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Isoflavones belong to the class of flavonoid compounds, which are important secondary metabolites that play a crucial role in plant development and defense. Acetyl-CoA carboxylase (ACCase) is a biotin-dependent enzyme that catalyzes the conversion of Acetyl-CoA into Malonyl-CoA in plants. It is a key enzyme in fatty acid synthesis and also catalyzes the production of various secondary metabolites. However, information on the ACC gene family in the soybean (Glycine max L. Merr.) genome and the specific members involved in isoflavone biosynthesis is still lacking. In this study, we identified 20 ACC family genes (GmACCs) from the soybean genome and further characterized their evolutionary relationships and expression patterns. Phylogenetic analysis showed that the GmACCs could be divided into five groups, and the gene structures within the same groups were highly conserved, indicating that they had similar functions. The GmACCs were randomly distributed across 12 chromosomes, and collinearity analysis suggested that many GmACCs originated from tandem and segmental duplications, with these genes being under purifying selection. In addition, gene expression pattern analysis indicated that there was functional divergence among GmACCs in different tissues. The GmACCs reached their peak expression levels during the early or middle stages of seed development. Based on the transcriptome and isoflavone content data, a weighted gene co-expression network was constructed, and three candidate genes (Glyma.06G105900, Glyma.13G363500, and Glyma.13G057400) that may positively regulate isoflavone content were identified. These results provide valuable information for the further functional characterization and application of GmACCs in isoflavone biosynthesis in soybean. [ABSTRACT FROM AUTHOR]

Isoflavones belong to the class of flavonoid compounds, which are important secondary metabolites that play a crucial role in plant development and defense. Acetyl-CoA carboxylase (ACCase) is a biotin-dependent enzyme that catalyzes the conversion of Acetyl-CoA into Malonyl-CoA in plants. It is a key enzyme in fatty acid synthesis and also catalyzes the production of various secondary metabolites. However, information on the ACC gene family in the soybean (Glycine max L. Merr.) genome and the specific members involved in isoflavone biosynthesis is still lacking. In this study, we identified 20 ACC family genes (GmACCs) from the soybean genome and further characterized their evolutionary relationships and expression patterns. Phylogenetic analysis showed that the GmACCs could be divided into five groups, and the gene structures within the same groups were highly conserved, indicating that they had similar functions. The GmACCs were randomly distributed across 12 chromosomes, and collinearity analysis suggested that many GmACCs originated from tandem and segmental duplications, with these genes being under purifying selection. In addition, gene expression pattern analysis indicated that there was functional divergence among GmACCs in different tissues. The GmACCs reached their peak expression levels during the early or middle stages of seed development. Based on the transcriptome and isoflavone content data, a weighted gene co-expression network was constructed, and three candidate genes (Glyma.06G105900, Glyma.13G363500, and Glyma.13G057400) that may positively regulate isoflavone content were identified. These results provide valuable information for the further functional characterization and application of GmACCs in isoflavone biosynthesis in soybean.

Asia minor bluegrass (Polypogon fugax) is a common and problematic weed throughout China. P. fugax that is often controlled by acetyl-CoA carboxylase (ACCase) inhibitors in canola fields. Herein, we confirmed a P. fugax population (R) showing resistance to all ACCase inhibitors tested with resistance indexes ranging from 5.4–18.4. We further investigated the resistance mechanisms of this R population. Molecular analyses revealed that an amino acid mutation (Asp-2078-Gly) was present in the R population by comparing ACCase gene sequences of the sensitive population (S). In addition, differences in susceptibility between the R and S population were unlikely to be related to herbicide metabolism. Furthermore, a new derived cleaved amplified polymorphic sequence (dCAPS) method was developed for detecting the Asp-2078-Gly mutation in P. fugax efficiently. We found that 93.75% of plants in the R population carried the Asp-2078-Gly mutation, and all the herbicide-resistant phenotype of this R population is inseparable from this mutation. This is the first report of cross resistance to ACCase inhibitors conferred by the Asp-2078-Gly target-site mutation in P. fugax. The research suggested the urgent need to improve the diversity of weed management practices to prevent the widespread evolution of herbicide resistance in P. fugax in China. [ABSTRACT FROM AUTHOR]

