Comparative Transcript Levels of Sugar Metabolism Genes Between the Canary Melon and a Vietnamese Non-Sweet Melon Cultivar

Phuong Dong Tran Nguyen, Nguyen Hoai Nguyen


Two different melon cultivars, Canary and Vietnamese non-sweet melons, are used to compare the fruit's sweetness levels. The results indicate that the Canary melon is much sweeter than the non-sweet melon. The transcript levels of the sugar metabolism genes, including Cucumis melo ACID INVERTASE 2 (CmAIN2) and SUCROSE SYNTHASE 1 (CmSUS1), are examined in two fruit tissues. PCR using cDNA and the electrophoresis assays indicate that the CmAIN2 and CmSUS1 primer sets are specific, and only one band of PCR product is obtained from all tested samples. The quantitative reverse transcription PCR (RT-qPCR) assay is applied to compare the transcript levels of the CmAIN2 and CmSUS1 genes in fruit tissues of the Canary and the Vietnamese non-sweet melons. Consistent with the sweetness levels, the CmAIN2 and CmSUS1 transcript levels are higher in the Canary melon than those in the non-sweet melon. These results imply that the local sugar metabolism in the fruits may also play an essential role in determining fruit sweetness. In addition, practically, the transcript levels of the CmAIN2 and CmSUS1 genes can be accessed and used to predict the sweetness of melon fruits early.


AIN2; Fruit sweetness; Non-sweet; SUS1; Sugar metabolism

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Amzeri, A., Badami, K., Zuhri, A., Pawana, G., Suhartono, S., Khoiri, S., Umam, A. S., Asmoro, Y., Rohmatin, S., Sa’diyah, H., & Badriyah, B. (2022). Assessment of genetic parameters for vitamin A, vitamin C, and TSS content results in melon line crosses at five maturity stages. International Journal of Agronomy, 2022, 3661952. DOI

Burger, Y., Paris, H. S., Cohen, R., Katzir, N., Tadmor, Y., Lewinsohn, E., & Schaffer, A. A. (2009). Genetic diversity of Cucumis melo. In J. Janick (Eds.), Horticultural Reviews (1st ed., pp. 165–198). Wiley. DOI

Chrost, B. & Schmitz, K. (1997). Changes in soluble sugar and activity of α-galactosidases and acid invertase during muskmelon (Cucumis melo L.) fruit development. Journal of Plant Physiology, 151(1), 41–50. DOI

Dahmani-Mardas, F., Troadec, C., Boualem, A., Lévêque, S., Alsadon, A. A., Aldoss, A. A., Dogimont, C., & Bendahmane, A. (2010). Engineering melon plants with improved fruit shelf life using the TILLING approach. PLoS One, 5, e15776. DOI

Dai, N., Cohen, S., Portnoy, V., Tzuri, G., Harel-Beja, R., Pompan-Lotan, M., Carmi, N., Zhang, G., Diber, A., Pollock, S., Karchi, H., Yeselson, Y., Petreikov, M., Shen, S., Sahar, U., Hovav, R., Lewinsohn, E., Tadmor, Y., Granot, D., … Schaffer, A. A. (2011). Metabolism of soluble sugars in developing melon fruit: A global transcriptional view of the metabolic transition to sucrose accumulation. Plant Molecular Biology, 76(1–2), 1–18. DOI

Durán-Soria, S., Pott, D. M., Osorio, S., & Vallarino, J. G. (2020). Sugar signaling during fruit ripening. Frontiers in Plant Science, 11, 564917. DOI

Gómez-García, R., Campos, D. A., Aguilar, C. N., Madureira, A. R., & Pintado, M. (2020). Valorization of melon fruit (Cucumis melo L.) by-products: phytochemical and biofunctional properties with emphasis on recent trends and advances. Trends in Food Science & Technology, 99, 507–519. DOI

Hackel, A., Schauer, N., Carrari, F., Fernie, A. R., Grimm, B., & Kühn, C. (2006). Sucrose transporter LeSUT1 and LeSUT2 inhibition affects tomato fruit development in different ways. The Plant Journal, 45(2), 180–192. DOI

Jia, H., Wang, Y., Sun, M., Li, B., Han, Y., Zhao, Y., Li, X., Ding, N., Li, C., Ji, W., & Jia, W. (2013). Sucrose functions as a signal involved in the regulation of strawberry fruit development and ripening. New Phytologist, 198(2), 453–465. DOI

Livak, K. J., & Schmittgen, T. D. (2001). Analysis of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2−ΔΔCT Method. Methods, 25(4), 402–408. DOI

Monforte, A. J., Diaz, A., Caño-Delgado, A., & van der Knaap, E. (2014). The genetic basis of fruit morphology in horticultural crops: lessons from tomato and melon. Journal of Experimental Botany, 65(16), 4625–4637. DOI

Nguyen, N. H. & Cheong, J. J. (2018). H2A.Z-containing nucleosomes are evicted to activate AtMYB44 transcription in response to salt stress. Biochemical and Biophysical Research Communications, 499(4), 1039–1043. DOI

Nguyen, P. D. T., Tran, D. T., Thieu, H. H., Lao, T. D., Le, T. A. H., Nguyen, N.H. (2023a) Hybridization between the Canary melon and a Vietnamese non-sweet melon cultivar aiming to improve the growth performance and fruit quality in melon (Cucumis melo L.). Molecular Biotechnology. DOI

Nguyen, T. D. P., Tran, T. D., Thieu, H. H., Le, H. A. T., Lao, D. T. (2023b). Establishment of protocol to investigate the expression of Sucrose Phosphate Synthase 2 (SPS2) in Vietnamese golden melon (Cucumis melo L.). HCMCOUJS-Engineering and Technology, 13(2), 55–59. DOI

Schemberger, M. O., Stroka, M. A., Reis, L., de Souza Los, K. K., de Araujo, G. A. T., Sfeir, M. Z. T., Galvão, C. W., Etto, R. M., Baptistão, A. R. G., & Ayub, R. A. (2020). Transcriptome profiling of non-climacteric 'yellow' melon during ripening: insights on sugar metabolism. BMC Genomics, 21(1), 262. DOI

Simms, D., Cizdziel, P. E., & Chomczynski, P. (1993). TRIzol: A new reagent for optimalsingle step isolation of RNA. Focus, 15, 532-535.

Sun, L., Wang, J., Lian, L., Song, J., Du, X., Liu, W., Zhao, W., Yang, L., Li, C., Qin, Y., & Yang, R. (2022). Systematic analysis of the sugar accumulation mechanism in sucrose- and hexose- accumulating cherry tomato fruits. BMC Plant Biology, 22(1), 303. DOI

Vennapusa, A. R., Somayanda, I. M., Doherty, C. J., & Jagadish, S. V. K. (2020). A universal method for high-quality RNA extraction from plant tissues rich in starch, proteins and fiber. Scientific Reports, 10, 16887. DOI


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