The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform
Alan M Lloyd - One of the best experts on this subject based on the ideXlab platform.
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gain of function mutations in beet doda2 identify key residues for betalain pigment evolution
New Phytologist, 2018Co-Authors: Alexander Bean, Rasika M Sunnadeniya, Neda Akhavan, Annabelle Campbell, Matthew Brown, Alan M LloydAbstract:The key enzymatic step in betalain biosynthesis involves conversion of l-3,4-dihydroxyphenylalanine (L-DOPA) to betalamic acid. One class of enzymes capable of this is 3,4-dihydroxyphenylalanine 4,5-dioxygenase (DODA). In betalain-producing species, multiple paralogs of this gene are maintained. This study demonstrates which paralogs function in the betalain pathway and determines the residue changes required to evolve a betalain-nonfunctional DODA into a betalain-functional DODA. Functionalities of two pairs of DODAs were tested by expression in beets, Arabidopsis and yeast, and gene silencing was performed by virus-induced gene silencing. Site-directed mutagenesis identified amino acid residues essential for betalamic acid production. Beta vulgaris and Mirabilis jalapa both possess a DODA1 lineage that functions in the betalain pathway and at least one other lineage, DODA2, that does not. Site-directed mutagenesis resulted in betalain biosynthesis by a previously nonfunctional DODA, revealing key residues required for evolution of the betalain pathway. Divergent functionality of DODA paralogs, one clade involved in betalain biosynthesis but others not, is present in various Caryophyllales species. A minimum of seven amino acid residue changes conferred betalain enzymatic activity to a betalain-nonfunctional DODA paralog, providing insight into the evolution of the betalain pigment pathway in plants.
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Gain‐of‐function mutations in beet DODA2 identify key residues for betalain pigment evolution
New Phytologist, 2018Co-Authors: Alexander Bean, Matthew A Brown, Rasika M Sunnadeniya, Neda Akhavan, Annabelle Campbell, Alan M LloydAbstract:The key enzymatic step in betalain biosynthesis involves conversion of l-3,4-dihydroxyphenylalanine (L-DOPA) to betalamic acid. One class of enzymes capable of this is 3,4-dihydroxyphenylalanine 4,5-dioxygenase (DODA). In betalain-producing species, multiple paralogs of this gene are maintained. This study demonstrates which paralogs function in the betalain pathway and determines the residue changes required to evolve a betalain-nonfunctional DODA into a betalain-functional DODA. Functionalities of two pairs of DODAs were tested by expression in beets, Arabidopsis and yeast, and gene silencing was performed by virus-induced gene silencing. Site-directed mutagenesis identified amino acid residues essential for betalamic acid production. Beta vulgaris and Mirabilis jalapa both possess a DODA1 lineage that functions in the betalain pathway and at least one other lineage, DODA2, that does not. Site-directed mutagenesis resulted in betalain biosynthesis by a previously nonfunctional DODA, revealing key residues required for evolution of the betalain pathway. Divergent functionality of DODA paralogs, one clade involved in betalain biosynthesis but others not, is present in various Caryophyllales species. A minimum of seven amino acid residue changes conferred betalain enzymatic activity to a betalain-nonfunctional DODA paralog, providing insight into the evolution of the betalain pigment pathway in plants.
Yoshiharu Fujii - One of the best experts on this subject based on the ideXlab platform.
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l 3 3 4 dihydroxyphenyl alanine l dopa an allelochemical exuded from velvetbean mucuna pruriens roots
Plant Growth Regulation, 2005Co-Authors: Eiji Nishihara, Mohammad Masud Parvez, H Araya, Shigeto Kawashima, Yoshiharu FujiiAbstract:We investigated whether or not lettuce growth was inhibited by diffused L-3-(3,4-dihydroxyphenyl)alanine (L-DOPA), an allelochemical exuded from the roots of velvetbean (Mucuna pruriens (L.) DC. var. utilis) cultivars using a modified plant-box bioassay. For all the cultivars and one accession examined L-DOPA diffused from the roots and caused radicle and hypocotyl growth inhibition. A high correlation co-efficient (r = 0.838 to 0.982) was observed between L-DOPA concentration and lettuce seed sowing distance. L-DOPA diffused equally in all directions from roots at 0 mm position (close to root surface) in the plant-box, while the inhibition (%) of lettuce radicle growth gradually decreased with distance from the roots. For all cultivars the concentration of L-DOPA was significantly different at 0 mm position: being highest in cv. preta (167 μg/ml) and lowest in cv. jaspeada and cv. ana (13 μg/ml). The correlation between lettuce radicle growth inhibition and concentration of diffused L-DOPA was high (r = 0.856 to 0.966) in all cultivars and accession examined. However, the concentration of diffused L-DOPA did not correlate with the fresh weight concentration of L-DOPA measured in roots. The lettuce radicle growth inhibition from mucuna diffused L-DOPA was very similar that induced by synthetic L-DOPA, suggesting that diffused L-DOPA was the allelochemical responsible for growth inhibition.
