Study Of Carbonic Anhydrases From Populus Simonii×P. Nigra

The carbonic anhydrases (or carbonate dehydratases) form a family of enzymes that catalyze the rapid interconversion of carbon dioxide and water to bicarbonate and protons (or vice versa), a reversible reaction that occurs rather slowly in the absence of a catalyst. The active site of most carbonic anhydrases contains a zinc ion.They are widely present in plants,which play an important role in the photosynthesis of higher plants.In order to imporove the carbon fixation and photosynthesis of plants,we study six carbonic anhydrase genes from different part of Populus simonii×P.nigra by RT-PCR. Main results are as below:1.Based on cDNA library of poplar in EBI, six full-length genes of carbonic anhydrase family were successfully cloned from Populus and were taken bioinformatics analysis. The genes were named PsnCA1, PsnCA2, PsnCA3, PsnCA4,PsnCA5and PsnCA6. PsnCA1, PsnCA3and PsnCA5are from the α-CA family and PsnCA4and PsnCA6are from the β-CA family,when PsnCA2is from LbH super family. Multiple compared with amino acid sequences of relevant genes of other species,we drew the phylogenetic trees. And the signal peptide structure, hydrophobicity and secondary structure were predicted.2.The experiments of6genes have the tissue-specific. All of the genes were the most in the leaves rather than in roots and stems except for PsnCA6. And PsnCA1was the most notable gene,when the PsnCA3was the second one and PsnCA5was the least one. The experiment of PsnCA1was1.7times than PsnCA3,and226times than PsnCA5.3.The samples of Populus simonii×P.nigra were respectively took6hours、12hours、24hours and24hours dark treatment. And we took the roots、leaves and stems for experiments by RT-PCR. The result of RT-PCR show that PsnCA1had the highest expression level in leaves,which is0.005times under48hour treatmeng than the CK group. And the PsnCA3was similar to PsnCA1, but not as PsnCA1significantly. The experiments of other genes had no signifianctly changes.4.For further analyse the function of PsnCAl, we structure the vector of ps1300-CA1,which takes the fluorescent.