| Summary: | NAC transcription factors (TFs) play important roles in plants’ responses to abiotic stresses and developmental processes, including leaf senescence. Oriental melon (<i>Cucumis melo</i> var. <i>makuwa</i> Makino) is an important vegetable crop in China and eastern Asia countries. However, little is known about the functions of the melon NAC family members. In this study, a phylogenetic tree was constructed to show that CmNAC60 and the senescence regulator AtNAP were in the same cluster, which implied that CmNAC60 might be a NAC related to leaf senescence. The expression analysis of <i>CmNAC60</i> in different melon organs showed that the expression of <i>CmNAC60</i> was highest in the male flowers and lowest in the hypocotyl. In addition, the expression level of <i>CmNAC60</i> in the senescing leaves was significantly higher than in the non-senescing leaves. Similarly, the expression level of <i>CmNAC60</i> in the dark-treated leaves was significantly higher than in the untreated leaves. Furthermore, the subcellular localization and transcriptional activation assays indicated that CmNAC60 was a nucleus localized NAC transcription factor with a C-terminal transactivation domain. An analysis of the tissue specific expression showed that the promoter of <i>CmNAC60</i> may contain <i>cis</i>-acting regulatory elements responsive to leaf senescence. <i>CmNAC60</i> overexpressing lines of <i>Arabidopsis</i> showed a precocious senescence compared with the wild type (WT). Collectively, our results showed that <i>CmNAC60</i> was associated with leaf senescence, and could be potentially utilized in molecular breeding to improve melon yield or to extend the postharvest shelf life by delaying leaf senescence.
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