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Biology subjects

An, E.

Publications and source records attributed to An, E..

4 recordsLinked to original sources

The FUL-SHP-AP2 module regulates fruit development in petunia

Fruit development is a typical angiosperm feature that greatly facilitates seed dispersal. Despite extensive studies on the gene regulatory network underlying pod shattering in the dry Arabidopsis fruit and the ripening process in the fleshy tomato fruit, it is yet unclear if a conserved regulatory network acts in early fruit development. Here, we investigated the roles of Petunia x hybrida (petunia) FRUITFULL (FUL), SHATTERPROOF (SHP) and APETALA 2 (AP2) homologs, three types of transcription factors repeatedly associated with fruit development and/or ripening. Petunia is closely related to tomato but produces dry dehiscent fruits like Arabidopsis. Our functional analysis revealed that the three petunia FUL-like genes, PETUNIA FLOWERING GENE (PFG), FLORAL BINDING PROTEIN 26 (FBP26) and FBP29, redundantly regulate endocarp development. They promote the formation of regularly shaped inner endocarp cells, probably via auxin/brassinosteroid signalling and cell wall modification. Furthermore, we discovered that the SHP-like gene FLORAL BINDING PROTEIN 6 (FBP6) has an opposite role, promoting more mesocarp-shaped endocarp cells, indicating that the FUL-like and SHP-like genes act antagonistically in early pericarp development. Finally, we show that the AP2-like genes REPRESSOR OF B-FUNCTION 1 (ROB1), ROB2 and ROB3 are crucial factors in petunia fruit development. rob1 rob2 rob3 mutants completely fail to dehisce and show major defects in pericarp patterning. The ROB transcription factors repress the activity of the FUL-like genes, and have, together with FBP6, an opposite effect on auxin and brassinosteroid signalling genes. Our study suggests that a module consisting of antagonistically acting TFs, including co-orthologs of AP2, FUL and SHP, regulates early pericarp patterning, at least partially via auxin and brassinosteroids.

plant biology↗

Long-term Immunity of a Microneedle Array Patch of SARS-CoV-2 S1 Protein Subunit Vaccine Irradiated by Gamma Rays in Mice

COVID-19 vaccines effectively prevent symptomatic infection and severe disease, including hospitalization and death. However, unequal vaccine distribution during the pandemic, especially in low- and middle-income countries, has led to the emergence of vaccine-resistant strains. This underscores the need for alternative, safe, and thermostable vaccine platforms, such as dissolved microneedle array patches (MAP) delivering a subunit vaccine, which eliminate the need for cold chain and trained healthcare personnel. This study demonstrates that the SARS-CoV-2 S1 monomer with RS09, a TLR-4 agonist peptide, serves as an optimal protein subunit immunogen. This combination stimulates a stronger S1-specific immune response, resulting in binding to the membrane-bound spike on the cell surface and ACE2-binding inhibition, compared to the monomer S1 alone or trimer S1, regardless of RS09. MAP delivery of the rS1RS09 subunit vaccine elicited higher and longer-lasting immunity compared to conventional intramuscular injection. S1-specific IgG levels remained significantly elevated for up to 70 weeks post-administration. Additionally, different doses of 5, 15, and 45 g of MAP vaccines induced robust and sustained Th2-prevalent immune responses, suggesting a dose-sparing effect and inducing significantly high neutralizing antibodies against the Wuhan, Delta, and Omicron variants at 15 and 45 g dose. Moreover, gamma irradiation as a terminal sterilization method did not significantly affect immunogenicity, with irradiated vaccines maintaining comparable efficacy to non-irradiated ones. The stability of MAP vaccines was evaluated after long-term storage at room temperature and refrigeration for 19 months, showing minimal protein degradation. Further, after an additional one-month of storage at elevated temperature (42{degrees}C), rS1RS09 in both non-irradiated and irradiated MAP degraded less than 3%, while the liquid subunit vaccine degraded over 23%. Overall, these results indicate that gamma irradiation sterilized MAP-rS1RS09 vaccines maintain stability during extended storage without refrigeration, supporting their potential for mass production and widespread use in global vaccination efforts.

microbiology↗

Fourth dose of Microneedle Array Patch of SARS-CoV-2 S1 Protein Subunit Vaccine Elicits Robust Long-lasting Humoral Responses in mice

The COVID-19 pandemic has underscored the pressing need for safe and effective booster vaccines, particularly in considering the emergence of new SARS-CoV-2 variants and addressing vaccine distribution inequalities. Dissolving microneedle array patches (MAP) offer a promising delivery method, enhancing immunogenicity and improving accessibility through the skins immune potential. In this study, we evaluated a microneedle array patch-based S1 subunit protein COVID-19 vaccine candidate, which comprised a bivalent formulation targeting the Wuhan and Beta variant alongside a monovalent Delta variant spike proteins in a murine model. Notably, the second boost of homologous bivalent MAP-S1(WU+Beta) induced a 15.7-fold increase in IgG endpoint titer, while the third boost of heterologous MAP-S1RS09Delta yielded a more modest 1.6-fold increase. Importantly, this study demonstrated that the administration of four doses of the MAP vaccine induced robust and long-lasting immune responses, persisting for at least 80 weeks. These immune responses encompassed various IgG isotypes and remained statistically significant for one year. Furthermore, neutralizing antibodies against multiple SARS-CoV-2 variants were generated, with comparable responses observed against the Omicron variant. Overall, these findings emphasize the potential of MAP-based vaccines as a promising strategy to combat the evolving landscape of COVID-19 and to deliver a safe and effective booster vaccine worldwide.

immunology↗

OligoTRAFTACs: A Generalizable Method for Transcription Factor Degradation

Dysregulated transcription factors (TFs) that rewire gene expression circuitry are frequently identified as key players in disease. Although several TFs have been drugged with small molecules, the majority of oncogenic TFs are not currently pharmaceutically tractable due to their paucity of ligandable pockets. The first generation of transcription factor targeting chimeras (TRAFTACs) was developed to target TFs for proteasomal degradation by exploiting their DNA binding ability. In the current study, we have developed the second generation TRAFTACs ("oligoTRAFTACs") comprised of a TF- binding oligonucleotide and an E3 ligase-recruiting ligand. Herein, we demonstrate the development of oligoTRAFTACs to induce the degradation of two oncogenic TFs, c-Myc and brachyury. In addition, we show that brachyury can be successfully degraded by oligoTRAFTACs in chordoma cell lines. Furthermore, zebrafish experiments demonstrate in vivo oligoTRAFTAC activity. Overall, our data demonstrate oligoTRAFTACs as a generalizable platform towards difficult-to-drug TFs and their degradability via the proteasomal pathway.

cancer biology↗