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L-3-(3,4-Dihydroxyphenyl)alanine (L-DOPA), an allelochemical exuded from velvetbean (Mucuna pruriens) roots
Plant Growth Regulation, 2005Co-Authors: Eiji Nishihara, Mohammad Masud Parvez, H Araya, Shigeto Kawashima, Yoshiharu FujiiAbstract:We investigated whether or not lettuce growth was inhibited by diffused L -3-(3,4-dihydroxyphenyl)alanine ( L -DOPA), an allelochemical exuded from the roots of velvetbean ( Mucuna pruriens (L.) DC. var. utilis ) cultivars using a modified plant-box bioassay. For all the cultivars and one accession examined L -DOPA diffused from the roots and caused radicle and hypocotyl growth inhibition. A high correlation co-efficient ( r = 0.838 to 0.982) was observed between L -DOPA concentration and lettuce seed sowing distance. L -DOPA diffused equally in all directions from roots at 0 mm position (close to root surface) in the plant-box, while the inhibition (%) of lettuce radicle growth gradually decreased with distance from the roots. For all cultivars the concentration of L -DOPA was significantly different at 0 mm position: being highest in cv. preta (167 μg/ml) and lowest in cv. jaspeada and cv. ana (13 μg/ml). The correlation between lettuce radicle growth inhibition and concentration of diffused L -DOPA was high ( r = 0.856 to 0.966) in all cultivars and accession examined. However, the concentration of diffused L -DOPA did not correlate with the fresh weight concentration of L -DOPA measured in roots. The lettuce radicle growth inhibition from mucuna diffused L -DOPA was very similar that induced by synthetic L -DOPA, suggesting that diffused L -DOPA was the allelochemical responsible for growth inhibition.
Alexander Bean - One of the best experts on this subject based on the ideXlab platform.
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gain of function mutations in beet doda2 identify key residues for betalain pigment evolution
New Phytologist, 2018Co-Authors: Alexander Bean, Rasika M Sunnadeniya, Neda Akhavan, Annabelle Campbell, Matthew Brown, Alan M LloydAbstract:The key enzymatic step in betalain biosynthesis involves conversion of l-3,4-dihydroxyphenylalanine (L-DOPA) to betalamic acid. One class of enzymes capable of this is 3,4-dihydroxyphenylalanine 4,5-dioxygenase (DODA). In betalain-producing species, multiple paralogs of this gene are maintained. This study demonstrates which paralogs function in the betalain pathway and determines the residue changes required to evolve a betalain-nonfunctional DODA into a betalain-functional DODA. Functionalities of two pairs of DODAs were tested by expression in beets, Arabidopsis and yeast, and gene silencing was performed by virus-induced gene silencing. Site-directed mutagenesis identified amino acid residues essential for betalamic acid production. Beta vulgaris and Mirabilis jalapa both possess a DODA1 lineage that functions in the betalain pathway and at least one other lineage, DODA2, that does not. Site-directed mutagenesis resulted in betalain biosynthesis by a previously nonfunctional DODA, revealing key residues required for evolution of the betalain pathway. Divergent functionality of DODA paralogs, one clade involved in betalain biosynthesis but others not, is present in various Caryophyllales species. A minimum of seven amino acid residue changes conferred betalain enzymatic activity to a betalain-nonfunctional DODA paralog, providing insight into the evolution of the betalain pigment pathway in plants.
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Gain‐of‐function mutations in beet DODA2 identify key residues for betalain pigment evolution
New Phytologist, 2018Co-Authors: Alexander Bean, Matthew A Brown, Rasika M Sunnadeniya, Neda Akhavan, Annabelle Campbell, Alan M LloydAbstract:The key enzymatic step in betalain biosynthesis involves conversion of l-3,4-dihydroxyphenylalanine (L-DOPA) to betalamic acid. One class of enzymes capable of this is 3,4-dihydroxyphenylalanine 4,5-dioxygenase (DODA). In betalain-producing species, multiple paralogs of this gene are maintained. This study demonstrates which paralogs function in the betalain pathway and determines the residue changes required to evolve a betalain-nonfunctional DODA into a betalain-functional DODA. Functionalities of two pairs of DODAs were tested by expression in beets, Arabidopsis and yeast, and gene silencing was performed by virus-induced gene silencing. Site-directed mutagenesis identified amino acid residues essential for betalamic acid production. Beta vulgaris and Mirabilis jalapa both possess a DODA1 lineage that functions in the betalain pathway and at least one other lineage, DODA2, that does not. Site-directed mutagenesis resulted in betalain biosynthesis by a previously nonfunctional DODA, revealing key residues required for evolution of the betalain pathway. Divergent functionality of DODA paralogs, one clade involved in betalain biosynthesis but others not, is present in various Caryophyllales species. A minimum of seven amino acid residue changes conferred betalain enzymatic activity to a betalain-nonfunctional DODA paralog, providing insight into the evolution of the betalain pigment pathway in plants.
Eiji Nishihara - One of the best experts on this subject based on the ideXlab platform.
