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Francoise Budar - One of the best experts on this subject based on the ideXlab platform.
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Brassica Ogu-INRA Cytoplasmic Male Sterility: An Example of Successful Plant Somatic Fusion for Hybrid Seed Production
Somatic Genome Manipulation, 2015Co-Authors: Georges Pelletier, Francoise BudarAbstract:This chapter retraces the history of using somatic hybridization to modify the Cytoplasmic Male Sterility (CMS)-inducing Ogura radish cytoplasm and its application in hybrid seed production for Brassica crops. First, we present hybrid seed production and the issues behind the introduction of the Ogura radish cytoplasm into Brassica crops. We then detail the procedures of the protoplast fusion experiments used to produce cybrids. Recombination between radish and Brassica mitochondrial genomes ultimately led to the creation of the Ogu-INRA system. Not only have cybrids contributed to hybrid seed production but also molecular analysis of cybrids helped identify the mitochondrial gene causing CMS, and contributed basic knowledge on plant mitochondrial gene expression. Furthermore, restoration of Male fertility is useful for some crops, and the Ogu-INRA system has also been used to identify restorer genes. The Ogu-INRA system is now widely used in agriculture.
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characterization of raphanus sativus pentatricopeptide repeat proteins encoded by the fertility restorer locus for ogura Cytoplasmic Male Sterility
The Plant Cell, 2008Co-Authors: Magalie Uyttewaal, Sophie Hiard, Alfred Martincanadell, Francoise Budar, Nadege Arnal, Martine Quadrado, Nathalie Vrielynck, Hassen Gherbi, Abdelhafid Bendahmane, Hakim MireauAbstract:Cytoplasmic Male Sterility is a maternally inherited trait in higher plants that prevents the production of functional pollen. Ogura Cytoplasmic Male Sterility in radish (Raphanus sativus) is regulated by the orf138 mitochondrial locus. Male fertility can be restored when orf138 accumulation is suppressed by the nuclear Rfo locus, which consists of three genes putatively encoding highly similar pentatricopeptide repeat proteins (PPR-A, -B, and -C). We produced transgenic rapeseed (Brassica napus) plants separately expressing PPR-A and PPR-B and demonstrated that both encoded proteins accumulated preferentially in the anthers of young flower buds. Immunodetection of ORF138 showed that, unlike PPR-B, PPR-A had no effect on the synthesis of the Sterility protein. Moreover, immunolocalization experiments indicated that complete elimination of ORF138 from the tapetum of anthers correlated with the restoration of fertility. Thus, the primary role of PPR-B in restoring fertility is to inhibit ORF138 synthesis in the tapetum of young anthers. In situ hybridization experiments confirmed, at the cellular level, that PPR-B has no effect on the accumulation of orf138 mRNA. Lastly, immunoprecipitation experiments demonstrated that PPR-B, but not PPR-A, is associated with the orf138 RNA in vivo, linking restoration activity with the ability to directly or indirectly interact with the orf138 RNA. Together, our data support a role for PPR-B in the translational regulation of orf138 mRNA.
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Cytoplasmic suppression of ogura Cytoplasmic Male Sterility in european natural populations of raphanus raphanistrum
Theoretical and Applied Genetics, 2007Co-Authors: Sandra Giancola, Sophie Chaillou, Sophie Hiard, Alfred Martincanadell, Georges Pelletier, Francoise BudarAbstract:The Ogura Cytoplasmic Male Sterility (CMS) of radish has been used for hybrid seed production in radish and Brassica crops. It is the only CMS system occurring in wild populations for which the gene responsible for Sterility and a restorer gene have been formally identified. In Japan, gynodioecious populations of radish carrying Ogura or an Ogura-related cytoplasm have been described. The occurrence of restorer genes for the Ogura CMS in wild radish (Raphanus raphanistrum) in France led us to search for the corresponding Male Sterility gene (orf138) in several natural populations in France, England and Lebanon. We detected the orf138 gene, by PCR, at low frequency, in three populations from France and one from Southern England. Further molecular characterization showed that these plants carried a cytoplasm closely related to the original Ogura cytoplasm, with a variant orf138 coding sequence, previously reported to be ancestral. We performed crosses with sterile and maintainer radish lines, to test the ability of this wild Ogura-related cytoplasm to induce Sterility. Surprisingly, the European Ogura-related cytoplasm did not cause Sterility. Northern blots and circular RT-PCR analyses showed that orf138 gene expression was impaired in these plants because of a novel cytoplasm-dependent transcript-processing site.
