Biology subjects

Sanchez-Corrionero, A.

Publications and source records attributed to Sanchez-Corrionero, A..

4 recordsLinked to original sources

bioRxiv2025

TGA family of transcription factors are nitric oxide sensors in the root stem cell niche

Plant root development is tightly regulated and depends on the coordination among different cell types located in the root stem cell niche (SCN). A complex network of regulators includes the gasotransmitter nitric oxide (NO) known to inhibit primary root growth, modify root architecture and alter meristem organisation. However, little is known about the molecular targets and the mechanistic insights of this signalling molecule during root SCN homeostasis. Here, genetic, molecular and physiological evidence support that TGA transcription factors of the bZIP family, and specifically PERIANTHIA (PAN), contribute to NO-mediated root stem cell regulation. NO induces reversible S-nitrosylation of PAN, thereby inhibiting its binding to DNA and associated transcriptional activation. In turn, the protein-SNO reductase activity of TRXh5 is able to denitrosylate PAN. This switch on and off mechanism of PAN activation modulates WOX5 expression and quiescent centre activity, which alters columella stem cell maintenance through a NO-dependent mechanism. Different TGA members interact with PAN and are also S-nitrosylated, whose expression in the root SCN together with their accumulated mutations contribute to NO sensing during root apical meristem development. Collectively, these findings reveal a molecular framework where NO controls the ability of PAN to bind to its targets as a master regulator of the root SCN.

plant biology↗

bioRxiv2024

UNVEILING STEM CELL INDUCTION MECHANISMS FROM SPATIOTEMPORAL CELL-TYPE-SPECIFIC GENE REGULATORY NETWORKS IN POSTEMBRYONIC ROOT ORGANOGENSIS

Plants grow continuously by developing new organs, a complex process that requires the formation of specific and functional tissue patterns. Tap root systems, as observed in Arabidopsis thaliana, undergo lateral root formation, a developmental mechanism that necessitates the establishment of stem cell lineages. However, the underlying mechanisms remain poorly understood. We have reconstructed a spatiotemporal cell-type-specific transcriptional map of early lateral root organogenesis in Arabidopsis, profiling single and double fluorescent markers across 8 different cell types in the root stem cell lineage. Employing dynamic Bayesian network inference, based on time-course experiments and developmental time, alongside tree-based methods, we investigated lineage developmental progression and precursor stem-cell specification. Our results reveal a morphogenic cascade of hierarchical interdependent transcription factors driving stem cell initiation, and identify the QC/Endodermis transitioning cells as root stem cell progenitors. The associated formative program involves a profound transcriptomic re-arrangement, which, remarkably, precedes the activation of known stem-cell transcriptional signatures. Our data support a model in which root-stem-cell networks do not initiate stem formation, although various stem cell regulators are involved. Collectively, our study identifies core transcriptional signatures associated with stem cell induction and elucidates the dynamic regulatory mechanism driving early stem cell lineage establishment.

developmental biology↗

bioRxiv2023

GNOM-Dependent Endosomal Recycling Sets the Timing of Founder Cell Specification

1.Lateral root growth occurs from primed xylem pole pericycle cells that can be specified as founder cells, but how these cells acquire the pluripotency state to initiate a root organogenesis program is not fully understood. Here, we find that the EMS 204 mutant is unable to specify founder cells due to a point mutation affecting the C-terminal HDS3 domain of the GNOM protein. We used genetics and cell biology to study the trafficking machinery of xylem pole pericycle cells, cells in which GNOM is primarily associated with recycling endosomes. We found that the lack of the HDS3 domain negatively affects the stability of the GNOM protein within the cells of the xylem pole pericycle and, subsequently, the integrity of the trafficking machinery of these cells. We determined that GNOM is responsible for the recycling of AUX1 toward the plasma membrane at the xylem pole pericycle and impairment of this recycling results in premature accumulation of AUX1 in the vacuole. In this work, we describe a cell type-specific cellular mechanism and the role of a particular domain during lateral root development.

plant biology↗

bioRxiv2019

Stem Cell Activity And Regeneration In Roots Require Non-Cell Autonomous Regulation From The Ground Tissue

Stem cells are central to plant development. During root postembryonic development stem cells generating tissues are patterned in layers around a stem cell organizer or quiescent center (QC). How stem cell lineages are initially patterned is unclear. Here, we describe a role for BLUEJAY (BLJ), JACKDAW (JKD) and SCARECROW (SCR) transcription factors in patterning of cell lineages during growth and in patterning reestablishment during regeneration through regulation of number of QC cells and their regenerative capacities. In blj jkd scr mutants, QC cells are progressively lost which results in loss of tissue layers. Upon laser ablation blj jkd scr is impaired in QC division and specification resulting in severe impairment in pattern regeneration. Beyond direct regulation of QC activity by these transcription factors, reduced levels of SHORT-ROOT (SHR) and of PIN auxin transporters were observed in the vasculature of blj jkd scr, leading to strong reduction in the auxin response in the QC. We narrowed down non-cell-autonomous regulation of vascularly expressed genes in blj jkd scr to C-REPEAT BINDING FACTOR 3 (CBF3). cbf3 mutant shows reduced levels of SHR in the vasculature, and in addition QC disorganization and downregulation of the QC regulator WUSCHEL-RELATED HOMEODOMAIN 5 (WOX5). CBF3 gene is primarily expressed in the ground tissue downstream of BLJ, JKD and SCR, while CBF3 protein may move. Targeted-expression of CBF3 to the ground tissue of blj jkd scr recovers radial patterning and regeneration. We propose that BLJ, JKD and SCR regulate QC-mediated patterning, and that part of this regulation involves CBF3.

developmental biology↗