{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T12:21:54Z","timestamp":1789129314962,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T00:00:00Z","timestamp":1789084800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Gansu Academy of Agricultural Sciences","award":["2025 GAAS14"],"award-info":[{"award-number":["2025 GAAS14"]}]},{"award":["2025 GAAS14"],"award-info":[{"award-number":["2025 GAAS14"]}],"id":[{"id":"https:\/\/ror.org\/001tdwk28","id-type":"ROR","asserted-by":"publisher"}]},{"name":"National Bulk Vegetable Industry Technology System","award":["CARS-23-G19"],"award-info":[{"award-number":["CARS-23-G19"]}]},{"name":"Gansu Provincial Science and Technology Mission Project","award":["24CXNA059"],"award-info":[{"award-number":["24CXNA059"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Plant hexokinase (HXK) is a key enzyme in carbohydrate metabolism that serves a dual function by catalyzing hexose phosphorylation and participating in sugar signaling. In this study, expression pattern analysis and reverse-genetic approaches were used to investigate the role of CsHXK2 in cucumber floral development. CsHXK2 was predominantly expressed in the stamens and nectary of male flowers and in the stigma, nectary, and ovary of female flowers. The CsHXK2 protein was localized to chloroplasts. Silencing CsHXK2 significantly increased glucose, fructose, and sucrose levels in the examined tissues of both male and female flowers. This increase was accompanied by reduced activities of HXK, PFK, AI, SS-I, and NI and enhanced activities of SPS and SS-II, with these changes being more pronounced in female flowers than in male flowers. Gene expression analysis further revealed that CsHXK2 silencing induced tissue-specific changes in the expression of sugar-metabolism-related genes in both male and female flowers. These results demonstrate that CsHXK2 contributes to the maintenance of sugar homeostasis in cucumber floral organs. Moreover, male and female floral organs exhibit distinct responses to HXK-mediated regulation of sugar metabolism, suggesting that CsHXK2 may influence cucumber flower development by modulating carbon allocation and sugar signaling.<\/jats:p>","DOI":"10.3390\/plants15182791","type":"journal-article","created":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T10:51:37Z","timestamp":1789123897000},"page":"2791","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Responses of Male and Female Cucumber Flowers to CsHXK2-Mediated Sugar Metabolism"],"prefix":"10.3390","volume":"15","author":[{"given":"Dongqin","family":"Zhang","sequence":"first","affiliation":[{"name":"Vegetable Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Dong","family":"Hou","sequence":"additional","affiliation":[{"name":"Vegetable Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Panpan","family":"Duan","sequence":"additional","affiliation":[{"name":"Vegetable Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Huiting","family":"Wang","sequence":"additional","affiliation":[{"name":"Vegetable Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Hongzhong","family":"Yue","sequence":"additional","affiliation":[{"name":"Vegetable Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Yali","family":"Li","sequence":"additional","affiliation":[{"name":"Vegetable Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"494","DOI":"10.1007\/s00344-018-9864-1","article-title":"Phloem unloading strategies and mechanisms in crop fruits","volume":"38","author":"Si","year":"2019","journal-title":"J. Plant Growth Regul."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Li, J., Yao, X., Zhang, J., Li, M., Xie, Q., Yang, Y., Chen, G., Zhang, X., and Hu, Z. (2025). Genome-wide identification and expression analysis of hexokinase gene family under abiotic stress in tomato. Plants, 14.","DOI":"10.3390\/plants14030441"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"109603","DOI":"10.1016\/j.plaphy.2025.109603","article-title":"Hexokinase gene CsHXK4 positively regulates cold resistance in tea plants (Camellia sinensis)","volume":"221","author":"Wang","year":"2025","journal-title":"Plant Physiol. Biochem."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1007\/s10930-017-9718-x","article-title":"Conformational characteristics of rice hexokinase OsHXK7 as a moonlighting protein involved in sugar signalling and metabolism","volume":"36","author":"Wang","year":"2017","journal-title":"Protein J."