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unveiling the molecular arms race between two conflicting genomes in Cytoplasmic Male Sterility
Trends in Plant Science, 2004Co-Authors: Pascal Touzet, Francoise BudarAbstract:Cytoplasmic Male Sterility can be thought of as the product of a genetic conflict between two genomes that have different modes of inheritance. Male sterilizing factors, generally encoded by chimeric mitochondrial genes, can be down-regulated by specific nuclear restorer genes. The recent cloning of a restorer gene in rice and its comparison with restorer genes cloned in petunia and radish could be regarded as the beginning of a general molecular scenario in this peculiar arms race.
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ogura Cytoplasmic Male Sterility cms associated orf138 is translated into a mitochondrial membrane polypeptide in Male sterile brassica cybrids
Molecular Genetics and Genomics, 1994Co-Authors: Mathilde Grelon, Francoise Budar, Sandrine Bonhomme, Georges PelletierAbstract:Transcription of a putative mitochondrial gene (orf138) has previously been correlated with Ogura Cytoplasmic Male-Sterility (CMS) in rapeseed cybrids. In this paper, studies performed on a Brassica cybrid with a different organization of the orf138 locus confirm this association. We also show that mitochondria isolated from Male-sterile rapeseed plants synthesize a polypeptide of 19 kDa, which is absent in fertile revertants. Antibodies against a glutathione S-transferase-ORF138 fusion protein were raised to establish that this 19 kDa polypeptide is the product of orf138. The anti-ORF138 serum was used to demonstrate that the orf138 translation product occurs only in sterile cybrids and co-purifies with the mitochondrial membrane fraction.
Georges Pelletier - One of the best experts on this subject based on the ideXlab platform.
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Brassica Ogu-INRA Cytoplasmic Male Sterility: An Example of Successful Plant Somatic Fusion for Hybrid Seed Production
Somatic Genome Manipulation, 2015Co-Authors: Georges Pelletier, Francoise BudarAbstract:This chapter retraces the history of using somatic hybridization to modify the Cytoplasmic Male Sterility (CMS)-inducing Ogura radish cytoplasm and its application in hybrid seed production for Brassica crops. First, we present hybrid seed production and the issues behind the introduction of the Ogura radish cytoplasm into Brassica crops. We then detail the procedures of the protoplast fusion experiments used to produce cybrids. Recombination between radish and Brassica mitochondrial genomes ultimately led to the creation of the Ogu-INRA system. Not only have cybrids contributed to hybrid seed production but also molecular analysis of cybrids helped identify the mitochondrial gene causing CMS, and contributed basic knowledge on plant mitochondrial gene expression. Furthermore, restoration of Male fertility is useful for some crops, and the Ogu-INRA system has also been used to identify restorer genes. The Ogu-INRA system is now widely used in agriculture.
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Cytoplasmic suppression of ogura Cytoplasmic Male Sterility in european natural populations of raphanus raphanistrum
Theoretical and Applied Genetics, 2007Co-Authors: Sandra Giancola, Sophie Chaillou, Sophie Hiard, Alfred Martincanadell, Georges Pelletier, Francoise BudarAbstract:The Ogura Cytoplasmic Male Sterility (CMS) of radish has been used for hybrid seed production in radish and Brassica crops. It is the only CMS system occurring in wild populations for which the gene responsible for Sterility and a restorer gene have been formally identified. In Japan, gynodioecious populations of radish carrying Ogura or an Ogura-related cytoplasm have been described. The occurrence of restorer genes for the Ogura CMS in wild radish (Raphanus raphanistrum) in France led us to search for the corresponding Male Sterility gene (orf138) in several natural populations in France, England and Lebanon. We detected the orf138 gene, by PCR, at low frequency, in three populations from France and one from Southern England. Further molecular characterization showed that these plants carried a cytoplasm closely related to the original Ogura cytoplasm, with a variant orf138 coding sequence, previously reported to be ancestral. We performed crosses with sterile and maintainer radish lines, to test the ability of this wild Ogura-related cytoplasm to induce Sterility. Surprisingly, the European Ogura-related cytoplasm did not cause Sterility. Northern blots and circular RT-PCR analyses showed that orf138 gene expression was impaired in these plants because of a novel cytoplasm-dependent transcript-processing site.
