Biology subjects

Bollier, N.

Publications and source records attributed to Bollier, N..

5 recordsLinked to original sources

bioRxiv2025

Functional analysis of FW2.2-LIKE proteins in tomato: SlFWL5 regulates leaf size and morphology.

The CELL NUMBER REGULATOR/FW2.2-like (CNR/FWL) gene family comprises PLAC8 domain-containing membrane-associated proteins. The CNR/FWL gene family was named in reference to its founding member, the FW2.2 gene, which determines fruit size in tomato via a negative regulation on cell divisions. The functional characterization of PLAC8 domain-containing CNR/FWL proteins in plants is still very scarce, and only recently the molecular and cellular mode of action of FW2.2 was identified as regulating plasmodesmata-mediated cell-to-cell communication. In the present study, we provided a functional analysis of SlFWL genes in tomato, aiming at investigating any direct role in the control of organ growth. Based on a combination of molecular and cellular approaches, we selected three SlFWL proteins, namely SlFWL2, -4 and -5, which are localized at the plasma membrane. Gain- and loss-of-function transgenic plants were generated to explore their putative role as regulators of organ growth in tomato. This allowed us to shed light more specifically on the critical involvement of SlFWL5 in leaf development. We here showed that SlFWL5 is a plasmodesmata-localized protein that regulates leaf size and morphology via cell expansion, most probably through cell-to-cell communication. This original finding underscores further the importance of the CNR/FWL family members in growth regulation. Highlight: The FW2.2-LIKE protein SlFWL5 is localized at plasmodesmata and may have a role in cell-to-cell communication to regulate cell expansion during leaf development.

plant biology↗

bioRxiv2024

Modulating activity of the APC/C regulator SlSAMBA improves the sugar and antioxidant content of tomato fruits

The Anaphase-Promoting Complex/Cyclosome (APC/C) is an E3 ubiquitin ligase that plays a crucial role in ubiquitin-dependent proteolysis of key cell cycle regulators, which is completed by 26S proteasome. Previously, SAMBA, a plant-specific regulator of the APC/C, was identified in Arabidopsis as a critical factor controlling organ size through the regulation of cell proliferation. Here, by assessing its role in the crop tomato (Solanum lycopersicum), we confirm that SAMBA is a conserved APC/C regulator in plants. Two slsamba genome-edited lines were characterized showing delayed growth, reduced plant size and altered fruit morphology, which were linked to changes in cell division and expansion. Notably, untargeted metabolomics revealed altered flavonoid profiles, along with elevated Brix values in the fruits, indicating a sweeter taste. Accordingly, transcriptomics uncovered a change in temporal gene expression gradients during early fruit development, correlating with the alterations in sugar metabolism and revealing changes in cell wall biosynthesis genes. This study provides the first evidence of SAMBAs role in regulating fruit development, metabolic content, and, ultimately, quality. These important findings offer potential applications for improving the nutritional quality and overall performance of tomato.

plant biology↗

bioRxiv2023

The FW2.2/CNR protein regulates cell-to-cell communication in tomato by modulating callose deposition at plasmodesmata

The FW2.2 gene is the founding member of the CELL NUMBER REGULATOR (CNR) gene family. More than 20 years ago, FW2.2 was the first cloned gene underlying a Quantitative Trait Locus (QTL) governing fruit size/weight in tomato. However, despite this discovery, the molecular mechanisms by which FW2.2 acts as a negative regulator of cell divisions during fruit growth remain undeciphered. In the present study, we confirm that FW2.2 is a transmembrane spanning protein, whose both N- and C-terminal ends are facing the apoplast. We unexpectedly found that FW2.2 is located at plasmodesmata (PD). FW2.2 participates in the spatiotemporal regulation of callose deposition at PD via an interaction with Callose Synthases, which suggests a regulatory role in cell-to-cell communication by modulating PD transport capacity and trafficking of signaling molecules during fruit development.

plant biology↗

bioRxiv2022

Various tomato cultivars display contrasted morphological and molecular responses to a heat wave.

Climate change is one of the biggest threats that human society currently needs to face. Heat waves associated with global warming negatively affect plant growth and development and will increase in frequency. Tomato is one of the most produced and consumed fruit in the world but remarkable yield losses occur every year due to the sensitivity of many cultivars to heat stress. New insights into how tomato plants are responding to heat waves will contribute to the development of new cultivars with high yields under harsh temperature conditions. In this study, the analysis of microsporogenesis and pollen germination rate of eleven tomato cultivars after exposure to a simulated heat wave revealed differences between genotypes. The transcriptome of floral buds at two developmental stages of five cultivars selected based on their pollen germination tolerance or sensitivity, revealed common and specific molecular responses implemented by tomato cultivars to cope with heat waves. These data provide valuable insights into the underlying molecular adaptation of floral buds to heat stress and will contribute to the development of future climate resilient tomato varieties.

plant biology↗

bioRxiv2020

Efficient simultaneous mutagenesis of multiple genes in specific plant tissues by multiplex CRISPR

Multiplex CRISPR approaches enable mutating multiple genes in plants, however it is unclear how feasible this is in tissue-specific mutagenesis. Here we simultaneously mutated six genes either ubiquitously or exclusively in the root cap of Arabidopsis. The mutation frequencies for all target genes were positively correlated and unaffected by the order of gRNAs in the vector, indicating that efficient higher-order mutagenesis in specific plant tissues can be readily achieved.

plant biology↗