Abstract

Edible fleshy fruits are important food sources in the human diet. Their yield and nutritional quality have long been considered as breeding targets for improvement. Various developing fleshy fruits with functional chloroplasts are capable of photosynthesis and contribute to fruit photosynthate, leading to the accumulation of metabolites associated with nutritional quality in ripe fruit. Although tomato high-pigment mutants with dark-green fruits have been isolated for more than 100 years, our understanding of the mechanism of chloroplast development in fleshy fruit remain poor. During the past few years, several transcription factors that regulate chloroplast development in fleshy fruit were identified through map-based cloning. In addition, substantial progress has been made in elucidating the mechanisms that how these transcription factors regulate chloroplast development. This review provides a summary and update on this progress, with a framework for further investigations of the multifaceted and hierarchical regulation of chloroplast development in fleshy fruit.

Highlights

  • Chloroplasts are essential organelles for converting light energy into chemical energy in plant and algal cells

  • We provide an updated summary of the progress made in transcriptional regulation of chloroplast development in fleshy fruits, and highlight major knowledge elucidating the transcriptional regulation of chloroplast development in fleshy fruits, and highlight gaps for future study

  • The CUL4-DAMAGED DNA BINDING PROTEIN1 (DDB1)-DET1 complex plays a vital role in regulating plant photomorphogenesis, suggesting that the light signal transduction pathway acts an important role in regulating chloroplast development in immature fleshy fruits

Read more

Summary

Introduction

Chloroplasts are essential organelles for converting light energy into chemical energy in plant and algal cells. MYB transcription factor (GLK2), which is a positive regulator of chloroplast development and pigment accumulation in tomato (Solanum lycopersicum) fruit [17,23]. Constitutive overexpression of AtGLK1 and AtGLK2 in tomato increased both the number and size of green fruit chloroplasts and promoted the accumulation and development of grana thylakoids, resulting in increased soluble solids and carotenoids in ripe fruit, for better nutritional quality, while no obvious alterations of leaf chlorophyll or chloroplasts were observed [17]. APRR2-Like Transcription Factors Regulate Chloroplast Development in Fleshy Fruits. It was reported that the APRR2 gene regulates pigment accumulation in melon and watermelon [29] Taken together, these studies indicate that the APRR2-Like gene has a conserved function in promoting fruit pigment accumulation and chloroplast development in flowering plants. The relationship between GLKs and APRR2-Like needs further investigation, it was suggested that APRR2-Like and GLK2 act independently as key transcription factors to directly activate genes involved in fruit chloroplast development [21]

TKN2 and TKN4 Regulate the Expression of GLK2 and APRR2
Other Transcription Factors Regulate Chloroplast Development in Fruit
LOL1 Controls Chloroplast Size in a Fruit-Specific Manner
ABA Signaling Regulates Chloroplast Development in Fleshy Fruits
Auxin Signaling Modulates GLK Expression
Improving Fruit Phytonutrients by Regulating Fruit Chloroplast Development
Findings
Conclusions and Perspectives
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call