Limits...
A Missense Mutation in the Zinc Finger Domain of OsCESA7 Deleteriously Affects Cellulose Biosynthesis and Plant Growth in Rice.

Wang D, Qin Y, Fang J, Yuan S, Peng L, Zhao J, Li X - PLoS ONE (2016)

Bottom Line: The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant.The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm.These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.

View Article: PubMed Central - PubMed

Affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.

ABSTRACT
Rice is a model plant species for the study of cellulose biosynthesis. We isolated a mutant, S1-24, from ethyl methanesulfonate (EMS)-treated plants of the japonica rice cultivar, Nipponbare. The mutant exhibited brittle culms and other pleiotropic phenotypes such as dwarfism and partial sterility. The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant. Map-based gene cloning and a complementation assay showed that phenotypes of the S1-24 mutant were caused by a recessive point mutation in the OsCESA7 gene, which encodes cellulose synthase A subunit 7. The missense mutation changed the highly conserved C40 to Y in the zinc finger domain. The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm. These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.

No MeSH data available.


Related in: MedlinePlus

Map-based cloning of the gene responsible for the S1-24 phenotype.(A) The location of the gene locus was narrowed to an approximately 154-kb region on chromosome 10. Vertical lines represent the positions of molecular markers and the number of recombinants. (B) Seventeen predicted ORFs within the fine mapping region. Green, ORFs with known biochemical functions; Yellow, ORFs encoding expressed hypothetical proteins; Black, ORFs encoding transposons. (C) Genomic structure of OsCESA7. Boxes indicate exons. The mutation site is located in the first exon. (D) Protein structure of OsCESA7 including the RING-type zinc finger indicated in blue; two Asp (D) residues, the DXD, Q/RXXRW motifs indicated in red; and eight transmembrane domains indicated in yellow. Tos17 insertion sites in the NC0259 and ND8759 mutants allelic to the S1-24 mutant are indicated by arrows. (E) Alignment of zinc finger motif template and the corresponding OsCESA7 region. The site of the mutation C40 is highly conserved.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4836682&req=5

pone.0153993.g005: Map-based cloning of the gene responsible for the S1-24 phenotype.(A) The location of the gene locus was narrowed to an approximately 154-kb region on chromosome 10. Vertical lines represent the positions of molecular markers and the number of recombinants. (B) Seventeen predicted ORFs within the fine mapping region. Green, ORFs with known biochemical functions; Yellow, ORFs encoding expressed hypothetical proteins; Black, ORFs encoding transposons. (C) Genomic structure of OsCESA7. Boxes indicate exons. The mutation site is located in the first exon. (D) Protein structure of OsCESA7 including the RING-type zinc finger indicated in blue; two Asp (D) residues, the DXD, Q/RXXRW motifs indicated in red; and eight transmembrane domains indicated in yellow. Tos17 insertion sites in the NC0259 and ND8759 mutants allelic to the S1-24 mutant are indicated by arrows. (E) Alignment of zinc finger motif template and the corresponding OsCESA7 region. The site of the mutation C40 is highly conserved.

Mentions: To determine the genetic basis of the S1-24 mutation and clone the mutated gene, an F2 population was generated by crossing S1-24 with Dular, a polymorphic indica variety. In the F2 population, normal and brittle culm phenotypes were exhibited by 4,934 and 1,550 individual plants, respectively, in accordance with a Mendelian segregation ratio of 3:1 (χ2 = 2.10 < χ20.05 = 3.84), indicating that the brittle culm phenotype is controlled by a single recessive gene. A map-based cloning approach was used to isolate the causative gene. For primary mapping, 100 F2 mutant individuals were used to locate the target gene between two indel markers, Ha2 and Ha9, on the long arm of chromosome 10. Six new indel markers and 1,400 F2 individuals with the brittle culm phenotype were used for fine mapping. The gene was localized within a 154-kb region between indel markers Ha6 and Ha7 (Fig 5A, S1 Table). This region was covered by overlapping the BAC clones Ac022457.8 and Ac026815.8.


