S-RNase-mediated gametophytic self-incompatibility (GSI) is controlled by a multiallelic S-locus at which two separate genes, the female (pistil) and male (pollen) specificity determinants, are tightly linked. T...S-RNase-mediated gametophytic self-incompatibility (GSI) is controlled by a multiallelic S-locus at which two separate genes, the female (pistil) and male (pollen) specificity determinants, are tightly linked. This review described both the identification of pollen specific F-box genes, SLF/SFBs, in Antirrhinum, Petunia and Prunus species and the demonstration of SLF/SFB as pollen determinant together with their functions in GSI response. Recent studies of how the pollen determinant functions in pollination reaction revealed that pollen determinant interacted with S-RNases in a non-allele-specific manner. It targeted all of the non-self S-RNases for ubiquitination through a functional SCF complex and subsequent degradation via 26S proteasome pathway in compatible reaction. It allows pollen tube to reach into the embryo sac and to finish double fertilization. In incompatible response, the intact self S-RNases were left to function as a cytotoxin that degrades self-pollen tube RNA, resulting in the cessation of pollen tube growth.展开更多
[Objective] The aim was to breed the indica-compatible japonica lines(ICJLs).[Method] The indica-compatibility of 5 candidate ICJLs were tested based on the pollen fertility and spikelet fertility of F1 hybrids with...[Objective] The aim was to breed the indica-compatible japonica lines(ICJLs).[Method] The indica-compatibility of 5 candidate ICJLs were tested based on the pollen fertility and spikelet fertility of F1 hybrids with 6 indica testers,6 japonica testers and 6 middle testers.[Result] Candidate ICJL G2123,G2417,G2410 and G3005 were grouped into the exceptionally(Specific)indica-compatible lines based on their high indica-compatibility and low japonica-compatibility.Candidate ICJL G2615 was grouped into the non-compatible lines on their low indica-compatibility and low japonica-compatibility.[Conclusion] The testers,fertility identification standards,test methods of pollen fertility and spikelet fertility were discussed when the compatibility of CICJLs was tested.The reason of the indica-compatibility in G2417 was analyzed.展开更多
This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragment...This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragments encoding BR/HLH/LZ structure of Myc and Myn proteins were cloned in frame into pGEX-2T vec-tor respectively Fusion GST-Myc and GST-Myn synthe-sized in E.coli hosts showed affinity to CACGTG E-boxDNA and subsequently interacted with genomic fragments prepared through whole-genome-PCR. A PCR-assisted procedure which combines protein-DNA interaction and affinity chromatography was designed to enrich Myc/Myn bound DNA. At least two genomic DNA fragments ob- tained exhibit specifical binding capacity to Myc/Myn complex but not to GST alone. Significance of the work and of the technique itself as well as identification of the DNAs are discussed.展开更多
基金This work was supported by grants from Three Founda-tions of Hunan Province (00JZY2155) and International Cooperation Project
文摘S-RNase-mediated gametophytic self-incompatibility (GSI) is controlled by a multiallelic S-locus at which two separate genes, the female (pistil) and male (pollen) specificity determinants, are tightly linked. This review described both the identification of pollen specific F-box genes, SLF/SFBs, in Antirrhinum, Petunia and Prunus species and the demonstration of SLF/SFB as pollen determinant together with their functions in GSI response. Recent studies of how the pollen determinant functions in pollination reaction revealed that pollen determinant interacted with S-RNases in a non-allele-specific manner. It targeted all of the non-self S-RNases for ubiquitination through a functional SCF complex and subsequent degradation via 26S proteasome pathway in compatible reaction. It allows pollen tube to reach into the embryo sac and to finish double fertilization. In incompatible response, the intact self S-RNases were left to function as a cytotoxin that degrades self-pollen tube RNA, resulting in the cessation of pollen tube growth.
基金Supported by National High Technology Development Plan Financial Program(101-Z16-02-01,2001AA211181)~~
文摘[Objective] The aim was to breed the indica-compatible japonica lines(ICJLs).[Method] The indica-compatibility of 5 candidate ICJLs were tested based on the pollen fertility and spikelet fertility of F1 hybrids with 6 indica testers,6 japonica testers and 6 middle testers.[Result] Candidate ICJL G2123,G2417,G2410 and G3005 were grouped into the exceptionally(Specific)indica-compatible lines based on their high indica-compatibility and low japonica-compatibility.Candidate ICJL G2615 was grouped into the non-compatible lines on their low indica-compatibility and low japonica-compatibility.[Conclusion] The testers,fertility identification standards,test methods of pollen fertility and spikelet fertility were discussed when the compatibility of CICJLs was tested.The reason of the indica-compatibility in G2417 was analyzed.
文摘This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragments encoding BR/HLH/LZ structure of Myc and Myn proteins were cloned in frame into pGEX-2T vec-tor respectively Fusion GST-Myc and GST-Myn synthe-sized in E.coli hosts showed affinity to CACGTG E-boxDNA and subsequently interacted with genomic fragments prepared through whole-genome-PCR. A PCR-assisted procedure which combines protein-DNA interaction and affinity chromatography was designed to enrich Myc/Myn bound DNA. At least two genomic DNA fragments ob- tained exhibit specifical binding capacity to Myc/Myn complex but not to GST alone. Significance of the work and of the technique itself as well as identification of the DNAs are discussed.