Bioinformatic Analysis And Expression Study Of AtPAP6 Homologous Gene In Brassica Napus

Phosphorus is one of the essential nutrients for plant growth and development, and lack of available phosphorus have an important effect on the metabolism of plant, yield and quality traits. Apases is conserved in the plant, which is capable of catalyzing the hydrolysis anhydridrs and phosphorie acid esters into inorganic Pi under mild acid environment, and to meet the metabolic needs of plants. PAP is changed from pink to purpler result from a charge transfer transition by a tyrosine residue coordinating a ferric ion, which constitutes the largest group of Apases. PAP secretion of plants will increase by phosphorus starvation, which activate extracellular organic phosphorus into inorganic phosphorus. Rapeseed is one of the most important oil crops in China and very sensitive to phosphorus deficiency. Therefore, it can improve the yield and quality of rape by improving the efficiency of phosphorus uptake and utilization.Bioinformatics as a new discipline, which has become an important part of current life science, and is widely used in various fields of life science research. The huge amounts of data generated in biological research can be used to analyze and predict quickly by using bioinformatics and all kinds of biological databases. Bioinformatics analyze and predict the information of the gene, the function and structure of the protein, which can screen, identify, predict and discover the significance of the gene.Utilized the results of rapeseed genome sequencing work. BnaA03g59200 D and BnaC07g51090 D carried on the homologous comparison by blastp, and constructed the phylogenetic tree, then conducted the related biological information analysis, and compared with the AtPAP6. On this basis, investigating the expression and relevance of the two genes responsed to phosphate starvation induced in the seedling leaves(SL) and root(SR) of of Brassica napus ‘Dingyouza-4’ by real-time PCR. The main research conclusion as follows:1. 15 protein sequences with high homology were selected by blastp omologous comparison. The coverage of AtPAP6 was 98%, the identity was 87%, and the homology reach the highest. Then used MEGA6.06 for conducting multiple sequence alignment and constructing phylogenetic tree, found BnaA03g59200 D and BnaC07g51090 D orthologous to AtPAP6.2. Predicted by ProtParam, AtPAP6,BnaA03g59200 D and BnaC07g51090 D molecular weight was 52.83 KDa,52.19 KD and 52.21 KDa respectively; PI was 6.39, 6.22 and 6.22 respectively; instability coefficient was 42.44, 43.04 and 41.65 respectively, they all were unstable protein. Detected by ProtScale, all proteins were hydrophilicity.3. Predicted by SignalP 4.1 Server, all proteins had a signal peptide. MultiLoc/TargetLoc predicted that all proteins probably located in lysosome, potential coefficient of AtPAP6 was 0.88, these two proteins were also 0.9.4. Analyzed by SOPMA, the main structural elements of secondary structure were random coils and strands, followed by alpha helices and beta turns. Predicted by NetPhos 2.0 Server, AtPAP6 had 18 serine phosphorylation sites, 8 tyrosine phosphorylation sites and 6 threonine phosphorylation sites, these two proteins was 19, 10 and 7 respectively. TMpred Server predicted that all proteins had two transmembrane structures. COILS Server predicted that AtPAP6 had 9 coiled coil structures, these two proteins all were 8.5. CDD detected that all proteins belonged to metal phosphatase superfamily and contained 7 metal ion binding sites. Predicted by SWISS-MODEL, the tertiary structures of BnaA03g59200 D and BnaC07g51090 D proteins were very similar to AtPAP6. PROSITE predicted that AtPAP6 had 6 specific functional sites, and these two proteins all were 5.6. Based on the comparison of the two proteins and AtPAP6 above-mentioned, investigating the expression and relevance of the two genes responsed to phosphate starvation after 0 h, 24 h, 2 d, 4 d and 6d and 3 d after Pi resupply, respectively in the SL and SR of Brassica napus ‘Dingyouza-4’by real-time PCR. The results showed that these two genes were induced by phosphate starvation and expressed in the SL and SR, expression of the genes increased gradually between 0h-6d and reached the maximal level 6d after phosphorus starvation. After theer days of Pi-resupply, the genes expression decreased to basal expression level. These results indicated that these two genes may be related to the absorption of Pi and induced by phosphorus starvation.