Cloning and Characterization of a Second form of the Rice Adenine Phosphoribosyl Transferase Gene (OsAPT2) and its Association with TGMS

• Published in: Plant molecular biology 2006-02, Vol.60 (3), p.365-376
• Main Authors: Zhou, C.J, Li, J, Zou, J.C, Liang, F.S, Ye, C.J, Jin, D.M, Weng, M.L, Wang, B
• Format: Article
• Language: English
• Subjects: Adenine - chemistry; adenine phosphoribosyltransferase; Adenine Phosphoribosyltransferase - chemistry; Adenine Phosphoribosyltransferase - genetics; Adenosine - chemistry; Adenosine Monophosphate - metabolism; Alleles; Amino Acid Sequence; amino acid sequences; Amino acids; Blotting, Northern; Cloning; Cloning, Molecular; complementary DNA; Computational Biology - methods; DNA Primers - chemistry; DNA, Complementary - metabolism; Down-Regulation; Enzymes; Exons; Fertility; gene expression regulation; Gene Expression Regulation, Plant; genes; Genes, Plant; Genetic Vectors; Genomics; Homozygote; Hot Temperature; inflorescences; Introns; Light; Male sterility; messenger RNA; Models, Genetic; Molecular Sequence Data; nucleotide sequences; Nucleotides - chemistry; Oligonucleotides, Antisense - chemistry; Oryza - enzymology; Oryza - genetics; Oryza sativa; Phenotype; plant fertility; Plant Leaves - metabolism; Plant Physiological Phenomena; Pollen; Pollen - metabolism; pollen fertility; pollen germination; Polymerase Chain Reaction; Protein Structure, Secondary; Reverse Transcriptase Polymerase Chain Reaction; Rice; RNA, Messenger - metabolism; Sequence Homology, Amino Acid; Temperature; thermo-sensitive gene male sterility; Transgenes; Transgenic plants
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/s11103-005-4208-5

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'.