From Single Cells to Flowers – Biological Complexity Driving Plant Reproductive Development

The rise of data science in biology stimulates interdisciplinary collaborations to address fundamental questions. Here, we report the outcome of the first SINFONIA symposium focused on revealing the mechanisms governing plant reproductive development across biological scales. The intricate and dynamic target networks of known regulators of flower development remain poorly understood. To analyze development from the genome to the final floral organ morphology, high-resolution data that capture spatiotemporal regulatory activities are necessary and require advanced computational methods for analysis and modeling. Moreover, frameworks to share data, practices and approaches that facilitate the combination of varied expertise to advance the field are called for. Training young researchers in interdisciplinary approaches and science communication offers the opportunity to establish a collaborative mindset to shape future research.

Characterization of Heat Responsive microRNAs and Phased Small Interfering RNAs in Reproductive Development of Flax

Plants will face increased heat stress due to rising global temperatures. Heat stress affects plant reproductive development and decreases productivity; however, the underlying molecular mechanisms of these processes are poorly characterized. Plant small RNAs (sRNAs) have important regulatory roles in plant reproductive development following abiotic stress responses. We generated sRNA transcriptomes of three reproductive bud stages at three different time points to identify sRNA-mediated pathways responsive to heat stress in flax. With added sRNA transcriptomes of vegetative tissues, we comprehensively annotated miRNA and phasiRNA-encoding genes (PHAS) in flax. We identified 173 miRNA genes, of which 42 are novel. Our analysis revealed that 141 miRNA genes were differentially expressed between tissue types while 18 miRNA genes were differentially expressed in reproductive tissues following heat stress, including members of miR2118/482 and miR2275 families, known triggers of reproductive phasiRNAs. Furthermore, we identified 68 21-PHAS flax loci from protein coding and non-coding regions, four 24-PHAS loci triggered by miR2275, and 658 24-PHAS-like loci with unknown triggers, derived mostly from non-coding regions. The reproductive phasiRNAs are mostly downregulated in response to heat stress. Overall, we found that several previously unreported miRNAs and phasiRNAs are responsive to heat stress in flax reproductive tissues.

Roles of cytochromes P450 in plant reproductive development

The cytochrome P450 superfamily is a large enzymatic protein family that is widely distributed along diverse kingdoms. In plants, CYPs participate in a vast array of pathways leading to the synthesis and modification of multiple metabolites with variable and important functions during different stages of plant development. This includes the biosynthesis and degradation of a great assortment of compounds implicated in a variety of physiological responses such as signaling and defense, organ patterning and the biosynthesis of structural polymers among others. In this review we summarize the characteristics of the different families of plant CYPs, focusing on the most recent advances in elucidating the roles of CYPs in plant growth and development and more specifically, during plant gametogenesis, fertilization and embryogenesis.

Long Non-Coding RNAs: Rising Regulators of Plant Reproductive Development

Long non-coding RNAs (lncRNAs) exert a multitude of functions in regulating numerous biological processes. Recent studies have uncovered a growing number of lncRNAs within the plant genome. These molecules show striking tissue-specific expression patterns, suggesting that they exert regulatory functions in the growth and development processes of plants. Plant reproductive development is tightly regulated by both environmental and endogenous factors. As plant reproductive development is a crucial aspect of crop breeding, lncRNAs that modulate reproductive development are now particularly worth regarding. Here, we summarize findings that implicate lncRNAs in the control of plant reproductive development, especially in flowering control. Additionally, we elaborate on the regulation mechanisms of lncRNAs, tools for research on their function and mechanism, and potential directions of future research.