Functional analysis of ZjCIGR1 gene in Zoysia japonica and Arabidopsis thaliana

Abstract

Zoyia japonica Steud. is a warm-season lawn grass popular in Korea and cultivated in many places such as river banks, roadside and fields. However, there still is a disadvantage of frequent mowing, and the grass grows poorly under shade and low temperature conditions. To develop a grass variety that circumvents these drawbacks, we cloned chitin-inducible gibberellins-responsive 1 (CIGR1) from Zoysia japonica Steud. The full-length of ZjCIGR1 was obtained by 5'/3' RACE PCR and phylogenetic tree showed that it belongs to the PAT1 group of GRAS protein family. The expression of ZjCIGR1 in wild-type zoysiagrass was confirmed in roots, meristems, leaves and flowers, especially high in the flowers. The transgenic zoysiagrass was confirmed by PCR using gene-specific primers, phosphinothricin-acetyl-transferase (PAT) strip test and Southern blot analysis. Resistance to abiotic stress was enhanced in the transformants and the plant heights were shorter compared to the wild-type. In addition, the transgenic Arabidopsis plant showed delayed aging and enhanced stress resistance. These results suggest that ZjCIGR1 plays a role in regulating environmental stress resistance and plant height.