Identification Of Induced Root Proteins Under Iron-deficiency And Molecular Cloning Of MxSAMS In Malus Xiaojinensis

The iron-deficiency stressed protein expression pattern in apple (Malus xiaojinensis Cheng et Jiang) root was studied. Two proteins of SAM family induced in root by Fe treatment were characterized according to their PMF. MxSAMS gene encoding one of the two proteins was cloned. Southern blot shows there is only one single copy of MxSAMS gene in the genome. Northern blot proved it is Fe-deficiency induced.No new protein appeared in root under OuM and 4μM Fe treatments. One 40KDa leaf protein was upregulated in 10 days under OuM Fe treatment. But it was downregulated in 2-8days under 4uM Fe treatment. The other 42KDa leaf protein treated by 4uM Fe was induced in 4-8 days. It indicated that the leaf proteins expression pattern changed under OuM and 4uM Fe treatment.No new protein appeared and no protein disappeared under Fe treatments. Two proteins were identified by PMF. Both of them belong to SAM family, but their PMF were different.They probably play different roles in plant. The other three proteins induced by Fe treatment had not been identified, which might be unknown.proteins.The MxSAMS gene was cloned, which is 1479bp in length and has an ORF of 1176bp encoding 392 amino acids. The pI is 5.58 and the molecule weight is 42.99KDa. It is an acidic protein. The Southern blot experiment was performed, which indicated that MxSAMS has only one single copy in the genome of Malus xiaojinensis. The expression pattern under Fe treatment was analyzed by Northern blot. It showed that MxSAMS gene was induced from 2 to 8 days.