Hongjian Zhang

Virulent phage vB_PmuP_Pa7 is a promising candidate for controlling Pasteurella multocida infection, yet the molecular basis of its lytic process remains poorly understood. Here, we performed strand-specific RNA sequencing on P. multocida S34 infected with Pa7 at 0, 20, 30, and 120 min to characterize phage–host transcriptional dynamics. A total of 234, 433, and 558 differentially expressed genes (DEGs) were detected at 20, 30, and 120 min, respectively, indicating progressive host reprogramming during infection. PCA, expression distribution analysis, and sample correlation analysis confirmed clear stage-specific transcriptional shifts. GO and KEGG enrichment analyses indicated that Pa7 infection was associated with changes in translation, ribosome function, ABC transporters, amino sugar and nucleotide sugar metabolism, bacterial chemotaxis, and the TCA cycle. Four representative differentially expressed genes involved in transport, carbohydrate metabolism, and translation-related functions were selected for RT-qPCR analysis. The RT-qPCR results showed partial, gene- and time-point-dependent agreement with the RNA-seq-derived expression patterns. Together, these findings provide a time-resolved transcriptional profile of Pa7 infection and identify host pathways potentially associated with the infection process and bacterial cell lysis. However, the direct functional contributions of these genes and pathways remain to be experimentally determined.