Despite advances in plant sex-determination research, understanding these mechanisms remains complex due to the intricate interactions between genes and environmental factors. Ficus hispida presents a rare opportunity to study dioecy, where plants exist as distinct male or female individuals. Its specialized relationship with fig wasps, who rely on figs to reproduce, adds unique biological layers to this research. Addressing these challenges required a comprehensive, high-quality genome sequence to explore fig-wasp interdependence and sex differentiation.
Published (DOI: 10.1093/hr/uhad257) on December 13, 2024, in Horticulture Research, this study was conducted by the Agricultural Genomics Institute at Shenzhen and Xishuangbanna Tropical Botanical Garden. Using PacBio HiFi and Oxford Nanopore sequencing, researchers created a telomere-to-telomere (T2T) genome of F. hispida. They identified crucial sex-determining genes within the male-specific genomic region, deepening the understanding of reproductive biology in figs and their evolutionary symbiosis with wasps.
The newly assembled T2T genome represents a major advance, providing a more complete and contiguous reference than previous versions. Researchers identified a 7.2 Mb male-specific region containing the AG2 and AG3 genes, which regulate stamen development in male flowers. High methylation in this region suggests that epigenetic factors may contribute to sex differentiation. Furthermore, gene regulatory networks (GRNs) in male and female flowers revealed distinct transcription factor families, with MADS and MYB factors prominent in males, and NAC and WRKY in females, advancing the understanding of sex-specific plant biology and the fig-wasp co-evolutionary process.
Dr. Zhenyang Liao, the study's lead researcher, remarked, “This complete genome fills significant gaps in our understanding of Ficus hispida sex determination. By characterizing these male-specific regions, we gain insights not only into plant biology but also into the intricate fig-wasp relationship, which is vital for biodiversity in tropical ecosystems.”
The study’s findings offer broader implications for plant breeding and conservation by uncovering the genetic mechanisms underlying plant sex differentiation. This research could support breeding programs for dioecious plants and enable deeper investigations into symbiotic relationships across ecosystems, paving the way for future studies in plant reproductive biology and genetic engineering of crops with tailored sex traits.
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References
DOI
Original Source URL
https://doi.org/10.1093/hr/uhad257
Funding information
This work was supported by the National Natural Science Foundation of China (grant 32200188) and the Key Programs of Jiangxi Youth Science Foundation (grant 20202ACBL215008).
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2022. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.