CDNA-cloning And Expression Analysis Of Phosphate Stress Induced Purple Acid Phosphatase Genes And Transcription Factor Genes From Seeding Wheat

Phosphorus (P) is one of the essential macronutrients for plant growth and development. It isnot only the component of plant cells, but also plays an important role on cell metabolism andsignal transduction. Although P is quite abundant in soil, the concentration of available P isextremely low. Therefore, screening P efficiency wheat genotypes and using the key genesresponsive to low P stress will be a necessary approach to achieve sustainable use of P resourcesby modern molecular biological technology.Our experiments on seedling wheat under P stress were carried out in the hydroponic cultureindoors. The comparative genomics method was used to screen P stress-induced purple acidphosphatase (PAP) and transcription factor(TF) genes. In the meantime,the expression patternwere primarily analyzed by semi-quantitative RT-PCR in this study. The main results were asfollows:1. cDNA-cloning of P stress-induced PAP genes and expression analysisUsing homology cloning, we have gained one new cDNA-cloning of PAP gene, named:TaPAP-like1. The results about homologous gene of known AtPAP1 and TaPAP-like1 bysemi-quantitative RT-PCR suggest: As well as AtPAP12, TaPAP-like 1 belongs to P stress-inducedenhancement expression type. This means there exists gene transcription products in cells under P+conditions and the gene transcription products enhanced significantly with P stress time increased;Induction of the homologous gene of AK334325.1 and TaPAP-like 1 transcripts was observed inthe shoots and roots. TaPAP-like1 was induced continuously, while expression level ofAK334325.1 had decreased after 7d P stress with P stress time increased. This may imply thatwheat plants probably active other rescue mechanisms to adapt to P stress.2. cDNA-cloning of P stress-induced TF-like genes and expression analysisUsing homology cloning, we gained three new cDNA-cloning of TF-like genes, named:TaPAP-like1. Semi-quantitative RT-PCR suggest:Induction of TaMYB-like1 was observed in theshoots, but the inductive effect did not appear in the roots; The original reference gene OsPHR2showed a similar constitutive expression pattern in all tissues with higher expression level in rootsand leaves.The steady expression of OsPHR2 in both roots and shoots was not very responsive to Pi deprivation. Induction of TaMYB-like2 transcripts was observed in the shoots under 4d P stress,but it was not obvious in the roots; On the contrary, the original reference gene At3g25790 wasstrongly induced by P deprivation.The response of TaMYB-like3 to P stress was not obvious in theshoots and roots; While the induction original reference gene AtMYB62 transcripts was observedonly in the leaves during Pi starvation. The expression patterns of P stress-induced TF-like genesby comparative genomics in our study was not the same as the original reference gene, furtherresearch on the functions of these genes may offer clues to reveal P regulation network of wheat.