ABSTRACT
A rice gene, OsAPT2, which encodes a putative adenine phosphoribosyl transferase (APRT), was cloned and characterized. Analysis of the cDNA and genomic sequences revealed seven exons and six introns in the OsAPT2. The deduced amino acid sequence of OsAPT2 is highly homologous to those of previously isolated APRTs. RT-PCR analysis indicated that the OsAPT2 transcript in the young panicles of 'Annong S-1' is down-regulated at 29 degrees C, the critical temperature for induction of 'Annong S-1' fertility conversion. Since the panicle is likely the thermo-sensitive organ at the early stages of pollen fertility alternation, the observed heat-induced change in the OsAPT2 expression pattern in young panicles may mediate, at least in part, thermo-sensitive genic male sterility (TGMS) in 'Annong S-1'. An antisense strategy was used to suppress the expression of the OsAPT2 homolog in Arabidopsis, and the obtained homozygous transgenic plants contained lower AMP content, displayed lower pollen germination rates and exhibited some abnormalities in leaf phenotypes and flowering timing. These data suggest that OsAPT2 is likely to be involved in TGMS in the rice line 'Annong S-1'.
Subject(s)
Adenine Phosphoribosyltransferase/genetics , Oryza/genetics , Adenine/chemistry , Adenine Phosphoribosyltransferase/chemistry , Adenosine/chemistry , Adenosine Monophosphate/metabolism , Alleles , Amino Acid Sequence , Blotting, Northern , Cloning, Molecular , Computational Biology/methods , DNA Primers/chemistry , DNA, Complementary/metabolism , Down-Regulation , Exons , Gene Expression Regulation, Plant , Genes, Plant , Genetic Vectors , Homozygote , Hot Temperature , Introns , Light , Models, Genetic , Molecular Sequence Data , Nucleotides/chemistry , Oligonucleotides, Antisense/chemistry , Oryza/enzymology , Phenotype , Plant Leaves/metabolism , Plant Physiological Phenomena , Pollen/metabolism , Polymerase Chain Reaction , Protein Structure, Secondary , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid , Temperature , TransgenesABSTRACT
beta-1,3-glucanase(BG2) is one of the pathogensis-related-proteins(PR). Study of these proteins and their related genes is one of the hot points in plant genetic engineering of disease resistance for a long time. In this research, specific primers were designed with the enzyme cleavage site of Spe I in its forward one and Not I site in the backward according to the BG2 gene sequence. Using this pair of primers, BG2 gene, which was contained in the plasmid of pRTL2, was amplified and confirmed by sequencing the amplified fragment inserted into T-easy vector. The positive clone containing BG2 gene was digested with the enzymes of Spe I/Not I and then BG2 gene was inserted into the Xba I/Not I sites of super expression binary vector pATC940. The reconstructed expression vector named as pATCBG2 was introduced into the wheat of Longfumai10 and Longfumai3 (Triticum aestivum L. em. Thell) through the particle gun transformation method. The Kanamysin resistant (Km') transformants were obtained. PCR, Dot-blotting and PCR-Southern hybridization analysis showed that the BG2 gene was integrated into the genome of wheat. Result of pathogen inoculation assay on the transgenic plants showed that the transgenic plants had a higher resistant disease score of 1-2 grade than the control.
Subject(s)
Genetic Vectors/genetics , Glucan 1,3-beta-Glucosidase/genetics , Triticum/genetics , Ascomycota/growth & development , Blotting, Southern , Cloning, Molecular/methods , DNA, Plant/genetics , DNA, Plant/metabolism , Deoxyribonuclease EcoRI/metabolism , Deoxyribonuclease HindIII/metabolism , Immunity, Innate/genetics , Plant Diseases/genetics , Plant Diseases/microbiology , Plants, Genetically Modified , Transformation, Genetic , Triticum/microbiologyABSTRACT
Southern corn rust (SCR) is a destructive disease in maize. The inbred line Qi319 is highly resistant to southern corn rust. The inheritance of resistance to southern rust in Qi319 was investigated. Five F1 hybrids were derived from Qi319 crossed with five susceptible inbred lines respectively. The F2 generations were produced by F1 self-pollinated and BC1 F1 generations were abtained by backcrossing F1 with the susceptible parents. Inoculation of the P1, P2, F1 s and 10 individuals of F2, BC1 F1 were completed with the southern corn rust pathogen and showed that all of the 10 F1 s were resistant, the all 5 F2 populations segregated in a ratio of 3R:1S, and all of the 5 BC1 F1 populations segregated in a ratio of 1R:1S. Therefore, it is considered that Qi319 carries one dominant gene for resistance to southern corn rust.
