title: The acyl-activating enzyme PhAAE13 is an alternative enzymatic source of precursors for anthocyanin biosynthesis in petunia flowers.
abstract: Anthocyanins, a class of flavonoids, are responsible for the orange to blue coloration of flowers and act as visual attractors to aid pollination and seed dispersal. Malonyl-CoA is the precursor for the formation of flavonoids and anthocyanins. Previous studies have suggested that malonyl-CoA is formed almost exclusively by acetyl-CoA carboxylase, which catalyzes the ATP-dependent formation of malonyl-CoA from acetyl-CoA and bicarbonate. In the present study, the full-length cDNA of Petunia hybrida acyl-activating enzyme 13 (PhAAE13), a member of clade VII of the AAE superfamily that encodes malonyl-CoA synthetase, was isolated. The expression of PhAAE13 was highest in corollas and was down-regulated by ethylene. Virus-induced gene silencing of petunia PhAAE13 significantly reduced anthocyanin accumulation, fatty acid content, and cuticular wax components content, and increased malonic acid content in flowers. The silencing of PhAAE3 and PhAAE14, the other two genes in clade VII of the AAE superfamily, did not change the anthocyanin content in petunia flowers. This study provides strong evidence indicating that PhAAE13, among clade VII of the AAE superfamily, is specifically involved in anthocyanin biosynthesis in petunia flowers.
authors.affiliation: College of Horticulture, South China Agricultural University, Guangzhou, China.|Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China.
authors.forename: Guoju
authors.initials: G
authors.lastname: Chen
authors.affiliation: College of Horticulture, South China Agricultural University, Guangzhou, China.
authors.forename: Heping
authors.initials: H
authors.lastname: Liu
authors.affiliation: Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wei
authors.affiliation: College of Horticulture, South China Agricultural University, Guangzhou, China.
authors.forename: Huina
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China.
authors.forename: Juanxu
authors.initials: J
authors.lastname: Liu
authors.affiliation: Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China.
authors.forename: Yixun
authors.initials: Y
authors.lastname: Yu
mesh_terms: D000595:Amino Acid Sequence; D000872:Anthocyanins / Q000378:metabolism*; D005030:Ethylenes / Q000378:metabolism; D035264:Flowers / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects / Q000528:radiation effects; D020868:Gene Silencing; D008314:Malonates / Q000378:metabolism*; D032306:Petunia / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment; D014466:Ultraviolet Rays
chemical_list: D000872:Anthocyanins; D005030:Ethylenes; D008314:Malonates; D010940:Plant Proteins; C036216:ethylene; C030290:malonic acid
keywords: AAE13; anthocyanin synthesis; malonic acid; malonyl-CoA; petunia