WRKY proteins are transcriptional regulators involved in plant responses to biotic and abiotic stresses, metabolisms, and developmental processes. In the present study, we isolated a WRKY cDNA, OsWRKY89 from a rice cD...WRKY proteins are transcriptional regulators involved in plant responses to biotic and abiotic stresses, metabolisms, and developmental processes. In the present study, we isolated a WRKY cDNA, OsWRKY89 from a rice cDNA library. The deduced polypeptide contains 263 amino acid residues with a potential leucine zipper structure in its N-terminus, sharing low identity with other known WRKY members. OsWRKY89 and three deletion derivatives from its N-terminal were expressed in high levels in Escherichia coli as a C-terminally six-histidine-tagged fusion protein, and purified by employing one-step affinity chromatography on a Ni-NTA column. The recombinant OsWRKY89 protein was found to bind specially to sequences harboring W box cis elements by using electrophoretic mobility shift assays. This binding activity was decreased significantly by deletion of the leucine zipper-like structure in the N-terminal of Os- WRKY89. Using a yeast two-hybrid assay system, we found that the leucine zipper motif of OsWRKY89 was involved in the protein-protein interaction. Further deletion to remove partial WRKY domain abolished completely the interaction between the expressed protein and the W boxes, indicating that the WRKY domain is essential to the DNA-binding. These data strongly suggest that the leucine zipper-like motif of OsWRKY89 plays a significant role in the protein-protein and DNA-protein interactions.展开更多
Using a degenerated primer and a T-primer, a MADS-box gene, M79,was amplified by RT-PCR from rice fluorescence at meiosis stage and then cloned. Sequence analysis shows that M79 shares 98.2% homology with OsMADS7 at D...Using a degenerated primer and a T-primer, a MADS-box gene, M79,was amplified by RT-PCR from rice fluorescence at meiosis stage and then cloned. Sequence analysis shows that M79 shares 98.2% homology with OsMADS7 at DNA level while only 92% at the amino acid level. The transcript of M79 possesses five different polyadenylation sites. Only a single copy of M79 gene has been found in rice genome, which is located on chromosome 8. M79 is expressed specifically in flower organs, from pre-meiosis stage through pollen maturation. Ectopic expression of M79 in T0 and T1 transgenic rice results in early-flowering, implying that M79 is involved in controlling the flowering time. In the same time, M79 may be involved in controlling the branching process to make more flower buds.展开更多
A rice mutant, G069, characteristic of few tiller numbers, was found in anther culture progeny from the F1 hybrid between an indica-japonica cross, Gui630×02428. The mutant has another two major features: delayed...A rice mutant, G069, characteristic of few tiller numbers, was found in anther culture progeny from the F1 hybrid between an indica-japonica cross, Gui630×02428. The mutant has another two major features: delayed tillering development and yellowing apex and margin on the mature leaves. As a donor parent, G069 was further backcrossed with the recurrent parent, 02428, for two turns to develop a BC2F2 population. Genetic analysis in the BC2F2 population showed that the traits of few-tillering and yellowing apex and margin on the mature leaves were controlled by one recessive gene. A pool of equally mixed genomic DNA, from few-tillering individual plants in BC2F2, was constructed to screen polymorphism with simple sequence repeat (SSR) markers in comparison with the 02428 genome. One SSR marker and three restriction fragment length polymorphism (RFLP) markers were found possibly linked with the recessive gene. By using these markers, the gene of few-tillering was mapped on chromosome 2 between RFLP marker C424 and S13984 with a genetic distance of 2.4 cM and 0.6 cM, respectively. The gene is designated ft1.展开更多
基金This work was supported by the State Basic Research and Development Plan(G200001 6203)the National Natural Science Foundation of China(Grant Nos.30370139&30471122).
文摘WRKY proteins are transcriptional regulators involved in plant responses to biotic and abiotic stresses, metabolisms, and developmental processes. In the present study, we isolated a WRKY cDNA, OsWRKY89 from a rice cDNA library. The deduced polypeptide contains 263 amino acid residues with a potential leucine zipper structure in its N-terminus, sharing low identity with other known WRKY members. OsWRKY89 and three deletion derivatives from its N-terminal were expressed in high levels in Escherichia coli as a C-terminally six-histidine-tagged fusion protein, and purified by employing one-step affinity chromatography on a Ni-NTA column. The recombinant OsWRKY89 protein was found to bind specially to sequences harboring W box cis elements by using electrophoretic mobility shift assays. This binding activity was decreased significantly by deletion of the leucine zipper-like structure in the N-terminal of Os- WRKY89. Using a yeast two-hybrid assay system, we found that the leucine zipper motif of OsWRKY89 was involved in the protein-protein interaction. Further deletion to remove partial WRKY domain abolished completely the interaction between the expressed protein and the W boxes, indicating that the WRKY domain is essential to the DNA-binding. These data strongly suggest that the leucine zipper-like motif of OsWRKY89 plays a significant role in the protein-protein and DNA-protein interactions.
基金the National Hi-Tech Program, National Natural Science Foundation of China(Grant No. 39670169), Research Initiative Fund for Returned Scientists from Ministry of Education and Major State Basic Research Programmes of People's Republic of China: Functio
文摘Using a degenerated primer and a T-primer, a MADS-box gene, M79,was amplified by RT-PCR from rice fluorescence at meiosis stage and then cloned. Sequence analysis shows that M79 shares 98.2% homology with OsMADS7 at DNA level while only 92% at the amino acid level. The transcript of M79 possesses five different polyadenylation sites. Only a single copy of M79 gene has been found in rice genome, which is located on chromosome 8. M79 is expressed specifically in flower organs, from pre-meiosis stage through pollen maturation. Ectopic expression of M79 in T0 and T1 transgenic rice results in early-flowering, implying that M79 is involved in controlling the flowering time. In the same time, M79 may be involved in controlling the branching process to make more flower buds.
文摘A rice mutant, G069, characteristic of few tiller numbers, was found in anther culture progeny from the F1 hybrid between an indica-japonica cross, Gui630×02428. The mutant has another two major features: delayed tillering development and yellowing apex and margin on the mature leaves. As a donor parent, G069 was further backcrossed with the recurrent parent, 02428, for two turns to develop a BC2F2 population. Genetic analysis in the BC2F2 population showed that the traits of few-tillering and yellowing apex and margin on the mature leaves were controlled by one recessive gene. A pool of equally mixed genomic DNA, from few-tillering individual plants in BC2F2, was constructed to screen polymorphism with simple sequence repeat (SSR) markers in comparison with the 02428 genome. One SSR marker and three restriction fragment length polymorphism (RFLP) markers were found possibly linked with the recessive gene. By using these markers, the gene of few-tillering was mapped on chromosome 2 between RFLP marker C424 and S13984 with a genetic distance of 2.4 cM and 0.6 cM, respectively. The gene is designated ft1.