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ogura Cytoplasmic Male Sterility cms associated orf138 is translated into a mitochondrial membrane polypeptide in Male sterile brassica cybrids
Molecular Genetics and Genomics, 1994Co-Authors: Mathilde Grelon, Francoise Budar, Sandrine Bonhomme, Georges PelletierAbstract:Transcription of a putative mitochondrial gene (orf138) has previously been correlated with Ogura Cytoplasmic Male-Sterility (CMS) in rapeseed cybrids. In this paper, studies performed on a Brassica cybrid with a different organization of the orf138 locus confirm this association. We also show that mitochondria isolated from Male-sterile rapeseed plants synthesize a polypeptide of 19 kDa, which is absent in fertile revertants. Antibodies against a glutathione S-transferase-ORF138 fusion protein were raised to establish that this 19 kDa polypeptide is the product of orf138. The anti-ORF138 serum was used to demonstrate that the orf138 translation product occurs only in sterile cybrids and co-purifies with the mitochondrial membrane fraction.
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The Cytoplasmic Male-Sterility (CMS) determinant of common bean is widespread in Phaseolus coccineus L. and Phaseolus vulgaris L.
Current Genetics, 1993Co-Authors: François Hervieu, Louis Charbonnier, Hubert Bannerot, Georges PelletierAbstract:To identify regions of the mitochondrial genome that potentially could specify Cytoplasmic Male Sterility (CMS) in Phaseolus coccineus (including P. polyanthus), and to define differences amongst P. coccineus lines, mitochondrial (mt)DNA restriction patterns and Southern blots of total DNA from sterile and fertile lines were analysed. By restriction endonuclease mapping we isolated a region which was specific to CMS lines flanking an F1-ATPase α-subunit (atpA) gene. DNA sequence analysis of this region showed 99.9% homology to the region previously isolated from P. vulgaris CMS Sprite. A high frequency of plants carrying the CMS-fragment was observed in a wild Phaseolus population, perhaps explaining the occurrence of inter- and intraspecific gene flow observed in the autogamous species P. vulgaris.
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sequence and transcript analysis of the nco2 5 ogura specific fragment correlated with Cytoplasmic Male Sterility in brassica cybrids
Molecular Genetics and Genomics, 1992Co-Authors: Sandrine Bonhomme, Francoise Budar, Dominique Lancelin, Ian Small, Mariechristine Defrance, Georges PelletierAbstract:Sequence analysis of the Ogura-specific mitochondria) DNA (mtDNA) fragment isolated previously from Brassica cybrids carrying Ogura Cytoplasmic Male Sterility (cms) revealed a tRNAfMet sequence, a putative 138 amino acid open reading frame (orf138), and a 158 amino acid ORF (orf158) previously observed in mitochondria) genomes from several other plant species. Transcription mapping showed that both ORFs are present on a 1.4 kb cms-specific transcript. The orf158 sequence is also transcribed in fertile plants on a different mRNA, and thus is unlikely to be related to cms. On the other hand, fertile revertant plants lack transcripts of the orf138 sequence, whose possible role in the mechanism of Ogura cms is discussed.
Kinya Toriyama - One of the best experts on this subject based on the ideXlab platform.
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whole mitochondrial genome sequencing and transcriptional analysis to uncover an rt102 type Cytoplasmic Male Sterility associated candidate gene derived from oryza rufipogon
Plant and Cell Physiology, 2013Co-Authors: Masayuki Okazaki, Keiji Motomura, Tomohiko Kazama, Hayato Murata, Kinya ToriyamaAbstract:Cytoplasmic Male Sterility (CMS) is a maternally inherited trait in which plants fail to produce functional pollen and is associated with the expression of a novel open reading frame (orf) gene encoded by the mitochondrial genome. An RT102A CMS line and an RT102C fertility restorer line were obtained by successive backcrossing between Oryza rufipogon W1125 and O. sativa Taichung 65. Using next-generation pyrosequencing, we determined whole-genome sequences of the mitochondria in RT102-CMS cytoplasm. To identify candidates for the CMS-associated gene in RT102 mitochondria, we screened the mitochondrial genome for the presence of specific orf genes that were chimeric or whose products carried predicted transmembrane domains. One of these orf genes, orf352, which showed different transcript sizes depending on whether the restorer of fertility (Rf) gene was present or not, was identified. The orf352 gene was co-transcribed with the ribosomal protein gene rpl5, and the 2.8 kb rpl5-orf352 transcripts were processed into 2.6 kb transcripts with a cleavage at the inside of the orf352 coding region in the presence of the Rf gene. The orf352 gene is an excellent candidate for the CMS-associated gene for RT102-CMS.
