移動 mRNA 在植物器官間通訊中作為長距離訊號分子發揮重要作用。本研究旨在探討源庫調控（source–sink manipulation）對番茄（Solanum lycopersicum cv. Moneymaker）與菸草（Nicotiana tabacum cv. Turkish）異種嫁接系統中移動 mRNA 的影響。研究設置三種嫁接處理：(1) 保留砧木葉片並去除接穗成熟葉片；(2) 保留砧木與接穗的所有葉片；以及 (3) 去除所有砧木葉片。RT-PCR 分析結果顯示，在番茄–菸草及菸草–番茄異種嫁接組合中，於保留砧木葉片並去除接穗成熟葉片的處理下均檢測到 NsMFTL2 與 SP9D 轉錄本。移動 mRNA 可於嫁接後第 2 至第 5 週期間被檢測到，其中在嫁接發育早期階段觀察到較強的轉錄本訊號。相較之下，當砧木與接穗均保留葉片時，移動 mRNA 的訊號強度較弱。此外，在去除所有砧木葉片的處理中，未檢測到可辨識的移動 mRNA 訊號。研究結果顯示，源庫關係及葉片保留條件會影響嫁接植物中移動 mRNA 的長距離運輸。總體而言，本研究證實移動 mRNA 能夠跨越番茄與菸草之間的嫁接接合部位進行運輸，並凸顯源組織在異種嫁接過程中調控轉錄本運輸的重要性。;Mobile mRNA functions as a long-distance signaling molecule in interorgan communication in plants. This study aimed to investigate effect of source-sink manipulation on mobile mRNA in tomato (Solanum lycopersicum cv. Moneymaker) and tobacco (Nicotiana tabacum cv. Turkish) heterografting. Three grafting treatments were applied: retaining the rootstock leaves and removing the mature scion leaves， retaining all leaves in both grafting pairs， and removing all rootstock leaves. RT-PCR results showed that gene marker NsMFTL2 and SP9D transcripts were detected in both tomato–tobacco and tobacco–tomato heterografts in the treatment of retaining the rootstock leaves and removing the mature scion leaves. Mobile mRNA was detected from 2 to 5 weeks after grafting， with stronger signals observed during the earlier stages of graft development. In contrast， a weaker signal was observed when leaves were maintained in both the rootstock and scion. Furthermore， no detectable mobile mRNA signal was observed when all rootstock leaves were removed. Based on these findings， indicate that the source-sink relationship and leaf retention condition impact the long-distance transport of mobile mRNA in grafted plants. Overall， this study demonstrates that mobile mRNA movement occurs across the graft junction between tomato and tobacco and highlights the importance of the source tissue in regulating transcript transport during heterografting.
