Expression Analysis Of The Sexual Reproduction Organ Specific Expression Genes In Medicago Truncatula And Identification Of The Functional Characteristics Of The Alfalfa MsGME Gene

The expression of genes specific to floral organ and seed is important during the sexual reproduction in Medicago truncatula. Screening of the genes specifically expressed in M. truncatula flowers and seed, and comparing the expression patterns their orthologous homologous genes among different model plants can provide novel insights into the functions of these genes in controlling the sexual reproduction in M. truncatula. In the study, we found that the orthologous homolog gene of alfalfa MsGME in Medicago truncatula was highly expressed in pods and seeds. The full-length cDNA sequences of MsGME gene was amplified from alfalfa and transformed into Arabidopsis and obtained resistance of transgenic plants. Further details are as below:1. We screen 97 genes specifically expressed in M. truncatula floral organs. By comparing the orthologous homolog genes of floral organ with other species, the result showed that the gene expression patterns and gene functions were not identical. Further analysis of the results showed that the discrepancy between the homologous gene expression patterns may be caused by the different characteristics of the cis-elements in the promoter regions of the homologous genes.2. The comparison revealed that 605 genes are specifically expressed in M. truncatula seeds. We compared the expression patterns of seed-specific genes from each species with their homologues in the other three species, and found that the degree of variation in the expression patterns of homologous genes was low among closely related species but higher among more distantly related ones.3. The MsGME gene was amplified from alfalfa and highly expressed in pods and seeds and nucleotide sequence analysis revealed that MsGME contains a 1,146-bp ORF that encodes a 381-amino acid polypeptide.4. Expression patterns analysis revealed that the expression level of MsGME gene was raised by acid, drought and salt tolerance.5. The MsGME gene was transformed into Arabidopsis and enhanced abiotic stress tolerance in transgenic Arabidopsis by increasing ascorbate accumulation.