Transcriptional regulation of the SCI1 gene and its role in floral development

• Grant number: 23/11715-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: April 01, 2024
• End date: March 31, 2026
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Maria Helena de Souza Goldman
• Grantee: Fernando Bonifácio Anacleto
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 19/24774-1 - The importance of the SCI1 gene in the floral meristem, its transcriptional regulation and evolutionary conservation, AP.TEM

Abstract

Understanding flower development and the reproductive processes in plants holds significant importance for maintaining biodiversity and ensuring food production. Extensive research has explored the molecular mechanisms governing floral development. The SCI1 gene has been identified as a pivotal regulator of cell proliferation, exerting influence over the final size of the pistil, the female reproductive organ responsible for giving rise to fruits and seeds post-fertilization. Through in situ hybridizations, it has been demonstrated that the SCI1 gene is expressed from floral meristem specification onwards and maintains this expression in all floral meristematic cells. Bioinformatic analyses of the genomic sequence of SCI1 in Nicotiana tabacum have unveiled the presence of cis-regulatory elements for various transcription factors (TFs) including AGAMOUS (AG), AINTEGUMENTA (ANT), AINTEGUMENTA-LIKE 2 (AIL2)/BABY BOOM (BBM), AIL6, LEAFY (LFY), and WUSCHEL (WUS), which play crucial roles in floral development. Interactions of AG and WUS in the SCI1 promoter have previously been demonstrated through Yeast One Hybrid (Y1H), electrophoretic mobility shift assays (EMSA), and luciferase assays. More recently, the interaction of ANT with the genomic sequence of SCI1 has also been confirmed. In the context of the present project, the investigation aims to explore the potential regulation of SCI1 expression by LFY, AIL2/BBM, and/or AIL6, thereby expanding the comprehension of the transcriptional regulation of SCI1 and its interplay with floral development. Additionally, we intend to generate CRISPR knockout plants for the SCI1 gene and analyze floral development in the complete absence of SCI1 expression. It is noteworthy that, thus far, no plants lacking SCI1 expression have been reported across the studied species, including Arabidopsis thaliana mutants available in international mutant repositories. The application of CRISPR technology is anticipated to facilitate the generation of SCI1 knockout mutants, enabling a meticulous analysis of floral development in the absence of this protein. This study not only aims to elucidate the role of SCI1 in the process but also has the potential to provide invaluable insights into the broader regulation of floral development.