Biology subjects

Arico, D. S.

Publications and source records attributed to Arico, D. S..

3 recordsLinked to original sources

bioRxiv2025

Multi-Omics Meta-Analysis Provides Insights into Reversible Phosphorylation During Arabidopsis Skotomorphogenesis

We developed a pipeline to standardize and integrate publicly available transcriptomic, proteomic, and phosphoproteomic datasets from Arabidopsis thaliana etiolated seedlings. The pipeline is broadly adaptable, as its database schema and processing scripts can be applied to datasets from any organism or experimental condition. We applied it to etiolated seedlings to uncover protein kinases and protein phosphatases relevant to early skotomorphogenic development, a stage in which seedlings grow underground and rely on precisely regulated signaling networks to ensure survival and successful emergence. This multi-omics approach revealed a comprehensive landscape of protein expression at this developmental stage; however, we observed widespread discrepancies between transcript and protein abundance, pointing to post-transcriptional and/or post-translational regulation. This cross-study minimizes experimental bias and allows the detection of phosphorylation events that may have been overlooked in single-condition studies. A search of kinase specific motifs revealed that RxxS motifs were significantly enriched among phosphorylated peptides in protein phosphatases and microtubule-associated proteins, suggesting regulation by calcium dependent protein kinases (CPKs). CPK3 and CPK9 were identified as the most relevant isoforms in the proteome and phosphokinome, supporting their central role in skotomorphogenesis. Our results underscore the importance of phosphorylation-mediated signaling in coordinating early seedling development and provide a resource for dissecting regulatory networks and candidate genes involved in skotomorphogenesis.

plant biology↗

bioRxiv2025

A molecular glue: LecRKI.9 creates stiff plasma membrane cell wall connections

Water stress challenges plasma membrane - wall attachment. When plants are exposed to strong hyperosmotic stress, water exits the cell leading to plasmolysis, where the plasma membrane detaches partially from the cell wall and reveals discrete and persistent attachment sites in the form of Hechtian strands. Although these structures have been observed in several species for more than a century, the molecular bases behind plasma membrane - wall attachment remains elusive. Through a screen of candidate proteins, we reveal that the overexpression of two lectin receptor-like proteins (LecRK-I.9 and LecTM) increases the density of plasma membrane - wall connections in N. Benthamiana. The extracellular lectin domain of LecRK-I.9 was able to remain in the wall during plasmolysis. Conversely, deletion of the lectin domain in the LecRK-I.9 overexpressor restored the density of Hechtian strands to WT levels. In Arabidopsis, upon hyperosmotic stress, LecRK-I.9 formed largely immobile clusters, whereas lectin-deleted versions of LecRK-I.9 clusters were mobile. Cluster density correlated with predicted tensile stress levels and mechanical reinforcement in the wall before plasmolysis, consistent with a scenario in which attachment of the lectin domain also reflects the wall properties. Last, while overexpressing LecRK-I.9 conferred resistance to low water potential conditions, deletion of the lectin domain in the LecRK-I.9 overexpressor restored a WT response to water stress. Altogether, this demonstrates that the lectin domain of LecRK-I.9 creates persistent plasma membrane - wall attachment sites, with physiological relevance for plant resistance to water stress. SIGNIFICANCE STATEMENTAs observed since the mid-19th century, when placed in hyperosmotic conditions, plant cells undergo plasmolysis and form thin membraneous threads called Hechtian strands. These structures reflect the presence of persistent plasma membrane - cell wall attachment sites. Yet, the molecular components behind these sites are unknown. Through a candidate screen approach, we identify and demonstrate that the lectin domain of a receptor-like kinase provides such molecular glue. We also show that the clustering of the receptor is patterned and correlate with mechanically reinforced cell walls. Conversely, we find that the promotion of attachment increases resistance to water stress. This work revisits an old plant cell biology classic, and opens new avenues of research for plant adaptation to their environment.

plant biology↗

bioRxiv2023

RADIP LIGHT-INDUCED PHOSPHORYLATION CHANGES IN MICROTUBULE RELATED PROTEINS IN ARABIDOPSIS

Rapid hypocotyl elongation allows buried seedlings to reach the surface, where light triggers de-etiolation and inhibits hypocotyl growth mainly by phytochromes A, B and cryptochromes 1, 2. Dynamic phosphorylation/dephosphorylation events provide a mechanism to rapidly transduce light signals. Only recently we have begun to uncover the earliest phospho-signaling responders to light. Here, we report a large-scale phosphoproteomic analysis and identify 20 proteins that change their phosphorylation pattern after 20 min of white light pulse compared to darkness. Microtubule-associated proteins (MAPs) were highly overrepresented in this group. Among them, we studied CIP7 (COP1-INTERACTING-PROTEIN-7), which presented microtubule (MT) localization, in contrast to what was previously described. Phosphorylated isoform in Serine 915 (Sp915) of CIP7 was detected in etiolated seedlings but undetectable after a light pulse in the presence of photoreceptors, while its expression decays with long light exposure. The short hypocotyl phenotype and rearrangement of MTs in etiolated cip7 mutants are complemented by CIP7-YFP and the phospho-mimetic CIP7S915D-YFP, but not the phospho-null CIP7S915A-YFP suggesting that Sp915CIP7 is the active isoform that promotes hypocotyl elongation thorough MT reorganisation in darkness. Our results reveal that the small repertory of proteins that changes the phosphorylation status after a rapid light signal is tightly focused on MAPs; suggesting that phospho-regulation of microtubule-base processes are early targets during de-etiolation. The evidence on Sp915CIP7 supports this idea.

plant biology↗