Functional Identification of Apple MdGLK1 Which Regulates Chlorophyll Biosynthesis in Arabidopsis
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Apple is one of the most prominent fleshy fruits in the world, and photosynthesis is the main factor that influences the intrinsic quality of the fruit. Chlorophyll is an important pigment in photosynthesis and is highly abundant in apple leaves. Although there are many studies on chlorophyll metabolism in apples, most studies have focused on cultivation management, and related molecular regulation research is weak. In this study, we characterized a GOLDEN2-like transcription factor, MdGLK1, in detail. MdGLK1 was expressed mainly in leaves according to gene expression assay and GUS-staining analysis. The MdGLK1 protein was located in the nucleus and exhibited strong transactivation activity. A yeast two-hybrid assay revealed that MdGLK1 formed a homodimer, and the GCT box domain was responsible for dimerization. Overexpression of MdGLK1 restored the chloroplast-defective phenotype of the glk1glk2 mutant and promoted the transcript levels of chlorophyll biosynthesis and photosynthesis-related genes. Together, these results suggest that MdGLK1 positively regulates chlorophyll biosynthesis and may be a candidate gene for improved intrinsic qualities of apple fruit.
KeywordsApple Chlorophyll GLK Transgenic Arabidopsis
This work was supported by National Natural Science Foundation of China (No. 31672116), National key research and development plan and the Program of Developing the Modern Agricultural Industry Technology System (Apple) (CARS-28). The authors would like to thank Dr. Dong Liu of Jiangxi Agricultural University for the glk1glk2 mutant and thank Comprehensive Laboratory of Pomology Biology, Institute of Pomology, CAAS, for providing equipment and technical support. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted.
XHA conducted experiments and wrote the manuscript. YT and YHC conceived and designed research. EML and ML analysed data. CGC revised the manuscript. All authors read and approved the manuscript.
- Cheng L, Lai K (2013) Golden2-like (GLK2) transcription factor: developmental control of tomato fruit photosynthesis and its contribution to ripe fruit characteristics[M]. University of California, Davis, 2013Google Scholar
- Jhadeswar M, Michael W, Ghislaine A, Radhey P, Darrell D, Jas S, Rajagopal S (2014) Arabidopsis GOLDEN2-LIKE (GLK) transcription factors activate jasmonic acid (JA)-dependent disease susceptibility to the biotrophic pathogen Hyaloperonospora arabidopsidis, as well as JA-independent plant immunity against the necrotrophic pathogen Botrytis cinerea. Mol Plant Pathol 15:174–184CrossRefGoogle Scholar
- Kobayashi K, Sasaki D, Noguchi K, Fujinuma D, Komatsu H, Kobayahsi M, Sato M, Toyooka K, Sugimoto K, Niyogi KK, Wada H, Masuda T (2013) Photosynthesis of root chloroplasts developed in Arabidopsis lines overexpressing GOLDEN2-LIKE transcription factors. Plant Cell Physiol 54:1365–1377CrossRefGoogle Scholar
- Langdale JA, Kidner CA (1994) bundle sheath defective, a mutation that disrupts cellular differentiation in maize leaves. Development 120:673–681Google Scholar
- Powell ALT, Nguyen CV, Hill T, Cheng KL, Aktas RFH, Ashrafi H, Pons C, Fernández-Muňoz R, Vicente A, Lopez-Baltazar J, Barry CS, Liu Y, Chetelat R, Granell A, Deynze AV, Giovannoni JJ, Bennett AB (2012) Uniform ripening encodes a Golden 2-like transcription factor regulating tomato fruit chloroplast development. Science 336:1711–1715CrossRefGoogle Scholar
- Riechmann JL, Heard J, Martin G, Reuber L, Jiang CZ, Keddie J, Adam L, Pineda O, Ratcliffe OJ, Samaha RR, Creelman R, Pilgrim M, Broun P, Zhang JZ, Ghandehari D, Sherman BK, Yu GL (2000) Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes. Science 290:2105–2110CrossRefGoogle Scholar
- Tang X, Miao M, Niu X, Zhang D, Cao X, Jin X, Zhu Y, Fan Y, Wang H, Liu Y, Sui Y, Wang W, Wang A, Xiao F, Giovannoni J, Liu Y (2016) Ubiquitin-conjugated degradation of golden 2-like transcription factor is mediated by CUL4-DDB1-based E3 ligase complex in tomato. New Phytol 209:1028–1039CrossRefGoogle Scholar
- Zhao SJ (2004) Plant physiology experiment report. Chinese Agriculture Science & Technology Press, Beijing, pp 41–45Google Scholar