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Impe, D., Reitz, J., K\u00f6pnick, C., Rolletschek, H., B\u00f6rner, A., Senula, A., and Nagel, M. (2022). Assessment of pollen viability for wheat. Front. Plant Sci., 10.","DOI":"10.3389\/fpls.2019.01588"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"765","DOI":"10.1038\/s42003-021-02283-y","article-title":"Guard cells control hypocotyl elongation through HXK1, HY5, and PIF4","volume":"4","author":"Kelly","year":"2021","journal-title":"Commun. Biol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1151","DOI":"10.1093\/pcp\/pcx062","article-title":"Plant hexokinases are multifaceted proteins","volume":"58","year":"2017","journal-title":"Plant Cell Physiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"411","DOI":"10.1007\/s00425-008-0746-9","article-title":"Expression and evolutionary features of the hexokinase gene family in Arabidopsis","volume":"228","author":"Karve","year":"2008","journal-title":"Planta"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"598","DOI":"10.1007\/s00425-006-0251-y","article-title":"Structure, expression and functional analysis of the hexokinase gene family in rice (Oryza sativa L.)","volume":"224","author":"Cho","year":"2006","journal-title":"Planta"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Jiao, F., Chen, Y., Zhang, D., and Wu, J. (2023). Genome-wide characterization of soybean hexokinase genes reveals a positive role of GmHXK15 in alkali stress response. Plants, 12.","DOI":"10.3390\/plants12173121"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1104\/pp.108.131227","article-title":"Role of the rice hexokinases OsHXK5 and OsHXK6 as glucose sensors","volume":"149","author":"Cho","year":"2009","journal-title":"Plant Physiol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1007\/s10535-011-0025-7","article-title":"Subcellular localization of rice hexokinase (OsHXK) family members in the mesophyll protoplasts of tobacco","volume":"55","author":"Cheng","year":"2011","journal-title":"Biol. Plant."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Nilsson, A., Olsson, T., Ulfstedt, M., Thelander, M., and Ronne, H. (2011). Two novel types of hexokinases in the moss. Physcomitrella patens. BMC Plant Biol., 11.","DOI":"10.1186\/1471-2229-11-32"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Hu, D.G., Sun, C.H., Zhang, Q.Y., An, J.P., You, C.X., and Hao, Y.J. (2016). Glucose sensor MdHXK1 phosphorylates and stabilizes MdbHLH3 to promote anthocyanin biosynthesis in apple. PLoS Genet., 12.","DOI":"10.1371\/journal.pgen.1006273"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"712","DOI":"10.1271\/bbb.56.712","article-title":"Malfunction of enzyme systems involved in the regeneration of glutathione in perennials at low temperatures","volume":"56","author":"Kuroda","year":"1992","journal-title":"Biosci. Biotechnol. Biochem."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Zhang, X., Wang, S., Ren, Y., Gan, C., Li, B., Fan, Y., Zhao, X., and Yuan, Z. (2022). Identification, analysis and gene cloning of the SWEET gene family provide insights into sugar transport in pomegranate (Punica granatum). Int. J. Mol. Sci., 23.","DOI":"10.3390\/ijms23052471"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Lugassi, N., Yadav, B.S., Egbaria, A., Wolf, D., Kelly, G., Neuhaus, E., Raveh, E., Carmi, N., and Granot, D. (2019). Expression of Arabidopsis Hexokinase in tobacco guard cells increases water-use efficiency and conferstolerance to drought and salt stress. Plants, 8.","DOI":"10.3390\/plants8120613"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1088","DOI":"10.1111\/nph.17427","article-title":"HEXOKINASE1 signalling promotes shoot branching and interacts with cytokinin and strigolactone pathways","volume":"231","author":"Barbier","year":"2021","journal-title":"New Phytol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"115078","DOI":"10.1016\/j.foodres.2024.115078","article-title":"A comparative metabolomics study of delayed-harvested and pumpkin grafted cucumbers","volume":"196","author":"Yang","year":"2024","journal-title":"Food Res. Int."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1016\/j.tplants.2019.02.009","article-title":"Evolution of guard-cell theories: The story of sugars","volume":"24","author":"Granot","year":"2019","journal-title":"Trends Plant Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"438","DOI":"10.1111\/tpj.14472","article-title":"Resolving subcellular plant metabolism","volume":"100","author":"Weckwerth","year":"2019","journal-title":"Plant J."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1007\/s00425-018-2888-8","article-title":"Genome-wide identification of hexokinase gene family in Brassica napus: Structure, phylogenetic analysis, expression, and functional characterization","volume":"248","author":"Wang","year":"2018","journal-title":"Planta"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"143932","DOI":"10.1016\/j.gene.2019.06.022","article-title":"Identification of hexokinase family members in pear (Pyrus \u00d7 bretschneideri) and functional exploration of PbHXK1 in modulating sugar content and plant growth","volume":"711","author":"Zhao","year":"2019","journal-title":"Gene"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Tong, P., Liao, G., Lu, D., Zhou, X., Zhang, W., Xu, Q., Wu, C., and Wang, J. (2024). ZjHXK5 and ZjHXK6 negatively regulate the sugar metabolism of Ziziphus jujuba Mill. Front. Plant Sci., 15.","DOI":"10.3389\/fpls.2024.1335120"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1016\/j.ecoenv.2019.05.037","article-title":"Selenium impedes cadmium and arsenic toxicity in potato by modulating carbohydrate and nitrogen metabolism","volume":"180","author":"Shahid","year":"2019","journal-title":"Ecotoxicol. Environ. Saf."