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l 3 3 4 dihydroxyphenyl alanine l dopa an allelochemical exuded from velvetbean mucuna pruriens roots
Plant Growth Regulation, 2005Co-Authors: Eiji Nishihara, Mohammad Masud Parvez, H Araya, Shigeto Kawashima, Yoshiharu FujiiAbstract:We investigated whether or not lettuce growth was inhibited by diffused L-3-(3,4-dihydroxyphenyl)alanine (L-DOPA), an allelochemical exuded from the roots of velvetbean (Mucuna pruriens (L.) DC. var. utilis) cultivars using a modified plant-box bioassay. For all the cultivars and one accession examined L-DOPA diffused from the roots and caused radicle and hypocotyl growth inhibition. A high correlation co-efficient (r = 0.838 to 0.982) was observed between L-DOPA concentration and lettuce seed sowing distance. L-DOPA diffused equally in all directions from roots at 0 mm position (close to root surface) in the plant-box, while the inhibition (%) of lettuce radicle growth gradually decreased with distance from the roots. For all cultivars the concentration of L-DOPA was significantly different at 0 mm position: being highest in cv. preta (167 μg/ml) and lowest in cv. jaspeada and cv. ana (13 μg/ml). The correlation between lettuce radicle growth inhibition and concentration of diffused L-DOPA was high (r = 0.856 to 0.966) in all cultivars and accession examined. However, the concentration of diffused L-DOPA did not correlate with the fresh weight concentration of L-DOPA measured in roots. The lettuce radicle growth inhibition from mucuna diffused L-DOPA was very similar that induced by synthetic L-DOPA, suggesting that diffused L-DOPA was the allelochemical responsible for growth inhibition.
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L-3-(3,4-Dihydroxyphenyl)alanine (L-DOPA), an allelochemical exuded from velvetbean (Mucuna pruriens) roots
Plant Growth Regulation, 2005Co-Authors: Eiji Nishihara, Mohammad Masud Parvez, H Araya, Shigeto Kawashima, Yoshiharu FujiiAbstract:We investigated whether or not lettuce growth was inhibited by diffused L -3-(3,4-dihydroxyphenyl)alanine ( L -DOPA), an allelochemical exuded from the roots of velvetbean ( Mucuna pruriens (L.) DC. var. utilis ) cultivars using a modified plant-box bioassay. For all the cultivars and one accession examined L -DOPA diffused from the roots and caused radicle and hypocotyl growth inhibition. A high correlation co-efficient ( r = 0.838 to 0.982) was observed between L -DOPA concentration and lettuce seed sowing distance. L -DOPA diffused equally in all directions from roots at 0 mm position (close to root surface) in the plant-box, while the inhibition (%) of lettuce radicle growth gradually decreased with distance from the roots. For all cultivars the concentration of L -DOPA was significantly different at 0 mm position: being highest in cv. preta (167 μg/ml) and lowest in cv. jaspeada and cv. ana (13 μg/ml). The correlation between lettuce radicle growth inhibition and concentration of diffused L -DOPA was high ( r = 0.856 to 0.966) in all cultivars and accession examined. However, the concentration of diffused L -DOPA did not correlate with the fresh weight concentration of L -DOPA measured in roots. The lettuce radicle growth inhibition from mucuna diffused L -DOPA was very similar that induced by synthetic L -DOPA, suggesting that diffused L -DOPA was the allelochemical responsible for growth inhibition.
Lijun Zhao - One of the best experts on this subject based on the ideXlab platform.
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Evolution of L-DOPA 4,5-dioxygenase activity allows for recurrent specialisation to betalain pigmentation in Caryophyllales
The New phytologist, 2019Co-Authors: Hester Sheehan, Alfonso Timoneda, Boas Pucker, Tao Feng, Nathanael Walker-hale, Samuel Lopez-nieves, Rui Guo, Won Cheol Yim, Roshani Badgami, Lijun ZhaoAbstract:The evolution of L-DOPA 4,5-dioxygenase activity, encoded by the gene DODA, was a key step in the origin of betalain biosynthesis in Caryophyllales. We previously proposed that L-DOPA 4,5-dioxygenase activity evolved via a single Caryophyllales-specific neofunctionalisation event within the DODA gene lineage. However, this neofunctionalisation event has not been confirmed and the DODA gene lineage exhibits numerous gene duplication events, whose evolutionary significance is unclear. To address this, we functionally characterised 23 distinct DODA proteins for L-DOPA 4,5-dioxygenase activity, from four betalain-pigmented and five anthocyanin-pigmented species, representing key evolutionary transitions across Caryophyllales. By mapping these functional data to an updated DODA phylogeny, we then explored the evolution of L-DOPA 4,5-dioxygenase activity. We find that low L-DOPA 4,5-dioxygenase activity is distributed across the DODA gene lineage. In this context, repeated gene duplication events within the DODA gene lineage give rise to polyphyletic occurrences of elevated L-DOPA 4,5-dioxygenase activity, accompanied by convergent shifts in key functional residues and distinct genomic patterns of micro-synteny. In the context of an updated organismal phylogeny and newly inferred pigment reconstructions, we argue that repeated convergent acquisition of elevated L-DOPA 4,5-dioxygenase activity is consistent with recurrent specialisation to betalain synthesis in Caryophyllales.