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whole genomic sequencing of rt98 mitochondria derived from oryza rufipogon and northern blot analysis to uncover a Cytoplasmic Male Sterility associated gene
Plant and Cell Physiology, 2013Co-Authors: Keisuke Igarashi, Tomohiko Kazama, Keiji Motomura, Kinya ToriyamaAbstract:Cytoplasmic Male Sterility (CMS) is a maternally inherited trait resulting in the failure to produce functional pollen and is often observed when an alien cytoplasm is transferred into a cultivated species. An RT98A CMS line and an RT98C fertility restorer line were obtained by successive backcrossing between Oryza rufipogon W1109 and Oryza sativa cultivar Taichung 65. To uncover the CMS-associated mitochondrial genes, we determined the complete sequence of the RT98-CMS mitochondrial genome using next-generation pyrosequencing, and searched new open reading frames (orfs) absent in a reported mitochondrial genome of O. sativa Nipponbare. Then, six candidates were selected for the CMS-associated genes based on the criteria in which they were chimeric in structure or encoded a peptide with transmembrane domains. One of the candidates, orf113, showed different transcript sizes between RT98A and RT98C on Northern blot analysis. The orf113 gene was shown to be co-transcribed with atp4 and cox3 encoding ATP synthase F0 subunit 4 and Cyt c oxidase subunit 3, respectively, and their transcripts were distinctly processed in the presence of a fertility restorer gene. Our results indicate that orf113 is a CMS-associated gene of RT98-CMS.
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the fertility restorer gene rf2 for lead rice type Cytoplasmic Male Sterility of rice encodes a mitochondrial glycine rich protein
Plant Journal, 2011Co-Authors: Etsuko Itabashi, Tomohiko Kazama, Sota Fujii, Natsuko Iwata, Kinya ToriyamaAbstract:Summary Cytoplasmic Male Sterility (CMS) is associated with a mitochondrial mutation that causes an inability to produce fertile pollen. The fertility of CMS plants is restored in the presence of a nuclear-encoded fertility restorer (Rf) gene. In Lead Rice-type CMS, discovered in the indica variety ‘Lead Rice’, fertility of the CMS plant is restored by the single nuclear-encoded gene Rf2 in a gametophytic manner. We performed map-based cloning of Rf2, and proved that it encodes a protein consisting of 152 amino acids with a glycine-rich domain. Expression of Rf2 mRNA was detected in developing and mature anthers. An RF2–GFP fusion was shown to be targeted to mitochondria. Replacement of isoleucine by threonine at amino acid 78 of the RF2 protein was considered to be the cause of functional loss in the rf2 allele. As Rf2 does not encode a pentatricopeptide repeat protein, unlike a majority of previously identified Rf genes, the data from this study provide new insights into the mechanism for restoring fertility in CMS.
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Characterization of Cytoplasmic Male Sterility of rice with Lead Rice cytoplasm in comparison with that with Chinsurah Boro II cytoplasm.
Plant Cell Reports, 2008Co-Authors: Etsuko Itabashi, Tomohiko Kazama, Kinya ToriyamaAbstract:Rice with LD-type Cytoplasmic Male Sterility (CMS) possesses the cytoplasm of ‘Lead Rice’ and its fertility is recovered by a nuclear fertility restorer gene Rf1. Rf1 promotes processing of a CMS-associated mitochondrial RNA of atp6–orf79, which consists of atp6 and orf79, in BT-CMS with the cytoplasm of ‘Chinsurah Boro II’. In this study, we found that LD-cytoplasm contained a sequence variant of orf79 downstream of atp6. Northern blot analysis showed that atp6–orf79 RNA of LD-cytoplasm was co-transcribed and was processed in the presence of Rf1 in the same manner as in BT-cytoplasm. Western blot analysis showed that the ORF79 peptide did not accumulate in an LD-CMS line, while ORF79 accumulated in a BT-CMS line and was diminished by Rf1. These results suggest that accumulation of ORF79 is not the cause of CMS in LD-cytoplasm and the mechanism of Male-Sterility induction/fertility restoration in LD-CMS is different from that in BT-CMS.
