truncatula, SyPG1 and SyPG2, that are secreted into the symbiosome space. Silencing the expression of SyPG1/2 or editing SyPG1/2 via CRISPR-Cas9 both lead to nodule senescence and trigger excessive accumulation of un-esterified pectin in symbiosome containing cells. Additionally, we show that un-esterified pectins inhibit rhizobial growth both in vivo and in vitro. Together, our results provide evidence for a host-controlled cell wall clearance mechanism that is essential for symbiosome maintenance.

I wasn't expecting that, but it makes total sense. Very cool paper! -> Symbiosome functionality in Medicago truncatula nodules requires continuous clearing of pectins from the symbiosome space | Nature Communications

easy for me 🤭🤭 piñatas originally come from México 🇲🇽 The star-shaped piñata represents the Star of Bethlehem. It also symbolizes the seven deadly sins and that when you break the piñata, it means that you put an end to those sins. We break them during the pre-Christmas parties called “Posadas”

Game changer for cell-based plant genetics: the labs of Caixia Gao & Jin-Long Qiu have developed very efficient self-replicating vectors and they just published a very nice proof-of-concept paper.
#plantscience
www.science.org/doi/10.1126/...

New method paper:
Bennie Lemmens et al @scilifelab.se describe 3D-SPARK, a super-resolution microscopy method that maps changes in DNA replication nanostructures in response to genetic perturbations or drugs, linking spatial cell biology with DNA synthesis dynamics
www.embopress.org/doi/full/10....

Nuclear rupture in confined cell migration triggers nuclear actin polymerization to limit chromatin leakage
DDR sensor ATR protects against nuclear envelope rupture via formin phosphorylation inducing F-actin formation
Christos Kamaras et al @grosselab.bsky.social
www.embopress.org/doi/full/10....

Regulation of YAP activity by nuclear G-actin binding The Yes-associated protein YAP belongs to the TEAD (TEA/ATTS domain) transcriptional co-activators that shuttle between cytoplasm and nuclear compartment. YAP and its paralog TAZ (transcriptional co-a...

Hi all, check out our new preprint where we uncover:"Regulation of YAP activity by nuclear G-actin binding", www.biorxiv.org/cgi/content/...
#actin #YAP/TAZ #transcription #nucleus with help from Sonja-Verena Albers
‪@archaellum.bsky.social‬

Regulation of glucosylceramide synthase and sphingolipid remodeling in the plant response to phosphate deficiency (Bao Yang , Yan Peng , Guo Zhang , Ruifan Liu , Simin Hao , Yi Ren , Shaoping Lu , Xuemin Wang , Liang Guo) doi.org/10.1093/plce... #PlantScience

Fig. 7.Proposed model for the role of DNA methylation (DNAme) in the regulation of hypocotyl elongation during thermomorphogenesis in Arabidopsis. DNAme represses expression of SDC to prevent degradation of PIF4, probably by promoting GA-mediated inhibition of DELLA, thereby enhancing warm-induced auxin biosynthesis and hypocotyl growth. In addition, repression of SDC affects other aspects of auxin metabolism in a PIF4-independent manner (dashed orange line). Besides SDC repression, DNAme might also influence additional regulatory pathways to promote temperature-induced hypocotyl growth (dashed gray and black lines).

☀️ SPECIAL ISSUE RESEARCH 🌡️

📖 Garro et al. show that non-CG DNA methylation represses SDC expression to regulate auxin & gibberellin-related genes, maintaining hypocotyl elongation in warm temps.

🔗 doi.org/10.1093/jxb/...

@maigarro.bsky.social‬ @maticapella.bsky.social‬
#PlantScience 🧪

🤩 BEAUTIFULL highlight of our work by Sabine Muller now published in @currentbiology.bsky.social

👇
doi.org/10.1016/j.cu...

YAP maintains the dynamics of TDP-43 condensates and antagonizes TDP-43 pathological aggregates - Nature Cell Biology Zhang et al. show that YAP binds to TDP-43 to promote TDP-43 multimerization and phase separation. YAP and TDP-43 may co-localize in multiple cell types in oxidative stress and in brain samples from i...

www.nature.com/articles/s41...

Nice auditorium ☀️🌿🌳

The rice AT-rich pincer-like element family of conserved noncoding sequences regulates chromatin loop formation (Yonghan Xu , Dechuan Wu , Manman Zhao , Wei Tang , Xiang Cheng , Qunwen Hu , Zhiwei Liu , Jiangtao Gan , et al) doi.org/10.1093/plph... #PlantScience