含热带种质玉米自交系ZOL-1 胚乳发育的转录组研究.

[Objective] The present paper aims to investigate the molecular mechanisms and associated regulatory networks involved in endo- sperm development for the tropical maize inbred line. (Method) The study employed high-throughput RNA-Seq sequencing technology to compare the endosperm transcriptome of the tropical inbred maize line ZOL-1 at six stages after pollination, including 5 (day after pollination), 10, 15, 20, 25 and 30 days. Differentially expressed genes were annotated with KEGG and GO functions, and time-series analysis was conducted on genes with an average FPKM value greater than 1. [Result] The endosperm development of the maize inbred line ZOL-1 exhibited the fastest growth rate in grain length, width, and thickness at 25-30 days after pollination, with growth rates reaching 15.9%, 16.1% and 10.2%, respectively. Following transcriptome sequencing and comparison with the reference genome, the percentage of filtered reads was at least 83.99%, indicating good sequencing quality and assembly. A total of 7129, 5252, 4254, 775 and 312 differentially ex- pressed genes were identified between 10 d_VS_5 d, 15 d_VS_10 d, 20 d_VS_15 d, 25 d_VS_20 d and 30 d_VS_25 d, based on the sequential comparison system approach. GO functional annotation indicated that the differentially expressed genes were mainly involved in cell differentiation process, metabolic process, catalytic activity and organelles. KEGG functional enrichment analysis revealed that differentially expressed genes were mainly enriched in pathways related to energy metabolism, carbohydrate metabolism, carbon metabolism, amino acid metabolism, signal transduction, and other processes associated with endosperm development. Through time-series analysis of genes with an FPKM mean greater than 1, 19 554 genes were classified into 10 clusters. In Cluster 7, eight starch synthase-related genes were identified, showing a significant increase in expression starting at the 15-day period and maintaining a high expression level thereafter. (Conclusion] The regulation of endosperm development in maize self-incompatible lines appears to be primarily governed by the expression of down-regulated genes. The developmental pattern of the endosperm undergoes a significant change before and after 15 days, indicating a transcriptome reprogramming. Additionally, the study identifies eight genes associated with maize starch biosynthesis, providing valuable insights into the molecular regulatory mechanisms of endosperm development. [ABSTRACT FROM AUTHOR]