| Fructose-1,6-bisphosphate aldolase(FBA)is a key plant enzyme involved in glycolysis,gluconeogenesis,and Calvin cycle.It plays significant roles in biotic and abiotic stress responses,and also in regulating growth and development processes.FBA genes have been extensively studied in many other species,but little is known about the gene family in wheat,and the prominent function of the FBA gene has not been characterized.In this study,we identified and cloned the FBA gene family in wheat and carried out bioinformatics,gene expression,protein methylation and genetic transformation and other research,came to a few conclusions:(1)A total of 21 Ta FBA isoenzymes genes were identified,characterized,and categorized into three groups: class I chloroplast/plastid FBA,class I cytosol FBA and class II chloroplast/plastid FBA.Through the predication of online database and the genomic PCR of Chinese Spring nulli-tetrasomic lines,we have confirmed the chromosomal location of these genes in 12 chromosomes of four homologous groups.(2)The sequence analysis revealed the high identity of allelic genes and the origins of different genes.Genomic structure analysis indicated that these genes could be clustered into six subgroups.Many putative environment stimulus-responsive cis-elements have been identified in 1500 bp regions of Ta FBA gene promoters,and the most abundant one was Light-regulated Elements(LREs).(3)The phylogenetic tree was constructed about 245 FBA proteins from different organisms,suggesting independent evolution pathway of class I and class II group,and 10 plant FBA proteins including three wheat FBAs could be classified into Type B of class II.Although earlier researches suggested that class II FBAs only occurred in prokaryote and fungi,our study indicated that there were a few class II Cp FBAs in wheat and its relative species.In addition,although both class I and class II FBAs have an aldolase-type TIM barrel domain,class I of Ta FBA was predicated to be tetramers and class II be dimmers.(4)The gene expression analysis based on microarray and transcriptome data suggested the distinct role of Ta FBAs in different tissues and developmental stages.Finally,differential expression of 21 Ta FBA genes was analyzed in light/dark conditions and a few abiotic stresses,and the q PCR results implied the significance of Ta FBA genes in stress-related responses.The class I cytosol Ta FBA,especially Ta FBA10/12/18 and Ta FBA13/16,and class II Ta FBA genes could play important role in responses to abiotic stresses.(5)The levels of lysine triethylation of chloroplast FBA protein in three wheat cultivars Chinese Spring,Aibian 1 and Albinism line were detected by Western-blot.The methylation level of FBA protein of chloroplast of Aibian 1 and Chinese Spring was not affected by the decrease of temperature.The methylation level of FBA protein in the leaves of Albinism line was significantly higher than that of the Aibian 1 and Chinese Spring at room temperature,and the methylation level of the FBA protein of Albinism line was decreased rapidly at low temperature.(6)The expression level of Cp FBA gene in transgenic wheat was studied by semiquantitative PCR.It was found that the relative expression level of Cp FBA gene in the green transgenic plants was higher than that of white transgenic plants. |
