{"doi":"10.1042/bj2810829","title":"Two glucose transporter isoforms are sorted differentially and are expressed in distinct cellular compartments","abstract":"<jats:p>Rat GLUT4 (adipocyte/muscle-type glucose transporter) was expressed in two fibroblastic cell lines, Chinese hamster ovary (CHO) cells and 3T3-L1 fibroblasts, under the control of the methallothionein I promoter. Although immunoblotting with a GLUT4-specific anti-peptide antibody demonstrated that the amount of GLUT4 expressed was comparable with that in 3T3-L1 adipocytes and rat adipose tissues, no increase in 2-deoxy-D-glucose uptake was observed in the basal state in fibroblasts. Immunocytochemical studies showed that the expressed GLUT4 appeared to be localized in a specific region in the cytoplasm. These results were in marked contrast to those obtained in CHO cells expressing GLUT1 (HepG2/erythrocyte-type glucose transporter) using the same expression vector. In this case the expressed GLUT1 protein appeared to reside mainly on the plasma membranes, and a significant increase in glucose uptake was observed. Although insulin increased glucose uptake in CHO cells and 3T3-L1 fibroblasts as well as in the cells expressing rat GLUT4, an increment due to insulin above basal values was small, at most 2-fold, and no significant differences were observed in insulin-stimulated glucose uptake between transfected and parental cells. In addition, no apparent differences in the subcellular distribution of expressed GLUT4 were observed between the insulin-stimulated and the basal state. These results indicate that in fibroblastic cell lines GLUT1 and GLUT4 proteins are sorted in a different fashion, and the expression of GLUT4 protein per se is not enough to produce a large insulin-induced increase in glucose transport activity such as that observed in rat adipocytes and 3T3-L1 adipocytes. Thus unidentified aspects of the cellular environment which are present in the adipocytes but not in fibroblastic cell lines may be required for a large insulin-induced increase in glucose transport activity to be observed.</jats:p>","journal":"Biochemical Journal","year":1992,"id":650811,"datarank":0.5775221402565088,"base_score":3.8501476017100584,"endowment":3.8501476017100584,"self_citation_contribution":0.5775221402565088,"citation_network_contribution":0.0,"self_endowment_contribution":0.5775221402565088,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":46,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":40005,"name":"T Asano","orcid":null,"position":1,"is_corresponding":false},{"id":1697034,"name":"J L Lin","orcid":null,"position":2,"is_corresponding":false},{"id":1697039,"name":"K Tsukuda","orcid":null,"position":3,"is_corresponding":false},{"id":1697044,"name":"H Katagiri","orcid":null,"position":4,"is_corresponding":false},{"id":1697046,"name":"H Ishihara","orcid":null,"position":5,"is_corresponding":false},{"id":1697048,"name":"Y Yazaki","orcid":null,"position":6,"is_corresponding":false},{"id":163322,"name":"Y Oka","orcid":null,"position":7,"is_corresponding":false},{"id":1697031,"name":"Y Shibasaki","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Two glucose transporter isoforms are sorted differentially and are expressed in distinct cellular compartments","abstract":"<jats:p>Rat GLUT4 (adipocyte/muscle-type glucose transporter) was expressed in two fibroblastic cell lines, Chinese hamster ovary (CHO) cells and 3T3-L1 fibroblasts, under the control of the methallothionein I promoter. Although immunoblotting with a GLUT4-specific anti-peptide antibody demonstrated that the amount of GLUT4 expressed was comparable with that in 3T3-L1 adipocytes and rat adipose tissues, no increase in 2-deoxy-D-glucose uptake was observed in the basal state in fibroblasts. Immunocytochemical studies showed that the expressed GLUT4 appeared to be localized in a specific region in the cytoplasm. These results were in marked contrast to those obtained in CHO cells expressing GLUT1 (HepG2/erythrocyte-type glucose transporter) using the same expression vector. In this case the expressed GLUT1 protein appeared to reside mainly on the plasma membranes, and a significant increase in glucose uptake was observed. Although insulin increased glucose uptake in CHO cells and 3T3-L1 fibroblasts as well as in the cells expressing rat GLUT4, an increment due to insulin above basal values was small, at most 2-fold, and no significant differences were observed in insulin-stimulated glucose uptake between transfected and parental cells. In addition, no apparent differences in the subcellular distribution of expressed GLUT4 were observed between the insulin-stimulated and the basal state. These results indicate that in fibroblastic cell lines GLUT1 and GLUT4 proteins are sorted in a different fashion, and the expression of GLUT4 protein per se is not enough to produce a large insulin-induced increase in glucose transport activity such as that observed in rat adipocytes and 3T3-L1 adipocytes. Thus unidentified aspects of the cellular environment which are present in the adipocytes but not in fibroblastic cell lines may be required for a large insulin-induced increase in glucose transport activity to be observed.</jats:p>","is_dataset_classified":null,"base_score":3.8501476017100584,"endowment":3.8501476017100584,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"1536658","pmcid":"PMC1130764","openalex_id":"https://openalex.org/W69372474","authors":[],"funders":[],"total_grants":0,"fwci":3.4393,"citation_percentile":0.93234344,"influential_citations":0,"citation_trend":[{"year":2015,"count":2},{"year":2021,"count":1}],"oa_status":"closed","license":null,"oa_locations":[{"url":"https://portlandpress.com/biochemj/article-pdf/281/3/829/605700/bj2810829.pdf","host_type":"publisher"},{"url":"https://doi.org/10.1042/bj2810829","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/1536658","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/1130764","host_type":"repository"}],"fields_of_study":["Metabolism, Diabetes, and Cancer","Ion channel regulation and function","Muscle Physiology and Disorders","Adipose Tissue","Affinity Labels","Animals","Azides","Blotting, Western","CHO Cells","Cell Line","Cloning, Molecular","Cricetinae","DNA","Deoxyglucose","Disaccharides","Fibroblasts","Fluorescent Antibody Technique","Gene Expression","Glycosides","Metallothionein","Monosaccharide Transport Proteins","Promoter Regions, Genetic","Propylamines","Rats","Transfection"],"mesh_terms":["Adipose Tissue","Affinity Labels","Animals","Azides","Cell Line","Cloning, Molecular","Deoxyglucose","Disaccharides","DNA","Fibroblasts","Fluorescent Antibody Technique","Glycosides","Cricetinae","Metallothionein","Monosaccharide Transport Proteins","Promoter Regions, Genetic","Propylamines","Transfection","Blotting, Western","Gene Expression","CHO Cells","Rats"],"keywords":["GLUT4","Glucose transporter","GLUT1","Glucose uptake","Glucose Transporter Type 1","Chinese hamster ovary cell","Biology","Adipocyte","3T3-L1","Insulin","Internal medicine","Transfection","Endocrinology","Cell culture","Adipose tissue"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-10T06:09:45.565717Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}