Molecular Response Analysis To High Temperature Stresses In Celery

Temperature is one of the major environmental factor for plant growth and crop yield.Since the 1980s,the global warming caused by the greenhouse effect became very obviously,and high temperature poses more serious threat to plants.High temperature will harm the development of plants,and enhancing the thermotolerance of celery is essential.Celery is a herb belonging to the Apiaceae and is susceptible to high temperature injury.The celery plants grown in the artificial climate chamber were used as materials to find the regulation mechanism under high temperature stress,respectively from proteomics,transcriptomics,and genomics to provide theoretical basis for celery breeding.Main results are as follows:1.We compared the proteomes from the leaves of 2-month-old ’Ventura’ that were treated with different temperatures(4℃ 25℃ and 38℃)for 1 day.By using 2-DE protein analysis,78 protein spots were identified in the leaves of celery.A total of 17 proteins greatly responded to high temperature,including:chlorophyll a/b binding protein type,hypothetical protein,RuBisCO,chaperonin 60,Fe2+ transport protein 1,ATP synthase,and fructose-bisphosphate aldolase,etc.2.AgHSFs belong to HSF gene family factor,which plays key roles in protecting plants from heat stress.Based on the data of the celery transcriptome sequences,we identified 20 AgHSFs genes by using bioinformatics methods.These AgHSFs genes encoded 163～527 amino acids.The predicted molecular weight of AgHSFs varied from 19.29 to 58.14 kD,and pI values varied from 4.97 to 8.44.Sequence alignments showed that all AgHSFs had specific DNA binding domain(DBD).Phylogenetic analysis showed 20 AtHSFs from Arabidopsis thaliana and 20 AgHSFs from celery were classified into three major classes(class A,B,and C).Class A was further subdivided into 9 subclasses,and class B was further subdivided into 4 subclasses.Class A contained 12 AgHSFs,Class B contained 6 AgHSFs,Class C contained 2 AgHSFs.AgHSFs had tissue-specific and cultivar-specific expression.AgHSFs also greatly respond to different temperature treatments.3.Agvip1 gene was respectively cloned from three celery cultivars(’Liuhe Huangxinqin’,’Jinnan Shiqin’,and ’Ventura’).Agvip1 contained a 768 bp open reading frame encoded with 255 amino acid residues.The predicted molecular weight of AgVIP1 was 27.2 kD,and pI value was 5.3.The phylogenetic analysis showed VIP 1-like proteins from Solanum lycopersicum and Solanum tuberosum in Solanaceae had the shortest evolutionary relationship with AgVIP1 from celery.Quantitative real-time PCR showed that Agvip1 gene had tissue-specific expression.The expression of Agvip1 had great differences under many abiotic and metal ions stresses.In conclusion,temperature stress could induce obvious expressional changes of a lot genes and proteins.By the interactions of related proteins,AgHSFs could protect plants from high temperature stress.