{"doi":"10.1016/j.cub.2007.05.048","title":"Cycling of CRYPTOCHROME Proteins Is Not Necessary for Circadian-Clock Function in Mammalian Fibroblasts","abstract":null,"journal":"Current Biology","year":2007,"id":610140,"datarank":0.6307038929086449,"base_score":4.204692619390966,"endowment":4.204692619390966,"self_citation_contribution":0.6307038929086449,"citation_network_contribution":0.0,"self_endowment_contribution":0.6307038929086449,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":66,"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":1568569,"name":"Akiko Hida","orcid":null,"position":1,"is_corresponding":false},{"id":321037,"name":"Daniel A. Anderson","orcid":"0000-0001-9655-323X","position":2,"is_corresponding":false},{"id":992859,"name":"Mariko Izumo","orcid":null,"position":3,"is_corresponding":false},{"id":329119,"name":"Carl Hirschie Johnson","orcid":"0000-0003-2878-3193","position":4,"is_corresponding":false},{"id":1568568,"name":"Yunzhen Fan","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Cycling of CRYPTOCHROME Proteins Is Not Necessary for Circadian-Clock Function in Mammalian Fibroblasts","abstract":"<h4>Background</h4>An interlocked transcriptional-translational feedback loop (TTFL) is thought to generate the mammalian circadian clockwork in both the central pacemaker residing in the hypothalamic suprachiasmatic nuclei and in peripheral tissues. The core circadian genes, including Period1 and Period2 (Per1 and Per2), Cryptochrome1 and Cryptochrome2 (Cry1 and Cry2), Bmal1, and Clock are indispensable components of this biological clockwork. The cycling of the PER and CRY clock proteins has been thought to be necessary to keep the mammalian clock ticking.<h4>Results</h4>We provide a novel cell-permeant protein approach for manipulating cryptochrome protein levels to evaluate the current transcription and translation feedback model of the circadian clockwork. Cell-permeant cryptochrome proteins appear to be functional on the basis of several criteria, including the abilities to (1) rescue circadian properties in Cry1(-/-)Cry2(-/-) mouse fibroblasts, (2) act as transcriptional repressors, and (3) phase shift the circadian oscillator in Rat-1 fibroblasts. By using cell-permeant cryptochrome proteins, we demonstrate that cycling of CRY1, CRY2, and BMAL1 is not necessary for circadian-clock function in fibroblasts.<h4>Conclusions</h4>These results are not supportive of the current version of the transcription and translation feedback-loop model of the mammalian clock mechanism, in which cycling of the essential clock proteins CRY1 and CRY2 is thought to be necessary.","is_dataset_classified":null,"base_score":4.204692619390966,"endowment":4.204692619390966,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"17583506","pmcid":"PMC3434691","openalex_id":"https://openalex.org/W2140241157","authors":[],"funders":[{"funder_name":"NIMH NIH HHS","grant_id":"R21 MH65910","title":null},{"funder_name":"NIMH NIH HHS","grant_id":"R01 MH043836","title":null},{"funder_name":"NIMH NIH HHS","grant_id":"R01 MH43836","title":null},{"funder_name":"NIMH NIH HHS","grant_id":"R21 MH065910","title":null},{"funder_name":"National Institutes of Health","grant_id":"5R01MH043836-13","title":"MOLECULAR/GENETIC ANALYSIS OF BIOLOGICAL CLOCKS IN CELLS"}],"total_grants":5,"fwci":3.2272,"citation_percentile":0.93340081,"influential_citations":0,"citation_trend":[{"year":2012,"count":6},{"year":2013,"count":4},{"year":2014,"count":1},{"year":2015,"count":1},{"year":2016,"count":4},{"year":2017,"count":3},{"year":2018,"count":1},{"year":2020,"count":1},{"year":2021,"count":2},{"year":2022,"count":3},{"year":2023,"count":1},{"year":2024,"count":1},{"year":2025,"count":2}],"oa_status":"bronze","license":"Elsevier Non-Commercial","oa_locations":[{"url":"http://www.cell.com/article/S0960982207014728/pdf","host_type":"journal"},{"url":"http://www.cell.com/article/S0960982207014728/pdf","host_type":"publisher"},{"url":"https://api.elsevier.com/content/article/PII:S0960982207014728?httpAccept=text/xml","host_type":"publisher"},{"url":"https://api.elsevier.com/content/article/PII:S0960982207014728?httpAccept=text/plain","host_type":"publisher"},{"url":"https://doi.org/10.1016/j.cub.2007.05.048","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/17583506","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/3434691","host_type":"repository"},{"url":"http://dx.doi.org/10.1016/j.cub.2007.05.048","host_type":""},{"url":"https://dx.doi.org/10.1016/j.cub.2007.05.048","host_type":""}],"fields_of_study":["Circadian rhythm and melatonin","Light effects on plants","Plant Molecular Biology Research","0301 basic medicine","0303 health sciences","03 medical and health sciences"],"mesh_terms":["Animals","Biological Clocks","Cell Line","Cell Membrane Permeability","Circadian Rhythm","Fibroblasts","Flavoproteins","Gene Expression Regulation","Humans","Transcription, Genetic","Trans-Activators","Mice, Knockout","Mice","Rats","Basic Helix-Loop-Helix Transcription Factors","Basic Helix-Loop-Helix Proteins","CLOCK Proteins","ARNTL Transcription Factors","Cryptochromes"],"keywords":["Cryptochrome","Clockwork","PER2","Circadian clock","Biology","PER1","Circadian rhythm","Cell biology","Bacterial circadian rhythms","Oscillating gene","Suprachiasmatic nucleus","Genetics","CLOCK","Neuroscience","Basic Helix-Loop-Helix Proteins","Mice, Knockout","Cell Membrane Permeability","Agricultural and Biological Sciences(all)","Flavoproteins","Transcription, Genetic","Biochemistry, Genetics and Molecular Biology(all)","ARNTL Transcription Factors","CLOCK Proteins","Fibroblasts","MOLNEURO","Cell Line","Rats","Cryptochromes","Mice","Gene Expression Regulation","Biological Clocks","Trans-Activators","Animals","Humans"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-07-31T19:52:14.577697Z","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":[]}