Transcriptomic profiling identifies differentially expressed genes associated with programmed cell death of nucellar cells in Ginkgo biloba L.

作者：Dahui Li, Di Wu, Shizhou Li, Ning Guo, Junshan Gao, Xu Sun, Yongping Cai · 发表于：BMC Plant Biology · 年份：2019 · DOI：10.1186/s12870-019-1671-8 · 被引用次数：28 · 研究领域：Plant Reproductive Biology、Ginkgo biloba and Cashew Applications、Plant Molecular Biology Research

BACKGROUND: Previously, we demonstrated that pollen chamber formation (PCF) in G. biloba ovules was a process of programmed cell death (PCD) within the nucellar cells at the micropylar end. However, the signal triggering the cascades of the programmed events in these nucellar cells remains unexplored. RESULTS: A transcriptomic strategy was employed to unravel the mechanism underlying the nucellar PCD via the comparative profiles of RNA-seq between pre-PCF and post-PCF ovules. A total of 5599 differentially expressed genes (DEGs) with significance was identified from G. biloba ovules and classified into three main categories of GO annotation, including 17 biological processes, 15 cellular components and 17 molecular functions. KEGG analysis showed that 72 DEGs were enriched in "Plant hormone signal transduction". Furthermore, 99 DEGs were found to be associated with the PCD process, including the genes involved in ethylene signaling pathway, PCD initiation, and PCD execution. Moreover, calcium-cytochemical localization indicated that calcium could play a role in regulating PCD events within the nucellar cells during pollen chamber formation in G. biloba ovules. CONCLUSIONS: A putative working model, consisting of three overlapping processes, is proposed for the nucellar PCD: at the stage of PCD preparation, ethylene signaling pathway is activated for transcriptional regulation of the downstream targets; subsequently, at the stage of PCD initiation, the upregulated expression o...