The apple bHLH transcription factor MdbHLH3 functions in determining the fruit carbohydrates and malate.
Plant Biotechnol J
; 19(2): 285-299, 2021 02.
Article
em En
| MEDLINE
| ID: mdl-32757335
ABSTRACT
Changes in carbohydrates and organic acids largely determine the palatability of edible tissues of horticulture crops. Elucidating the potential molecular mechanisms involved in the change in carbohydrates and organic acids, and their temporal and spatial crosstalk are key steps in understanding fruit developmental processes. Here, we used apple (Malus domestica Borkh.) as research materials and found that MdbHLH3, a basic helix-loop-helix transcription factor (bHLH TF), modulates the accumulation of malate and carbohydrates. Biochemical analyses demonstrated that MdbHLH3 directly binds to the promoter of MdcyMDH that encodes an apple cytosolic NAD-dependent malate dehydrogenase, activating its transcriptional expression, thereby promoting malate accumulation in apple fruits. Additionally, MdbHLH3 overexpression increased the photosynthetic capacity and carbohydrate levels in apple leaves and also enhanced the carbohydrate accumulation in fruits by adjusting carbohydrate allocation from sources to sinks. Overall, our findings provide new insights into the mechanism of how the bHLH TF MdbHLH3 modulates the fruit quality. It directly regulates the expression of cytosolic malate dehydrogenase MdcyMDH to coordinate carbohydrate allocation and malate accumulation in apple.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Malus
Idioma:
En
Revista:
Plant Biotechnol J
Assunto da revista:
BIOTECNOLOGIA
/
BOTANICA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
China