Transcriptional Regulation and Protein Localization of Zip10, Zip13 and Zip14 Transporters of Freshwater Teleost Yellow Catfish Pelteobagrus fulvidraco Following Zn Exposure in a Heterologous HEK293T Model

• Published in: International journal of molecular sciences 2022-07, Vol.23 (14), p.8034
• Main Authors: Liu, Sheng-Zan, Xu, Yi-Chuang, Tan, Xiao-Ying, Zhao, Tao, Zhang, Dian-Guang, Yang, Hong, Luo, Zhi
• Format: Article
• Language: English
• Subjects: Animals; Binding sites; Catfishes - genetics; Catfishes - metabolism; Cell membranes; Cytoplasm; Fluorescence; Fresh Water; Gene expression; Gene regulation; Golgi apparatus; HEK293 Cells; Homeostasis; Humans; KLF4 protein; Localization; Membrane Transport Proteins - metabolism; micronutrients; Nutrition research; Pelteobagrus fulvidraco; Promoters; Proteins; RNA, Messenger - metabolism; SLC39A transporter; Stat3 protein; subcellular localization; Transcription factors; transcriptional regulation; Vertebrates; Zinc - metabolism; zinc homeostasis
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms23148034

Zip family proteins are involved in the control of zinc (Zn) ion homeostasis. The present study cloned the promoters and investigated the transcription responses and protein subcellular localizations of three LIV-1 subfamily members ( , , and ) from common freshwater teleost yellow catfish, using in vitro cultured HEK293T model cells. The 2278 bp, 1917 bp, and 1989 bp sequences of , , and promoters, respectively, were subcloned into pGL3-Basic plasmid for promoter activity analysis. The pcDNA3.1 plasmid coding EGFP tagged pfZip10, pfZip13, and pfZip14 were generated for subsequent confocal microscope analysis. Several potential transcription factors' binding sites were predicted within the promoters. In vitro promoter analysis in the HEK293T cells showed that high Zn administration significantly reduced the transcriptional activities of the , , and promoters. The -2017 bp/-2004 bp MRE in the promoter, the -360 bp/-345 bp MRE in the promoter, and the -1457 bp/-1442 bp MRE in the promoter were functional loci that were involved in the regulation of the three . The -606 bp/-594 bp KLF4 binding site in the promoter was a functional locus responsible for zinc-responsive regulation of . The -1383 bp/-1375 bp STAT3 binding site in the promoter was a functional locus responsible for zinc-responsive regulation of . Moreover, confocal microscope analysis indicated that zinc incubation significantly reduced the fluorescence intensity of pfZip10-EGFP and pfZip14-EGFP but had no significant influence on pfZip13-EGFP fluorescence intensity. Further investigation found that pfZip10 localizes on cell membranes, pfZip14 colocalized with both cell membranes and lysosome, and pfZip13 colocalized with intracellular ER and Golgi. Our research illustrated the transcription regulation of , , and from under zinc administration, which provided a reference value for the mechanisms involved in Zip-family-mediated control of zinc homeostasis in vertebrates.