The Physiological Role Of Fe In Rice And Expression Of NRAMP Gene

The molecular physiology of iron nutrition in plant was supported by 973 grant. The relationship between the differential display of functional genomics and the difference of morphoresis and physiology were researched in rice as material. The purpose is that the pathway of iron nutrition molecular physiology will be drawn. The rice seedlings were cultured under iron-deficiency, ferric citrate, Fecl3 and EDTA-Fe respectively. Different morphoresis were observed and different physiological indexs(such as root activity , ATPase activity , photosythetic pigment and plant hormones etc.) were obtained in my thesis work. Morphoresis observation showed that the rice seedlings grew best with ferric citrate, next was FeCl3 the third was EDTA-Fe( II) Different physiological index also was similar to the result of morphoresis. It was so surprised that the seedlings cultured in FeCl3 was almost as good as that cultured with ferric citrate and EDTA-Fe( II). FeCl3 was simulated as Fe-deficient in soil. These results inferred the PS can be inducible under the FeCl3 condition as Fe -deficient in rice, but iron-deficiency in culturing solution can not be.Recently, NRAMP1 gene related with Fe and Mn transporting in wheat roots was cloned into pMD18-T vector in our laboratory. NRAMP1 is about 600bp in length and is said to be the possible mechanism of iron absorption-endocytotic mechanism whose research has been supported by the NNSFC grant. My work is to research the expression of NRAMP1 in transcription level and try to obtain the full-cDNA by using RACE method. The result of northern hybridization showed that Nrampl can be transcripted in the roots and leaves of wheat treated with EDTA-Fe2+ and Fe-free. Southern hybridization showed that Nrampl presents in wheat and rice with only one copy.