title: High-temperature inhibition of biosynthesis and transportation of anthocyanins results in the poor red coloration in red-fleshed Actinidia chinensis.
abstract: In plants, the role of anthocyanins trafficking in response to high temperature has been rarely studied, and therefore poorly understood. Red-fleshed kiwifruit has stimulated the world kiwifruit industry owing to its appealing color. However, fruit in warmer climates have been found to have poor flesh coloration, and the factors responsible for this response remain elusive. Partial correlation and regression analysis confirmed that accumulative temperatures above 25 °C (T25) was one of the dominant factors inhibiting anthocyanin accumulation in red-fleshed Actinidia chinensis, 'Hongyang'. Expression of structural genes, AcMRP and AcMYB1 in inner pericarp sampled from the two high altitudes (low temperature area), was notably higher than the low altitude (high temperature area) during fruit coloration. AcMYB1 and structural genes coordinate expression supported the MYB-bHLH (basic helix-loop-helix)-WD40 regulatory complex mediated downregulation of anthocyanin biosynthesis induced by high temperatures in kiwifruit. Moreover, cytological observations using the light and transmission electronic microscopy showed that there were a series of anthocyanic vacuolar inclusion (AVI)-like structures involved in their vacuolization process and dissolution of the pigmented bodies inside cells of fruit inner pericarp. Anthocyanin transport was inhibited by high temperature via retardation of vacuolization or reduction in AIV-like structure formation. Our findings strongly suggested that complex multimechanisms influenced the effects of high temperature on red-fleshed kiwifruit coloration.
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Speciality Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
authors.forename: Yu-Ping
authors.initials: YP
authors.lastname: Man
authors.forename: Yan-Chang
authors.initials: YC
authors.lastname: Wang
authors.forename: Zuo-Zhou
authors.initials: ZZ
authors.lastname: Li
authors.forename: Zheng-Wang
authors.initials: ZW
authors.lastname: Jiang
authors.forename: Hong-Li
authors.initials: HL
authors.lastname: Yang
authors.forename: Jun-Jie
authors.initials: JJ
authors.lastname: Gong
authors.forename: Shi-Song
authors.initials: SS
authors.lastname: He
authors.forename: Shi-Quan
authors.initials: SQ
authors.lastname: Wu
authors.forename: Zuo-Quan
authors.initials: ZQ
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Zheng
authors.forename: Zhong-Yan
authors.initials: ZY
authors.lastname: Wang
mesh_terms: D029042:Actinidia / Q000166:cytology / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D000872:Anthocyanins / Q000378:metabolism*; D001483:Base Sequence; D001692:Biological Transport; D005638:Fruit / Q000166:cytology / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant; D008027:Light; D008969:Molecular Sequence Data; D010802:Phylogeny; D010858:Pigmentation; D017422:Sequence Analysis, DNA; D013696:Temperature
chemical_list: D000872:Anthocyanins