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目的:探究肝细胞核因子1α(HNF1α)通过葡萄糖转运蛋白(GLUT)调控肾脏葡萄糖重吸收的机制。方法:构建小鼠HNF1α表达载体，将重组质粒转染人胚肾HEK293T细胞和人肾小管上皮细胞HK2中过表达HNF1α，将HNF1α siRNA和GLUT2 siRNA转染入HEK293T细胞，采用流式细胞仪检测荧光葡萄糖类似物2-NBDG被细胞吸收的情况。采用Western印迹法检测HNF1α基因沉默后对GLUT2表达的影响。通过实时定量PCR检测HNF1α下游靶基因如GLUT2、钠-葡萄糖协同转运蛋白2(SGLT2)、胰岛素诱导基因1(INSIG1)等的mRNA水平，通过共聚焦免疫荧光检测GLUT2在肾上皮细胞的定位情况，使用荧光素酶报告基因和Western印迹法检测HNF1α对GLUT2的转录激活能力。通过凝胶迁移实验(EMSA)和染色质免疫共沉淀(ChIP)实验检测HNF1α与GLUT2的结合作用。结果:过表达HNF1α摄取2-NBDG的细胞比例明显高于对照组(n P<0.01)，HNF1α和GLUT2基因沉默后细胞对2-NBDG吸收作用减弱，HNF1α基因沉默后GLUT2表达减少。与对照组相比，过表达HNF1α使得肾脏包括GLUT2在内的有关糖转运基因表达水平上升(n P<0.01)。过表达HNF1α显著增加GLUT2转录活性，干涉HNF1α可下调GLUT2转录活性。此外，HNF1α可与GLUT2的启动子直接结合。n 结论:HNF1α通过直接结合GLUT2促进其表达，进而调节肾源细胞对葡萄糖重吸收作用。“,”Objective:This study aims to investigate the mechanism of hepatocyte nuclear factor 1α(HNF1α) regulating renal glucose resorption through glucose transporter(GLUT).Methods:HNF1α expression vectors of mice were constructed. The overexpressed HNF1α in HK2 was transfected by recombinant plasmids in human renal embryonic kidney HEK293T cells and human renal tubular epithelial cells. The HNF1α siRNA and GLUT2 siRNA were transfected into HEK293T cells. Flow cytometry was used to detect the absorption of fluorescent glucose analogue, 2-NBDG in cells. The GLUT2 expression was detected by Western blotting after HNF1α gene silencing. The mRNA levels of HNF1α downstream target genes such as GLUT2, sodium-dependent glucose transporter 2(SGLT2), and insulin induced gene 1(INSIG1) were detected by realtime quantitative PCR. The localization of GLUT2 in epithelial cells was measured by confocal immunofluorescence assay. The transcriptional activation ability of GLUT2 was detected by luciferase reporter gene and Western blotting. The binding effect of HNF1α and GLUT2 was detected by electrophoretic mobility shift assay(EMSA) and chromatin immunoprecipitation assay(ChIP) test.Results:The proportion of uptake of 2-NBDG by overexpressed HNF1α was significantly higher than that of the control group(n P<0.01). The absorption of 2-NBDG was weakened after HNF1α and GLUT2 gene silencing, while the GLUT2 expression was decreased after HNF1α gene silencing. The HNF1α overexpression increased the expression level of related sugar transporter genes including GLUT2 in the kidney compared with the control group(n P<0.01). HNF1α overexpression significantly increased the GLUT2 transcriptional activity and down-regulated the GLUT2 transcriptional activity via interfering HNF1α. Moreover, HNF1α directly bound to the promoter of GLUT2.n Conclusion:HNF1α promotes its expression by directly binding to GLUT2, and then regulates the resorption of glucose in nephrocytes.