Endosperm Expression Of The Genomic Fragment Separation And Phosphorus Metabolism Of Species Differences,

Transgenic technology is wildly used in rice improvement. The foreign gene can express directional by linkage of foreign gene and rice promoter, and it could reduce the probability of foreign gene silence. The objective of this study was to identify genes that no expression in rice endosperm by cDNA array analysis. The cDNA array was made based on Minghui 63 normalized cDNA library. RNA samples isolated from different rice organs were used to synthesize cDNA as probes for screening the cDNA arrays. By analysis the expression result, several clones were identified that no expression in rice endosperm. After Northern assay and sequence analysis, cDNA clone EI#44P17 encoding photosystem II 10KDa protein precursor was used to screen 58N BAG library. The 6.2 kb fragment was found to be homolog of EI#44P17 in positive BAG clone 119H12 with further analysis. We have sequenced the whole BAC119H12 with Shotgun Method to find the candidate promoter. Sequence analysis with GENESCAN shows that it has the ORF of photosystem II lOKDa protein precursor, and the result of GeneFinder shows the same result.The object of this study is to identify the genes that are related to uptake or assimilation of phosphorus by analysis expression profiles in two rice cultivars. The two kinds of rice cultivars that have different sensitive in low-phosphorus were treated in two different solutions from 3-leaf-stage, one containing normal concentrations of phosphorous and the other containing one thirtieth of normal phosphorus respectively. mRNA was extracted from the shoots and roots at 1hr, 6hr, 12hr, 1day and 7days were used to synthesize probes for cDNA microarray hybridization. The fluorescently labeled probes were hybridized with the microarray of 5760 unique genes from the Minghui 63 normalized cDNA library and five subtractive cDNA libraries. The mRNA of the stressed and the control were reverse-transcribed and labeled with Cy3 and Cy5 respectively. The ratio of the thresholds were determined with statistical analysis the yellow-dots experiment, they are 1.78 and 0.55. Gene expression in response to low-phosphorus stressed wasinvestigated with microarray containing 5760 unique cDNA sequences. The number of this kind of genes is different in different cultivars, different organs and different period of time after low-phosphorus stresses. The significantly increased or decreased expressions were found and Northern-blot of part of clones showed the same results. Sequence analysis revealed the differentially expressed sequences encoded all kinds of proteins and enzymes that relate to all fields of plant physiology and biochemistry. Some of the genes identified in this study have been reported to be related to Pi-deprivation. It is easy to find the difference in gene expression after low-phosphorus stresses between the two rice cultivars: first, Zhongzao18 responses more drastically than Lagrue; second, Zhongzao18 has the ability to product organic acid continually in one period while Lagrue has not; last, Pi-deprivation can deduce abnormal in nitrogen metabolism, this abnormal in Lagrue is stronger than in Zhongzao18. This difference may lead that Zhongzao18 gowns better than Lagrue when Pi-deprivation in soil.