Biology subjects

Pierdona, F. G.

Publications and source records attributed to Pierdona, F. G..

3 recordsLinked to original sources

bioRxiv2026

SELF-PRUNING 5G interplays with age and gibberellin pathways downstream of SlCOL1 to orchestrate photoperiodic tomato flowering

Tomato (Solanum lycopersicum) is classified as a day-neutral plant, whereas its wild relatives exhibit delayed flowering under long day (LD) conditions due to higher activity of the SELF-PRUNING 5G (SP5G). In Arabidopsis thaliana, CONSTANS (CO) activates FLOWERING LOCUS T (FT), a homolog of SP5G, but whether and how CO integrates with SP5G in tomato flowering was unclear. Here, we demonstrate that SlCOL1 (the tomato CO homolog) delays flowering by directly activating SP5G in a PHYTOCHROME B1 (PHYB1)-dependent manner. Importantly, genetic and molecular analyses combining a photoperiod-responsive tomato line carrying the wild SP5G allele from S. pennellii, together with SlCOL1 and flowering-pathway mutants, revealed synergistic crosstalk among the photoperiodic SlCOL1-SP5G module, age-dependent pathway (mediated mainly by the microRNA156-SlSBP module), gibberellin (GA) pathway, and SINGLE FLOWER TRUSS (SFT) pathway. Mechanistically, we show that SP5G forms a complex with miR156-targeted SlSBP13 to directly regulate SFT expression, and that GA may interfere with SP5G activity. Together, these findings revealed a coordinated network that integrates multiple flowering signals to modulate both shared and pathway-specific targets. Our findings provide a significant advance in understanding the molecular regulation of tomato flowering and offer promising avenues for breeding strategies optimized for diverse environmental conditions and latitudes.

plant biology↗

bioRxiv2024

The microRNA156/SPL9 module mediates auxin response to facilitate apical hook maintenance in Arabidopsis

Auxin coordinates cell growth by promoting or inhibiting cell expansion during etiolated seedling development, but whether and how microRNA modules participate in this process remains unclear. Here, we show the miRNA156/SQUAMOSA PROMOTER-BINDING-PROTEIN-LIKE9 (miR156/SPL9) module is critical for skotomorphogenesis. Perturbation of the miR156/SPL9 module affected skotomorphogenesis, as the loss of miR156 function or SPL9 de-repression led to shorter hypocotyl, higher hook angle, and delayed hook opening. Opposing phenotypes were observed in dark-grown spl9 and miR156-overexpressing seedlings. Importantly, loss of miR156-dependent SPL9 regulation triggered apical hook formation even under reduced levels of endogenous auxin. miR156-targeted SPL9 arrested cell expansion by repressing small auxin-up RNA19 (SAUR19) gene in a FRUITFULL (FUL)-dependent and independent manner. The conserved miR156/SPL9/15 module also affects skotomorphogenesis in tomato, impacting its successful soil emergence. Our findings unravel how the miR156/SPL9 module plays a pivotal role in the auxin network coordinating apical hook development to enable appropriate seedling emergence.

plant biology↗

bioRxiv2024

Age-dependent miR156-targeted SPLs are required for extrafloral nectary development in Passiflora spp.

- Passion flower extrafloral nectaries (EFNs) protrude from adult leaves and facilitate mutualistic interactions with insects, but how age cues control EFN establishment remains poorly understood. - Here, we combined genetic and molecular studies to investigate how leaf development and EFN patterning are regulated through the age-dependent miR156-SQUAMOSA PROMOTER BINDING PROTEIN LIKE (SPL) module in two EFN-containing Passiflora species with distinct leaf shapes. - Low levels of miR156 correlate with leaf maturation and EFN formation in Passiflora edulis and P. cincinnata. Consistently, overexpression of miR156 (miR156-OE), which leads to low levels of SPLs, affected leaf ontogeny and EFN development in both species. Laminar EFNs were underdeveloped and less abundant in both P. edulis and P. cincinnata miR156-OE leaves. Importantly, the ecological relationships established by EFNs and their sugar profiles were negatively regulated by high levels of miR156. Moreover, transcriptome analysis of young leaf primordia revealed that miR156-targeted SPLs may be required for proper expression of leaf and EFN development- associated genes in P. edulis and P. cincinnata. - Our work provides the first evidence that the highly conserved miR156/SPL module regulates EFN development in an age-dependent manner and that the program responsible for EFN development is closely associated with the heteroblastic developmental program of the EFN-bearing leaves.

plant biology↗