AUTHOR=Xu Huilong , Wang Yongsheng , Chen Zhiming , Huang Rongyu , Liu Xinyu , Pan Mengting , Yang Nan , Chen Lianghua , Xu Wen , Chen Fangyu 

TITLE=Dynamic proteomics reveals that endosperm weakening plays a critical role during seed germination in Polygonatum cyrtonema Hua

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 16 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2025.1662175

DOI=10.3389/fpls.2025.1662175

ISSN=1664-462X

ABSTRACT=IntroductionPolygonatum cyrtonema Hua, a valued Chinese medicinal herb, faces challenges in cultivation and seedling quality due to seed dormancy, a combinational type resulting from multiple factors whose molecular mechanisms remain unclear.MethodsThis study employed iTRAQ-based proteomics, transcriptomics, and hormone profiling to analyze three key germination stages (S1, pulp removal and initial imbibition. S2, radicle emergence through the seed coat. S3, transition phase between primary root elongation and cotyledon emergence).ResultsMorphological observations indicated gradual endosperm weakening and embryo development during germination. Transcriptomics highlighted 30 enriched pathways, notably plant hormone signaling and starch and sucrose metabolism. Proteomics revealed consistent enrichment of FOG: RRM domain, aspartyl protease, and β-fructofuranosidase across comparisons. Hormone assays showed decreases in ABA, bioactive GAs, IAA, JA, and SA from S1 to S3, with a marked increase in the bioactive GAs/ABA ratio. Integrated omics emphasized metabolism and hormone signal transduction. Key enzymes in starch and sucrose metabolism (e.g., β-fructofuranosidase, α-xylosidase, β-D-xylosidase, and β-glucosidase) increased, supporting energy conversion and endosperm weakening. Conversely, ABA-related proteins (PYL4, PP2C) decreased. Sucrose synthase, involved in ABA-GA antagonism, also declined.DiscussionThese results underscore synergistic endosperm weakening and hormonal regulation during P. cyrtonema seed germination, offering new insights for improving germination in species constrained by endosperm strength.