The Functional Research On CbFZF

Chorispora bungeana is a kind of typical alpine subnival plant species, which suffer from low temperature, high altitude and strong UV light stress for a long period during the whole process of its growth. It shows highly cold tolerance without possessing any specific morphostructure by its physiological and molecular mechanisms reaction affect freezing tolerance in plants. Therefore, both abiotic and cold stress signaling can also be studied by using it as appropriate species.On basis of full-length of Chorispora bungeana finger zinc transcription factor, the pattern of CbFZF expression on transcription level and translation level under different stresses, including of cold, salt and abscisic acid(ABA). By transient expression of fluorescent fusion proteins in tobacco plants, CbFZF’s Subcellular localization was also investigate. Further more, CbFZF over experss transgenic Arabidopsis plants was got, which offers further study for the cold tolerance physiological function. The summary is shown as follows:1. The expression of CbFZF gene at transcription and translation level were changed under different stress treatment. The expression of CbFZF showed obvious increasing induced by4℃,0℃, which indicated CbFZF reacts on protecting Chorispora bungeana from cold infection. In additional, expression of CbFZF was also accumulated at different levels induced by ABA and NaCl. Therefore, CbFZF may have a complex mechanism to response different stresses(such as cold and salt).2. The cDNA fragment containing the CbFZF coding region without stop codon was amplified by RT-PCR. The open reading frame (ORF) of the gene was cloned into pEarlygate101—YFP, a plant overexpression vector fused with YFP. The result indicated that CbFZF was localized on cell membrane and nucleus after tobacco infiltration, it may maintain the stability of the cell membrane besides play the main function of the transcription factor. 3. The1.5-kb upstream sequence of the ATG translation start of AtFZF, which has82%homology with CbFZF, was amplified from genomic DNA, and sub cloned into the pBIB vector to produce a promoter-GUS fusion construct. Transformed wide type col Arabidopsis and obtained transgenic plants. The transgenic lines was used for GUS staining. the results indicated that AtFZF was expressed in root, stem and leaves, but didn’t in flower or silique. So the gene play an important role in growth and development of vegetative organs.Transgenic plants of CbFZF over expression and AtFZF:GUS were obtained.4. Conductivity and proline of AtFZF T-DNA mutant were measured, which indicated that both of them in mutant were increased compared with wild type under-4℃treatment, the results suggest the cold tolerance of mutant was decreased, so we presumed AtFZF was related with cold resistance of plants by stabling cell membrane, but whether the proline content is related with the gene need to be further investigated.In conclusion, CbFZF participates a variety of stress resistance pathways(cold, NaCl, ABA), it is not only a transcript factor, but also keep the stability of membrane. AtFZF can provide some references to study the function of CbFZF, such as regulate plant growth, protect cell membrane from low temperature. In a word, these obtained results and conclusions provide theoretical foundation for physiology and molecular biological research of the plant to response to abiotic stresses.