Functional Analysis Of TFⅢA-Type Zinc Finger Protein Gene ZFP252 From Rice (Oryza Sativa L.)

Plant growth and crop productivity are largely affected by environmental stresses such as drought, high salinity and low temperature. To date, many stress-related genes have been isolated and characterized from various plant species. These genes may encode products either directly protecting plant cells from abotic stresses or regulating expression of other genes to enhance plant tolerance to abiotic stresses.Rice (Oryza sativa L.) is not only one of the most important food crops in the world, but also a model plant for research on molecular biology in monocots. It was previously found that a TFâ…¢A-type zinc-finger protein gene ZFP252 from rice could be significantly up-regulated in rice seedlings under salt or drought stress.It was generated several sense or antisense ZFP252 transgenic rice plants driven by the cauliflower mosaic virus (CaMV) 35S promoter. The expression level of ZFP252 was significantly higher in sense ZFP252 transgenic plants than that in non-transgenic plants and was hardly detected in antisense ZFP252 transgenic plants by both semi-quantitative RT-PCR and quantitative real-time PCR.There were no significant changes in morphological or agronomic traits among ZFP252 transgenic plants and non-transgenic plants. The stress assays showed that overexpression of ZFP252 in rice significantly enhanced the tolerance of transgenic plants to salt and drought stress. After 10 d of salt or drought treatment, their relative electrolyte leakage from antisense ZFP252 transgenic plants and non-transgenic plants were higher than that from sense ZFP252 transgenic plants.The contents of proline and soluble sugars in sense ZFP252 transgenic lines were much more increased than those in antisense ZFP252 transgenic plants and non-transgenic plants under salt and drought stress. Furthermore, it was found that the transcripts of several stress-related genes including OsDREB1A, Oslea3, OsP5CS and OsProT were accumulated more in sense ZFP252 transgenic plants under stress treatments by quantitative real-time PCR.It was concluded that overexpression of ZFP252 may contribute to accumulate compatible osmolytes, such as free proline, soluble sugars and LEA proteins that function as osmoprotectants, by regulating expression of stress-related genes in rice under salt and drought stress conditions.