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Aguilera-Alvarado, G.P., Gonzalez-Gutierrez, A., Estrada-Antolin, S.A., and Sanchez-Nieto, S. (2019). Biochemical properties and subcellular localization of six members of the HXK family in maize and its metabolic contribution to embryo germination. BMC Plant Biol., 19.","DOI":"10.1186\/s12870-018-1605-x"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2977","DOI":"10.1104\/pp.17.01472","article-title":"The Glucose Sensor MdHXK1 Phosphorylates a Tonoplast Na+\/H+ Exchanger to Improve Salt Tolerance","volume":"176","author":"Sun","year":"2018","journal-title":"Plant Physiol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1093\/plcell\/koac317","article-title":"Cucumber STACHYOSE SYNTHASE is regulated by its cis-antisense RNA as CsSTS to balance source\u2013sink carbon partitioning","volume":"35","author":"Dai","year":"2023","journal-title":"Plant Cell"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"6995","DOI":"10.1038\/s41467-021-27259-8","article-title":"VviPLATZ1 is a major factor that controls female flower morphology determination in grapevine","volume":"12","author":"Torregrosa","year":"2021","journal-title":"Nat. Commun."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"411","DOI":"10.1007\/s00497-018-0346-1","article-title":"The sex-determining gene CitACS4 is a pleiotropic regulator of flower and fruit development in watermelon (Citrullus lanatus)","volume":"31","author":"Aguado","year":"2018","journal-title":"Plant Reprod."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Hu, L., Tian, J., Zhang, F., Song, S., Cheng, B., Liu, G., Liu, H., Zhao, X., Wang, Y., and He, H. (2024). Functional Characterization of CsSWEET5a, a Cucumber Hexose Transporter That Mediates the Hexose Supply for Pollen Development and Rescues Male Fertility in Arabidopsis. Int. J. Mol. Sci., 25.","DOI":"10.3390\/ijms25021332"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1056","DOI":"10.1021\/acs.jafc.2c06783","article-title":"New fructokinase, OsFRK3, regulates starch accumulation and grain filling in rice","volume":"71","author":"Zhang","year":"2023","journal-title":"J. Agric. Food Chem."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"112321","DOI":"10.1016\/j.plantsci.2024.112321","article-title":"SlTDF1: A key regulator of tapetum degradation and pollen development in tomato","volume":"351","author":"Sun","year":"2025","journal-title":"Plant Sci."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Cheng, L., Jia, J., He, X., Luo, Z., Wang, Z., Yang, J., and Xu, X. (2023). Genome-wide identification and analysis of the invertase gene family in tobacco (Nicotiana tabacum) reveals NtNINV10 participating the sugar metabolism. Front. Plant Sci., 14.","DOI":"10.3389\/fpls.2023.1164296"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"111500","DOI":"10.1016\/j.plaphy.2026.111500","article-title":"Metabolomics and transcriptomics analyses reveal the synthetic pathway of sweet substances in the bamboo shoots of dendrocalamus brandisii","volume":"237","author":"Ma","year":"2026","journal-title":"Plant Physiol. Biochem."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Wang, Z., Li, W., Li, G., Yang, H., Guo, J., and Lu, D. (2026). Salicylic acid modulates source-flow-sink coordination to stabilize carbon allocation and grain yield in waxy maize under heat stress. J. Integr. Agric., online.","DOI":"10.1016\/j.jia.2026.04.011"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Zhai, X., Cai, C., He, C., Mao, Z., Liu, Z., Zhang, J., Liu, J.H., and Li, C. (2026). ABA orchestrates the expression of SWEET16 for sugar accumulation via phosphorylation and transcriptional mechanisms in citrus. J. Integr. Plant Biol., 1\u201321.","DOI":"10.1111\/jipb.70340"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Geng, M.T., Yang, Y.Y., Wang, Y.L., Wu, X.H., Sun, C., Li, R.M., Fu, S.P., Duan, R.J., Liu, J., and Hu, X.W. (2017). Structure, Expression, and Functional Analysis of the Hexokinase Gene Family in Cassava. Int. J. Mol. Sci., 18.","DOI":"10.3390\/ijms18051041"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Dong, M., Shan, L., Wang, W., Wang, Y., Shan, L., Liu, X., and Ren, H. (2025). B3 Superfamily in cucumber (Cucumis sativus L.): Identification, evolution, expression patterns, and function in glandular trichome development. Int. J. Mol. Sci., 26.","DOI":"10.3390\/ijms26094031"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"800","DOI":"10.1002\/bmb.21552","article-title":"Real-time quantitative PCR: A tool for absolute and relative quantification","volume":"49","author":"Harshitha","year":"2021","journal-title":"Biochem. Mol. Biol. Educ."}],"container-title":["Plants"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2223-7747\/15\/18\/2791\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T11:17:00Z","timestamp":1789125420000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2223-7747\/15\/18\/2791"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,11]]},"references-count":40,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["plants15182791"],"URL":"https:\/\/doi.org\/10.3390\/plants15182791","relation":{},"ISSN":["2223-7747"],"issn-type":[{"value":"2223-7747","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,11]]}}}