Cloning And Expression Analysis Of Genes Related To Nitrogen Metabolism From Eichhornia Crassipes

The glutamine synthetase(GS) and ammonium transporter(AMT) has an important role in the process of plant nitrogen metabolis,and They have a great impact on the growth and reproduction of plants.In order to explore the molecular mechanism of Eichhornia crassipes ammonium eutrophic water absorption. Using degenerate primers clone three kinds of Eichhornia crassipes ammonium transporter gene fragment (EcAMT1, EcAMT2 and EcAMT3), and the expression of these three genes in the different forms of nitrogen conditions were studied, compared to nitrogen deficiency, ammonium and nitrate nitrogen conditions, EcAMTl gene expression is suppressed, and the expression of EcAMT2 and EcAMT3 are contrary, nitrate and ammonium condition but can promote gene expression. Description express different types of ammonium transporter gene in response to environmental factors vary.So the expression of different types of ammonium transporter gene are different in response to environmental factors.The three full-length GS1 are cloned using PCR technology, and then connect to PYES2.finally transformed into the haploid of Y25454. (this mutant was unable to grow where proline, ammonium ions was as the sole source of nitrogen in the case of YNB medium growth). After identification of Saccharomyces cerevisiae mutants complementary functional tests proved that the mutant strain of yeast transformed GS gene can grow under the 1%concentration of proline or less than 5mM concentration of ammonium ion. And it grows better and faster than the wild type BY4741, so the GS gene has high ammonium transport function.Extract the glutamine synthetase from the Eichhornia crassipes that incubated at different intensities of light,different types of inhibitors and different concentrations of sucrose, and detect and analysis the changes of activity, then explore the lighting, inhibitors, sucrose to the glutamine synthetase activity from the roots and leaves of the Eichhornia crassipes. The results showed that different light intensity has a certain influence on the glutamine synthetase activity of the Eichhornia crassipes. The GS activity was significantly increased in the light of the first day, that in a short time, the light has improvement effect on the activity of GS, and with the increase of light intentsity, the activity of GS increased,but But after the light intensity reaches a certain intensity, with increasing irradiation time, GS activity decreased. Sucrose had no significant effect on the water hyacinth root glutamine synthetase activity. Methionine sulfoxide imino-generation (MSX) had inhibition on water hyacinth roots and leaves of GS activity, but as time increases, GS activity has shown a downward trend. Glutamine (Gln) also had inhibition on GS enzyme activity. Adding MSX and Gln in experiment made GS substantially no activity, the inhibition more stronger.