Asia minor bluegrass (Polypogon fugax) is a common and problematic weed throughout China. P. fugax that is often controlled by acetyl-CoA carboxylase (ACCase) inhibitors in canola fields. Herein, we confirmed a P. fugax population (R) showing resistance to all ACCase inhibitors tested with resistance indexes ranging from 5.4–18.4. We further investigated the resistance mechanisms of this R population. Molecular analyses revealed that an amino acid mutation (Asp-2078-Gly) was present in the R population by comparing ACCase gene sequences of the sensitive population (S). In addition, differences in susceptibility between the R and S population were unlikely to be related to herbicide metabolism. Furthermore, a new derived cleaved amplified polymorphic sequence (dCAPS) method was developed for detecting the Asp-2078-Gly mutation in P. fugax efficiently. We found that 93.75% of plants in the R population carried the Asp-2078-Gly mutation, and all the herbicide-resistant phenotype of this R population is inseparable from this mutation. This is the first report of cross resistance to ACCase inhibitors conferred by the Asp-2078-Gly target-site mutation in P. fugax. The research suggested the urgent need to improve the diversity of weed management practices to prevent the widespread evolution of herbicide resistance in P. fugax in China.

Most methods developed for detecting known single nucleotide polymorphisms (SNP) and deletion−insertion polymorphisms (DIP) are dependent on sequence conservation around the SNP/DIP and are therefore not suitable for application to heterogeneous organisms. Here we describe a novel, versatile and simple PCR-RFLP procedure baptised ‘derived Polymorphic Amplified Cleaved Sequence’ (dPACS) for genotyping individual samples. The notable advantage of the method is that it employs a pair of primers that cover the entire fragment to be amplified except for one or few diagnostic bases around the SNP/DIP being investigated. As such, it provides greater opportunities to introduce mismatches in one or both of the 35−55 bp primers for creating a restriction site that unambiguously differentiates wild from mutant sequences following PCR-RFLP and horizontal MetaPhorTM gel electrophoresis. Selection of effective restriction enzymes and primers is aided by the newly developed dPACS 1.0 software. The highly transferable dPACS procedure is exemplified here with the positive detection (in up to 24 grass and broadleaf species tested) of wild type proline106 of 5-enolpyruvylshikimate-3-phosphate synthase and its serine, threonine and alanine variants that confer resistance to glyphosate, and serine264 and isoleucine2041 which are key target-site determinants for weed sensitivities to some photosystem II and acetyl-CoA carboxylase inhibiting herbicides, respectively.

Asia minor bluegrass ( Polypogon fugax ) is a common and problematic weed throughout China. P. fugax that is often controlled by acetyl-CoA carboxylase (ACCase) inhibitors in canola fields. Herein, we confirmed a P. fugax population (R) showing resistance to all ACCase inhibitors tested with resistance indexes ranging from 5.4-18.4. We further investigated the resistance mechanisms of this R population. Molecular analyses revealed that an amino acid mutation (Asp-2078-Gly) was present in the R population by comparing ACCase gene sequences of the sensitive population (S). In addition, differences in susceptibility between the R and S population were unlikely to be related to herbicide metabolism. Furthermore, a new derived cleaved amplified polymorphic sequence (dCAPS) method was developed for detecting the Asp-2078-Gly mutation in P. fugax efficiently. We found that 93.75% of plants in the R population carried the Asp-2078-Gly mutation, and all the herbicide-resistant phenotype of this R population is inseparable from this mutation. This is the first report of cross resistance to ACCase inhibitors conferred by the Asp-2078-Gly target-site mutation in P. fug ax. The research suggested the urgent need to improve the diversity of weed management practices to prevent the widespread evolution of herbicide resistance in P. fug ax in China.

Most methods developed for detecting known single nucleotide polymorphisms (SNP) and deletion–insertion polymorphisms (DIP) are dependent on sequence conservation around the SNP/DIP and are therefore not suitable for application to heterogeneous organisms. Here we describe a novel, versatile and simple PCR-RFLP procedure baptised 'derived Polymorphic Amplified Cleaved Sequence' (dPACS) for genotyping individual samples. The notable advantage of the method is that it employs a pair of primers that cover the entire fragment to be amplified except for one or few diagnostic bases around the SNP/DIP being investigated. As such, it provides greater opportunities to introduce mismatches in one or both of the 35–55 bp primers for creating a restriction site that unambiguously differentiates wild from mutant sequences following PCR-RFLP and horizontal MetaPhorTM gel electrophoresis. Selection of effective restriction enzymes and primers is aided by the newly developed dPACS 1.0 software. The highly transferable dPACS procedure is exemplified here with the positive detection (in up to 24 grass and broadleaf species tested) of wild type proline106 of 5-enolpyruvylshikimate-3-phosphate synthase and its serine, threonine and alanine variants that confer resistance to glyphosate, and serine264 and isoleucine2041 which are key target-site determinants for weed sensitivities to some photosystem II and acetyl-CoA carboxylase inhibiting herbicides, respectively. [ABSTRACT FROM AUTHOR]