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Genome barriers between nuclei and mitochondria exemplified by Cytoplasmic Male Sterility
Plant and Cell Physiology, 2008Co-Authors: Sota Fujii, Kinya ToriyamaAbstract:Since plants retain genomes of an extremely large size in mitochondria (200-2,400 kb), and mitochondrial protein complexes are comprised of chimeric structures of nuclear- and mitochondrial-encoded subunits, coordination of gene expression between the nuclei and mitochondria is indispensable for sound plant development. It has been well documented that the nucleus regulates organelle gene expression. This regulation is called anterograde regulation. On the other hand, recent studies have demonstrated that signals emitted from organelles regulate nuclear gene expression. This process is known as retrograde signaling. Incompatibility caused by genome barriers between a nucleus and foreign mitochondria destines the fate of pollen to be dead in Cytoplasmic Male Sterility (CMS), and studies of CMS confirm that pollen fertility is associated with anterograde/retrograde signaling. This review summarizes the current perspectives in CMS and fertility restoration, mainly from the viewpoint of anterograde/retrograde signaling.
Hakim Mireau - One of the best experts on this subject based on the ideXlab platform.
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the propensity of pentatricopeptide repeat genes to evolve into restorers of Cytoplasmic Male Sterility
Frontiers in Plant Science, 2016Co-Authors: Lydiane Gaborieau, Gregory G Brown, Hakim MireauAbstract:Cytoplasmic Male Sterility (CMS) is a widespread phenotype in plants, which present a defect in the production of functional pollen. The Male sterilizing factors usually consist of unusual genes or open reading frames (ORFs) encoded by the mitochondrial genome. CMS can be suppressed by specific nuclear genes called restorers of fertility (Rfs). In the majority of cases, Rf genes produce proteins that act directly on the CMS conferring mitochondrial transcripts by binding them specifically and promoting processing events. In this review, we explore the wide array of mechanisms guiding fertility restoration. PPR proteins represent the most frequent protein class among identified Rfs and they exhibit ideal characteristics to evolve into restorer of fertility when the mechanism of restoration implies a post-transcriptional action. Here, we review the literature that highlights those characteristics and help explain why PPR proteins are ideal for the roles they play as restorers of fertility.
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characterization of raphanus sativus pentatricopeptide repeat proteins encoded by the fertility restorer locus for ogura Cytoplasmic Male Sterility
The Plant Cell, 2008Co-Authors: Magalie Uyttewaal, Sophie Hiard, Alfred Martincanadell, Francoise Budar, Nadege Arnal, Martine Quadrado, Nathalie Vrielynck, Hassen Gherbi, Abdelhafid Bendahmane, Hakim MireauAbstract:Cytoplasmic Male Sterility is a maternally inherited trait in higher plants that prevents the production of functional pollen. Ogura Cytoplasmic Male Sterility in radish (Raphanus sativus) is regulated by the orf138 mitochondrial locus. Male fertility can be restored when orf138 accumulation is suppressed by the nuclear Rfo locus, which consists of three genes putatively encoding highly similar pentatricopeptide repeat proteins (PPR-A, -B, and -C). We produced transgenic rapeseed (Brassica napus) plants separately expressing PPR-A and PPR-B and demonstrated that both encoded proteins accumulated preferentially in the anthers of young flower buds. Immunodetection of ORF138 showed that, unlike PPR-B, PPR-A had no effect on the synthesis of the Sterility protein. Moreover, immunolocalization experiments indicated that complete elimination of ORF138 from the tapetum of anthers correlated with the restoration of fertility. Thus, the primary role of PPR-B in restoring fertility is to inhibit ORF138 synthesis in the tapetum of young anthers. In situ hybridization experiments confirmed, at the cellular level, that PPR-B has no effect on the accumulation of orf138 mRNA. Lastly, immunoprecipitation experiments demonstrated that PPR-B, but not PPR-A, is associated with the orf138 RNA in vivo, linking restoration activity with the ability to directly or indirectly interact with the orf138 RNA. Together, our data support a role for PPR-B in the translational regulation of orf138 mRNA.
