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Wood formation is a complex biological process strictly regulated by the gene through molecular breeding technology to improved wood quality, first-depth understanding of the molecular mechanisms of wood formation process, the study of the key genes that control wood formation and its interaction mechanism to achieve destination molecular breeding design, and ultimately achieve the purpose of regulation of wood formation, improved wood quality. Calmodulin (Calmodulin, CaM) is a kind of the most widely distributed and the most important function of the calcium-dependent regulatory protein, as Ca2 of intracellular receptors affect the Ca2 + concentration, and by activating a series of target enzymes and non-enzyme protein, regulation Ca2 caused a series of physiological and biochemical reactions. PtCaM cambium site in Populus \In order to study the relationship between the PtCaM tree growth and development, this study, cloned in Populus tomentosa PtCaM, its overexpression in poplar cambial activity and secondary vascular tissue development by genetic engineering techniques. The main findings of this paper are as follows: (1) the use of the RT-PCR method, to form a layer of tissue preparation of cDNA isolated PtCaM cDNA from Populus tomentosa, sequencing and sequence analysis. The analysis showed that the cloned PtCaM cDNA fragment of a total length of 642bp, gene contains an internal size of the full open reading frame of 447 bp - length encoding length of 149 amino acid residues of the protein polypeptide. PtCaM carrots, Populus trichocarpa, Arabidopsis, maize and wheat CaM highly homologous, homology was 100%, 99%, 99%, 98%, 97%. (2) In order to study the impact of PtCaM cambial activity and secondary vascular tissue formation, build PtCaM excess expression vector, Agrobacterium-mediated transformation of Poplar 84K transgenic plants. Real-time quantitative PCR, PtCaM overexpression in transgenic plants, up to about 11.9 times the control plants. Phenotype observed and variance analysis found higher on average than the control plants 9cm PtCaM justice transgenic plants seedling height, ground diameter 0.59 cm on average than the control plants, mature leaf morphology change significantly compared with control plants, and the differences were highly significant. Of the the poplar stem cross-section slices observed the PtCaM justice turn transgenic plants xylem region of cell layers increased significantly, but basically no change in cell volume. In addition, the phloem and the cell layers of the region of the forming layer is almost no change. These results indicate that overexpression of PtCaM lead cambium cell division to upregulate the proliferation of the cells of the xylem region, and in turn had an impact on the growth and development of plants.
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