Biology subjects

Blancaflor, E. B.

Publications and source records attributed to Blancaflor, E. B..

3 recordsLinked to original sources

bioRxiv2024

Integrated GWAS and Transcriptomic Analysis Identify New Candidate Genes for Seminal Root Growth Angle in Wheat (Triticum aestivum L.)

Increased interest in root system architecture (RSA) and its major importance for nutrient and water uptake have intensified the efforts for a detailed study of the different root types within the homorhizic root system found in most monocotyledons as wheat. Mature homorhizic root system comprises two root types regarding their origin: embryonic and pot embryonic. However, knowledge of the different root type ss physiology and RSA plasticity is still limited. In wheat, embryonic roots are the first to develop after seed germination and have an important role in crop establishment. Wheat seedlings develop between 3 and 5 embryonic roots that have the same origin, but they differ in their spatial distribution. The first emerging root of a wheat seedling develops from the base of the embryo and grows vertically down. The rest of the seminal roots emerge from the lateral sides of the embryo and grow with a very specific set-point angle dependent on variety. In this study, we showed that seminal roots with different set-point angle displayed differences in response to gravity and in auxin transport. We hypothesized that the differences in RSA among root types will be directed by differences in their transcriptomic profiles. To that end, we performed an RNA sequencing analysis on both root types. With the aim of gaining a more complete understanding of the seminal root architecture plasticity, we also studied the genetic variability associated with root set-point angle performing a Genome-Wide Association Study in a wheat genetic panel of 200 accessions. Our results combined, uncovered a cluster of genes located in Chromosome 2B that comprises new players in wheat RSA with potential roles in plant response to abiotic stress.

plant biology↗

bioRxiv2023

Glycome profiling and immunohistochemistry uncover spaceflight-induced changes in non-cellulosic cell wall components in Arabidopsis thaliana seedling roots

A large and diverse library of glycan-directed monoclonal antibodies (mAbs) was used to determine if plant cell walls are modified by low-gravity conditions encountered during spaceflight. This method called glycome profiling (glycomics) revealed global differences in non-cellulosic cell wall epitopes in Arabidopsis thaliana root extracts recovered from RNA purification columns between seedlings grown on the International Space Station-based Vegetable Production System and paired ground (1-g) controls. Immunohistochemistry on 11-day-old seedling primary root sections showed that ten of twenty-two mAbs that exhibited spaceflight-induced increases in binding through glycomics, labeled space-grown roots more intensely than those from the ground. The ten mAbs recognized xyloglucan, xylan, and arabinogalactan epitopes. Notably, three xylem-enriched unsubstituted xylan backbone epitopes were more intensely labeled in space-grown roots than in ground-grown roots, suggesting that the spaceflight environment accelerated root secondary cell wall formation. This study highlights the feasibility of glycomics for high-throughput evaluation of cell wall glycans using only root high alkaline extracts from RNA purification columns, and subsequent validation of these results by immunohistochemistry. This approach will benefit plant space biological studies because it extends the analyses possible from the limited amounts of samples returned from spaceflight and help uncover microgravity-induced tissue-specific changes in plant cell walls.

plant biology↗

bioRxiv2020

The BEACH Domain-Containing Protein SPIRRIG Modulates Actin-Dependent Root Hair Development in Coordination with the WAVE/SCAR and ARP2/3 Complexes

Root hairs are single cell protrusions that enable roots to optimize nutrient and water acquisition. They attain their tubular shapes by confining growth to the cell apex, a process called tip growth. The actin cytoskeleton and endomembrane systems are essential for tip growth; however, little is known about how these cellular components coordinate their activities during this process. Here, we show that SPIRRIG (SPI), a BEACH domain-containing protein involved in membrane trafficking, and BRK1 and SCAR2, subunits of the WAVE/SCAR (W/SC) actin nucleating promoting complex, display polarized localizations to root hairs at distinct developmental stages. SPI accumulates at the root hair apex via post-Golgi vesicles and positively regulates tip growth by maintaining tip-focused vesicle secretion and filamentous-actin integrity. BRK1 and SCAR2 on the other hand, mark the root hair initiation domain to specify the position of root hair emergence. Consistent with the localization data, tip growth was reduced in spi and the position of root hair emergence was disrupted in brk1 and scar1234. BRK1 depletion coincided with SPI accumulation as root hairs transitioned from initiation to tip growth. Taken together, our work uncovers a role for SPI in facilitating actin-dependent root hair development through pathways that might intersect with W/SC.

plant biology↗