Fuente: PubMed "stone fruits" Int J Biol Macromol. 2025 Nov 9;333(Pt 2):148906. doi: 10.1016/j.ijbiomac.2025.148906. Online ahead of print.ABSTRACTPlums are economically important stone fruits, valued for their nutritional quality and health-promoting properties. However, their quality and marketability are often compromised by a physiological disorder called fruit hollowness and browning (HB). This study employed an integrated physiological, biochemical, and proteomic approach to investigate the molecular mechanisms underlying HB in Huangguan plum. Huangguan plum fruit samples from seven developmental stages were analyzed for lignin content, key enzyme activities, and expression patterns of genes involved in lignin biosynthesis. The results demonstrated that HB-affected fruit accumulated significantly higher lignin levels, particularly during post-veraison stages, accompanied by elevated activities of lignin biosynthesis-related enzymes like phenylalanine ammonia-lyase and laccase. Expression analysis of lignin pathway genes revealed distinct transcriptional dynamics, with notable upregulation of PsPAL1 and PsLAC7 in HB fruit at critical developmental stages. Proteomic profiling identified 941 and 1249 differentially expressed proteins between HB and non-HB fruit at the veraison and ripe stages, respectively. KEGG enrichment analysis highlighted significant alterations in the phenylpropanoid biosynthesis pathway (map00940), which is central to lignification. These findings provide new insights into the physiological and molecular basis of HB in plum fruit and a scientific foundation for developing effective strategies to mitigate or address this disorder and improve fruit quality.PMID:41218665 | DOI:10.1016/j.ijbiomac.2025.148906