Biology subjects

Garcia-Sogo, B.

Publications and source records attributed to Garcia-Sogo, B..

3 recordsLinked to original sources

bioRxiv2024

A deep dive into the FALSIFLORA contribution to tomato reproductive development through a comprehensive allelic series analysis

Plants undergo continuous growth and development thanks to meristems, specialized groups of pluripotent stem cells that remain in their undifferentiated state throughout the plants life cycle. Meristem transition from the vegetative to the reproductive phase heavily influences plant reproductive success and agricultural productivity. In tomato (Solanum lycopersicum L.), FALSIFLORA (FA), the orthologue of the Arabidopsis LEAFY gene, promotes floral transition by specifying floral meristem identity and regulating the expression of genes responsible for floral organ identity and development. In this study, the allelic series of FA has been expanded by combining the screening of a tomato EMS mutant collection with overexpression, gene silencing and CRISPR/Cas9 genome editing approaches, aimed to deepen the understanding of the functional role of FA during tomato reproductive development. The phenotypic and molecular characterization of the FA allelic series revealed the multifaceted role of FA acting in both early and late stages of floral ontogeny. Thus, in addition to promoting floral transition and specifying floral meristem identity, FA also plays a role in inflorescence meristem maturation and termination, thereby regulating the inflorescence architecture. Furthermore, FA exerts regulatory control over the expression of the tomato homologs of AGAMOUS (TOMATO AGAMOUS1, TAG1) and WUSCHEL (SlWUS), underscoring its function in promoting carpel development and suppressing floral stem cell activity, thereby establishing floral determinacy. In conclusion, our findings demonstrate the potential of employing mutant allelic series as powerful tools for elucidating gene functions and deciphering the intricate molecular basis underlying biological processes. Plain Language SummaryOur research aims to gain a deeper understanding of the role of FALSIFLORA in tomato reproductive development. The FALSIFLORA allelic spectrum was expanded through mutant screening, along with overexpression, silencing, and CRISPR/Cas9 editing approaches. Our findings reveal that FALSIFLORA has a dual function in early and late floral development stages. In addition to promoting floral transition and specifying floral meristem identity, FA regulates the expression of tomato genes homologous to WUSCHEL and AGAMOUS, which play an essential role in stem cell regulation and carpel development. This study highlights the value of allelic series in elucidating gene functions and intricate biological mechanisms.

plant biology↗

bioRxiv2024

The Pivotal Involvement of the Respiratory burst oxidase G (SlRbohG) Gene in H2O2 Production Under Stress for Proper Na+ Homeostasis Regulation in Tomato

Regulation of sodium homeostasis is crucial for plant response to salinity conditions. Here we report on the genetic and physiological characterization of two tomato allelic mutants, sodium gatherer1-2 (sga1-2), which exhibit pronounced chlorosis and hyperhydration under salt stress. Mapping-by-sequencing revealed that mutant phenotype resulted from mutations in the SlRbohG gene, and CRISPR/Cas9 knockouts of this gene gave phenocopies of the sga1-2 mutants. Physiological analyses showed that sga1-2 salt hypersensitivity is linked to an increase of Na+ and water transport from roots to shoots, which explains their extreme chlorosis and hyperhydration under salinity conditions. At the molecular level, SlPIP2;12 gene, an aquaporin down-regulated in the WT under salt stress, was overexpressed in the sga1-2 mutants, which could enhance water transport to the shoot. Also, sga1-2 mutants exhibited a significant reduction in the expression of key sodium transporters, thus modifying the normal distribution of Na+ in tomato plant tissues. Furthermore, treatment of WT plants with the NADPH oxidase inhibitor DPI prevented H2O2 production in response to salinity, resulting in elevated Na+ accumulation in the shoot and reduced expression of the SlHKT1;2 gene in root. Altogether, our results show that SlRbohG plays a central role in salt tolerance through ROS-mediated signaling. HIGHLIGHTLoss of function of tomato SlRbohG gene leads hypersensibility to salt stress due to increased Na+ and water transport from root to shoot.

plant biology↗

bioRxiv2021

Tomato CRABS CLAW paralogues interact with chromatin remodelling factors to mediate carpel development and floral determinacy

CRABS CLAW (CRC) orthologues play a crucial role in floral meristem (FM) determinacy and gynoecium formation across angiosperms, key developmental processes for ensuring successful plant reproduction and crop production. Here, we revealed that the incomplete penetrance and variable expressivity of the carpel-inside-carpel phenotype observed in flowers of the tomato fruit iterative growth (fig) mutant is due to a lack of function of a homologue of the CRC gene, Solanum lycopersicum CRCa (SlCRCa). Likewise, a comprehensive functional analysis of SlCRCa and SlCRCb paralogues, including Arabidopsis complementation experiments, allowed us to propose that they operate as positive regulators of FM determinacy by acting in a compensatory and partially redundant manner to safeguard the proper formation of flowers and fruits. Furthermore, we provide the first evidence for the role of putative CRC orthologues as members of the chromatin remodelling complex that terminates floral stem cell activity by repressing WUSCHEL expression.

developmental biology↗