Tomohiko Kubo - One of the best experts on this subject based on the ideXlab platform.
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mitochondrial dna phylogeny of cultivated and wild beets relationships among Cytoplasmic Male Sterility inducing and nonsterilizing cytoplasms
Genetics, 2007Co-Authors: S Nishizawa, Tetsuo Mikami, Tomohiko KuboAbstract:Cytoplasmic Male Sterility (CMS), the maternally inherited failure to produce functional pollen, has been used in the breeding of sugar beet (Beta vulgaris ssp. vulgaris). At least three different sources of CMS can be distinguished from one another as well as from normal fertile cytoplasm by polymorphisms in their mitochondrial genomes. Here we analyzed 50 accessions of cultivated and wild beets to investigate the phylogenetic relationships among Male-Sterility-inducing and normal cytoplasms. The haplotypes were characterized by the nucleotide sequence of the mitochondrial cox2-cox1 spacer region and mitochondrial minisatellite loci. The results indicated that (1) a normal cytoplasm line, cv. TK81-O, was situated at the major core node of the haplotype network, and (2) the three sterilizing cytoplasms in question derived independently from the core haplotype. The evolutionary pathway was investigated by physical mapping study of the mitochondrial genome of a wild beet (B. vulgaris ssp. orientalis) accession BGRC56777 which shared the same mitochondrial haplotype with TK81-O, but was not identical to TK81-O for the RFLP profiles of mitochondrial DNA. Interestingly, three sets of inverted repeated sequences appeared to have been involved in a series of recombination events during the course of evolution between the BGRC56777 and the TK81-O mitochondrial genomes.
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molecular mapping of a fertility restorer gene for owen Cytoplasmic Male Sterility in sugar beet
Theoretical and Applied Genetics, 2005Co-Authors: Eiki Hagihara, N Itchoda, Y Habu, Shigeru Iida, Tetsuo Mikami, Tomohiko KuboAbstract:We report here the molecular mapping of a fertility restorer gene (named Rf1) for Owen Cytoplasmic Male Sterility in sugar beet. Eight AFLP and two RAPD markers, tightly linked to the Rf1 locus, were identified using bulked segregant analysis. Three AFLP markers, mAFEM972, mAFEM976 and mAFEM985, were found to co-segregate with the Rf1 allele in our mapping populations. With the help of RFLP markers, previously mapped on the sugar beet genome, we showed that Rf1 is positioned in the terminal region of linkage group Kiel III/Koeln IV. This map location agrees well with that found for the restorer gene X, which suggests that the Rf1 locus corresponds to the X locus. The availability of the molecular markers will facilitate the selection of maintainer–pollinator lines in breeding program and provide the foundation for map-based cloning of the Rf1 gene.
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the 5 leader sequence of sugar beet mitochondrial atp6 encodes a novel polypeptide that is characteristic of owen Cytoplasmic Male Sterility
Molecular Genetics and Genomics, 2005Co-Authors: Masayuki P Yamamoto, Tomohiko Kubo, Tetsuo MikamiAbstract:Cytoplasmic Male Sterility (CMS) is a mitochondrially encoded trait, which is characterized by a failure of plants to produce viable pollen. We have investigated the protein profile of mitochondria from sugar beet plants with normal (fertile) or CMS cytoplasm, and observed that a 35-kDa polypeptide is expressed in Owen CMS plants but not in normal plants. The variant 35-kDa polypeptide was found in CMS mitochondria placed in five different nuclear backgrounds. Interestingly, this polypeptide proved to be antigenically related to a 387-codon ORF (preSatp6) that is fused in-frame with the downstream atp6. The presequence extension of the atp6 ORF is commonly found in higher plants, but whether or not it is normally expressed has hitherto remained unclear. Our study is thus the first to demonstrate that the atp6 presequence is actually translated in mitochondria. We also observed that preSATP6 is a mitochondrial membrane protein that assembles into a homogeneous 200-kDa protein complex. In organello translation experiments in the presence of protease inhibitors showed a reduction in the abundance of mature preSATP6 with time, suggesting that the mature preSATP6 may be derived by proteolytic processing of a translation product of the preSatp6/Satp6 ORF.
