Isolation and Characterization of NAC Family Genes Responding to Environmental Stress in Creeping Bentgrass

Bo-Hwa  Kim2   Hyeon-Jin  Sun1   Hyo-Yeon  Lee1,*   Hong-Gyu  Kang1   

1Subtropical Horticulture Research Institute, Jeju National University, Jeju 63243, Korea
2Agricultural Technology Institute, Jeju Special Self-Governing Province, Jeju 63556, Korea


All kinds of crops including foods, feeds, and turf grasses are damaged frequently by various environmental stresses such as drought, salt, and high temperature, which cause the loss of agronomic productivity and the decline in commercial quality. Many abiotic stress responsive genes have been identified in plants and they have been applied to breed crops tolerant to environmental stresses through a transgenic approach. In this study, by use of 4 combinations of degenerate primer PCR and Rsa I, a 4-cutter restriction enzyme recognizing GTAC, 9 independent cDNAs containing NAC domain sequence were isolated from creeping bentgrass (Agrostis stolonifera L. cv penncross). Among them, the 5 clones including AsNAC18, AsNAC19, AsNAC20, AsNAC23, and AsNAC24 belonged to NAM and CUC2 subfamily regulating development and the other 4 including AsNAC16, AsNAC17, AsNAC21 and AsNAC22 belonged to ATAF and SNAC1 subfamily regulating defense to abiotic stress. In mRNA expression analysis, AsNAC16, AsNAC17 and AsNAC19 were upregulated in the senescence leaf. AsNAC17, AsNAC18, AsNAC22 and AsNAC24 were upregulated by dark stress and AsNAC22 mRNA was also increased by heat stress as well as dark. It is considered that these genes are important as a gene pool for plant biotechnology.

Figures & Tables

Fig. 1. Isolation of NAC cDNAs from creeping bentgrass using conserved domains of NAC proteins in . (A) Comparison of amino acid sequences of NAC domains consisting of 5 subdomains (A to E) from A. thaliana respectively. (B) Experimental scheme to isolate NAC cDNAs of creeping bentgrass by PCR using degenerate primers based on conserved amino acid sequence domains. (C) Cloning and screening of PCR products into a T-plamid vector. Lane 1 to 4 are RT-PCR products. Lane 1 NAC F1 and NAC R1. Lane 2 NAC F1 and NAC R2. Lane 3 NAC F2 and NAC R1. Lane 4 NAC F2 and NAC R2.