{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T21:53:32Z","timestamp":1770501212586,"version":"3.49.0"},"reference-count":10,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2005,2,4]],"date-time":"2005-02-04T00:00:00Z","timestamp":1107475200000},"content-version":"vor","delay-in-days":10506,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal Cellular Physiology"],"published-print":{"date-parts":[[1976,5]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Cytosol thymidine kinase (TK) and deoxycytidylate (dCMP) deaminase formation was investigated in synchronized cultures of K12 Chinese hamster cells which have a temperature\u2010sensitive lesion affecting the initiation of DNA synthesis. Enzyme formation was found to be cycloheximide\u2010sensitive and also temperature\u2010dependent. Beginning at about six hours after addition of medium with 10% calf serum to serum\u2010depleted K12 cultures, cytosol TK and dCMP deaminase activities increased when the cultures were incubated at 36.5\u00b0, but not at 40.5\u00b0. When cultures were shifted from 36.5\u00b0 to 40.5\u00b0 at 4, 6, or 8 hours after serum addition, TK activity continued to increase, though not to the level observed at ten hours in cultures maintained at 36.5\u00b0. Actinomycin D addition at the time of serum reversal or four hours later blocked the TK increase normally observed at the permissive temperature at ten hours. However, when actinomycin D addition was delayed for six or eight hours after serum addition, the increase in TK measured at ten hours resembled that observed in the temperature shift\u2010up experiments. The results provide evidence that the mutation in K12 Chinese hamster cells most likely blocks the progression through G1 into S and suggest that transcription or post\u2010transcriptional processing required for TK formation is affected.<\/jats:p>","DOI":"10.1002\/jcp.1040880108","type":"journal-article","created":{"date-parts":[[2005,2,26]],"date-time":"2005-02-26T02:54:32Z","timestamp":1109386472000},"page":"57-64","source":"Crossref","is-referenced-by-count":23,"title":["Formation of thymidine kinase and deoxycytidylate deaminase in synchronized cultures of chinese hamster cells temperature\u2010sensitive for DNA synthesis"],"prefix":"10.1002","volume":"88","author":[{"given":"Saul","family":"Kit","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"George N.","family":"Jorgensen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2005,2,4]]},"reference":[{"key":"e_1_2_1_2_1","doi-asserted-by":"crossref","unstructured":"Dubbs D. R. andS.Kit1976Reactivation of chick erythrocyte nuclei in heterokaryons with temperature\u2010sensitive Chinese hamster cells.Somatic Cell Genetics in press.","DOI":"10.1007\/BF01539238"},{"key":"e_1_2_1_3_1","unstructured":"Kit S.1975Thymidine kinase DNA synthesis and cancer.Mol. and Cellular Biochemistry in press."},{"key":"e_1_2_1_4_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00486015"},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.1083\/jcb.61.1.35"},{"key":"e_1_2_1_6_1","first-page":"103","volume-title":"Control Processes in Neoplasia","author":"Kit S.","year":"1974"},{"key":"e_1_2_1_7_1","first-page":"1859","article-title":"Arabinofuranosylcytosine\u2010induced stimulation of thymidine kinase and deoxycytidylic deaminase activities in mammalian cultures","volume":"26","author":"Kit S.","year":"1966","journal-title":"Cancer Res."},{"key":"e_1_2_1_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/jcp.1040820302"},{"key":"e_1_2_1_9_1","doi-asserted-by":"publisher","DOI":"10.1002\/jcp.1040820303"},{"key":"e_1_2_1_10_1","doi-asserted-by":"publisher","DOI":"10.1002\/jcp.1040820304"},{"key":"e_1_2_1_11_1","doi-asserted-by":"publisher","DOI":"10.1002\/jcp.1040840114"}],"container-title":["Journal of Cellular Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fjcp.1040880108","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jcp.1040880108","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,11,12]],"date-time":"2023-11-12T06:08:49Z","timestamp":1699769329000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/jcp.1040880108"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1976,5]]},"references-count":10,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1976,5]]}},"alternative-id":["10.1002\/jcp.1040880108"],"URL":"https:\/\/doi.org\/10.1002\/jcp.1040880108","archive":["Portico"],"relation":{},"ISSN":["0021-9541","1097-4652"],"issn-type":[{"value":"0021-9541","type":"print"},{"value":"1097-4652","type":"electronic"}],"subject":[],"published":{"date-parts":[[1976,5]]}}}