The annexin family of proteins plays pivotal roles in regulating various physiological processes, particularly within the plant kingdom, and new insights reveal their importance across diverse maize genomes.
Utilizing cutting-edge bioinformatic analyses of 26 high-quality maize genomes, researchers have identified 12 annexin (Ann) genes, which comprise 9 core genes consistently present across all maize lines and 3 near-core genes found in most. This compelling study highlights the limitations associated with using single reference genomes for such analyses, offering significant insights about maize development and its capacity for stress response.
The significance of these findings stems from the increasing necessity to improve crop resilience, particularly as global food security remains under threat due to climate change. By elucidation of the evolution, variation, and expression patterns of the annexin gene family, this research signifies how genetic diversity can confer advantages to maize, especially during unfavorable conditions.
Notably, the research documents how different varieties of maize exhibit varying genetic expressions of annexin genes under stress conditions. The evaluations of the genes’ Ka/Ks values suggest positive selection acting on ZmAnn10 genes within specific maize varieties, potentially enhancing their adaptability and evolutionary fitness.
Researchers state, 'Using the pan-genome of 26 high-quality maize genomes, we identified 12 Annexin genes, comprising 9 core genes and 3 near-core genes.' The comprehensive characterization of these genes underlines their evolutionarily conserved nature and diverse functional roles when confronted with abiotic and biotic stresses.
Through transcriptomic analysis, it was observed how different Ann members had distinct expression patterns, particularly when subjected to various stressors like cold temperatures, drought, and pathogen attacks. For example, during cold stress conditions, the expression levels of the ZmAnn2, ZmAnn4, ZmAnn6, and ZmAnn8 genes surged significantly, indicating their key roles in aiding maize's adaptability to environmental fluctuations.
The study emphasizes structural variations (SVs) within the maize genomes, citing how these variations can influence gene expression and functional diversity of the annexin family. 'Evaluations indicated significant differences between gene expression levels of ZmAnn2 and ZmAnn11, which are influenced by structural variations,' states the research team, supporting the notion of proper adaptation through genetic flexibility.
Following extensive analysis, the team constructed weighted gene co-expression networks, illustrating potential regulatory networks involving the annexin proteins, particularly under cold stress. Here, genes such as ZmAnn2 and ZmAnn7 surfaced as significant players within the temperature-response regulatory frameworks.
Overall, these revelations not only paint a clearer picture of the annexin gene family's roles across diverse maize genomes but also underline the importance of continued exploration within the realms of pan-genomics for crop improvement strategies needed to combat environmental challenges. This work paves the way for future investigations aimed at leveraging genetic diversity to bolster crop resilience, ensuring food security against the backdrop of climate change.