A Missense Mutation in the Zinc Finger Domain of OsCESA7 Deleteriously Affects Cellulose Biosynthesis and Plant Growth in Rice.

Wang D, Qin Y, Fang J, Yuan S, Peng L, Zhao J, Li X - PLoS ONE (2016)

Map-based cloning of the gene responsible for the S1-24 phenotype.(A) The location of the gene locus was narrowed to an approximately 154-kb region on chromosome 10. Vertical lines represent the positions of molecular markers and the number of recombinants. (B) Seventeen predicted ORFs within the fine mapping region. Green, ORFs with known biochemical functions; Yellow, ORFs encoding expressed hypothetical proteins; Black, ORFs encoding transposons. (C) Genomic structure of OsCESA7. Boxes indicate exons. The mutation site is located in the first exon. (D) Protein structure of OsCESA7 including the RING-type zinc finger indicated in blue; two Asp (D) residues, the DXD, Q/RXXRW motifs indicated in red; and eight transmembrane domains indicated in yellow. Tos17 insertion sites in the NC0259 and ND8759 mutants allelic to the S1-24 mutant are indicated by arrows. (E) Alignment of zinc finger motif template and the corresponding OsCESA7 region. The site of the mutation C40 is highly conserved.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4836682&req=5

pone.0153993.g005: Map-based cloning of the gene responsible for the S1-24 phenotype.(A) The location of the gene locus was narrowed to an approximately 154-kb region on chromosome 10. Vertical lines represent the positions of molecular markers and the number of recombinants. (B) Seventeen predicted ORFs within the fine mapping region. Green, ORFs with known biochemical functions; Yellow, ORFs encoding expressed hypothetical proteins; Black, ORFs encoding transposons. (C) Genomic structure of OsCESA7. Boxes indicate exons. The mutation site is located in the first exon. (D) Protein structure of OsCESA7 including the RING-type zinc finger indicated in blue; two Asp (D) residues, the DXD, Q/RXXRW motifs indicated in red; and eight transmembrane domains indicated in yellow. Tos17 insertion sites in the NC0259 and ND8759 mutants allelic to the S1-24 mutant are indicated by arrows. (E) Alignment of zinc finger motif template and the corresponding OsCESA7 region. The site of the mutation C40 is highly conserved.
Mentions: To determine the genetic basis of the S1-24 mutation and clone the mutated gene, an F2 population was generated by crossing S1-24 with Dular, a polymorphic indica variety. In the F2 population, normal and brittle culm phenotypes were exhibited by 4,934 and 1,550 individual plants, respectively, in accordance with a Mendelian segregation ratio of 3:1 (χ2 = 2.10 < χ20.05 = 3.84), indicating that the brittle culm phenotype is controlled by a single recessive gene. A map-based cloning approach was used to isolate the causative gene. For primary mapping, 100 F2 mutant individuals were used to locate the target gene between two indel markers, Ha2 and Ha9, on the long arm of chromosome 10. Six new indel markers and 1,400 F2 individuals with the brittle culm phenotype were used for fine mapping. The gene was localized within a 154-kb region between indel markers Ha6 and Ha7 (Fig 5A, S1 Table). This region was covered by overlapping the BAC clones Ac022457.8 and Ac026815.8.

Bottom Line: The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant.The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm.These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.

View Article: PubMed Central - PubMed

Affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.

ABSTRACT
Rice is a model plant species for the study of cellulose biosynthesis. We isolated a mutant, S1-24, from ethyl methanesulfonate (EMS)-treated plants of the japonica rice cultivar, Nipponbare. The mutant exhibited brittle culms and other pleiotropic phenotypes such as dwarfism and partial sterility. The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant. Map-based gene cloning and a complementation assay showed that phenotypes of the S1-24 mutant were caused by a recessive point mutation in the OsCESA7 gene, which encodes cellulose synthase A subunit 7. The missense mutation changed the highly conserved C40 to Y in the zinc finger domain. The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm. These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.

No MeSH data available.


Related in: MedlinePlus