{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,2]],"date-time":"2025-11-02T16:05:04Z","timestamp":1762099504645},"reference-count":43,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2001,5,15]],"date-time":"2001-05-15T00:00:00Z","timestamp":989884800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J of Cellular Biochemistry"],"published-print":{"date-parts":[[2001,9]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>CCAAT\/Enhancer binding proteins (C\/EBPs) play important roles in the regulation of cell growth and differentiation. This study investigated the expression and function of C\/EBP\u03b2 isoforms in the mouse mammary gland, mammary tumors, and a nontransformed mouse mammary epithelial cell line (HC11). C\/EBP\u03b2 mRNA levels are 2\u20135\u2010fold higher in mouse mammary tumors derived from MMTV\/c\u2010neu transgenic mice compared with lactating and involuting mouse mammary gland. The \u201cfull\u2010length\u201d 38 kd C\/EBP\u03b2 LAP (\u201cLiver\u2010enriched Activator Protein\u201d) isoform is the predominant C\/EBP\u03b2 protein isoform in mammary tumor whole cell lysates, however, the truncated 20 kd C\/EBP\u03b2 LIP (\u201cLiver\u2010enriched Inhibitory Protein\u201d) isoform is also present at detectable levels (mean LAP:LIP ratio 5.3:1). The mammary tumor C\/EBP\u03b2 LAP:LIP ratio decreases 70% (from 5.3:1 to 1.6:1) when lysate preparation is switched from a rapid whole cell lysis protocol to a multistep nuclear\/cytoplasmic fractionation protocol. In contrast to mammary tumors, only the C\/EBP\u03b2 LAP isoform is detectable in the mammary gland whole cell and nuclear lysates; the truncated \u201cLIP\u201d isoform is undetectable regardless of isolation protocol. Ectopic over expression of C\/EBP\u03b2 LIP or C\/EBP\u03b2 LAP did not alter HC11 growth rates. However, C\/EBP\u03b2 LIP over expressing HC11 cells (LAP:LIP ratio of \u223c1:1) exhibited a consistent 2\u20134 h delay in G<jats:sub>0<\/jats:sub>\/S phase transition. C\/EBP\u03b2 LIP overexpressing HC11 cells did not express \u03b2\u2010casein mRNA (mammary epithelial cell differentiation marker) in response to lactogenic hormones. This defect in \u03b2\u2010casein expression was not corrected by carrying out the differentiation protocol in the presence of an artificial extracellular matrix. These results demonstrate that the \u201cfull\u2010length\u201d C\/EBP\u03b2 LAP isoform is the predominant C\/EBP\u03b2 protein isoform expressed in mouse mammary gland in vivo and mouse mammary epithelial cell cultures in vitro. C\/EBP\u03b2 LIP detected in mammary tumor lysates may result from in vivo production or ex vivo isolation\u2010induced proteolysis of C\/EBP\u03b2 LAP. Ectopic overexpression of C\/EBP\u03b2 LIP (LAP:LIP ratio of \u223c1:1) inhibits mammary epithelial cell differentiation (\u03b2\u2010casein expression). J. Cell. Biochem. 82:357\u2013370, 2001. \u00a9 2001 Wiley\u2010Liss, Inc.<\/jats:p>","DOI":"10.1002\/jcb.1167","type":"journal-article","created":{"date-parts":[[2002,8,25]],"date-time":"2002-08-25T20:41:50Z","timestamp":1030308110000},"page":"357-370","source":"Crossref","is-referenced-by-count":34,"title":["Expression and function of CCAAT\/enhancer binding protein\u03b2 (C\/EBP\u03b2) LAP and LIP isoforms in mouse mammary gland, tumors and cultured mammary epithelial cells"],"prefix":"10.1002","volume":"82","author":[{"given":"L.R.","family":"Dearth","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J.","family":"Hutt","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A.","family":"Sattler","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A.","family":"Gigliotti","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J.","family":"DeWille","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2001,7,30]]},"reference":[{"key":"e_1_2_6_2_1","first-page":"1569","article-title":"Antisense to cyclin D1 inhibits the growth and tumorigenicity of human colon cancer cells","volume":"57","author":"Arber N","year":"1997","journal-title":"Cancer Res"},{"key":"e_1_2_6_3_1","doi-asserted-by":"crossref","first-page":"4353","DOI":"10.1182\/blood.V92.11.4353","article-title":"Autocrine signals control CCAAT\/enhancer binding protein \u03b2 expression, localization, and activity in macrophages","volume":"92","author":"Baer M","year":"1998","journal-title":"Blood"},{"key":"e_1_2_6_4_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M004268200"},{"key":"e_1_2_6_5_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.5.9.1538"},{"key":"e_1_2_6_6_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.10.21.2794"},{"key":"e_1_2_6_7_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.93.1.465"},{"key":"e_1_2_6_8_1","first-page":"3162","article-title":"C\/EBP and the control of phosphoenolpyruvate carboxykinase gene transcription in the liver","volume":"273","author":"Croninger C","year":"1998","journal-title":"J Biol Chem"},{"key":"e_1_2_6_9_1","doi-asserted-by":"publisher","DOI":"10.1128\/MCB.19.1.1"},{"key":"e_1_2_6_10_1","doi-asserted-by":"publisher","DOI":"10.1016\/0092-8674(91)90531-3"},{"key":"e_1_2_6_11_1","unstructured":"DeWilleJW SattlerA LeeJ YuanR.1997.US Army Breast Cancer Research Program 1 506\u2010W."},{"key":"e_1_2_6_12_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.270.30.17962"},{"key":"e_1_2_6_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/(SICI)1097-4652(199802)174:2<232::AID-JCP10>3.0.CO;2-E"},{"key":"e_1_2_6_14_1","doi-asserted-by":"publisher","DOI":"10.1023\/A:1006381906288"},{"key":"e_1_2_6_15_1","doi-asserted-by":"publisher","DOI":"10.1172\/JCI3135"},{"key":"e_1_2_6_16_1","doi-asserted-by":"publisher","DOI":"10.1091\/mbc.9.6.1479"},{"issue":"2","key":"e_1_2_6_17_1","first-page":"123","article-title":"Transcription factors. 1: bZIP proteins","volume":"1","author":"Hurst HC","year":"1994","journal-title":"Protein Profile"},{"key":"e_1_2_6_18_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M004476200"},{"key":"e_1_2_6_19_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.273.44.28545"},{"key":"e_1_2_6_20_1","first-page":"417","article-title":"Extracellular matrix signaling from the cellular membrane skeleton to the nuclear skeleton: a model of gene regulation","volume":"51","author":"Lelievre S","year":"1996","journal-title":"Recent Prog Hor Research"},{"key":"e_1_2_6_21_1","doi-asserted-by":"publisher","DOI":"10.1096\/fasebj.7.9.8330681"},{"key":"e_1_2_6_22_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.273.16.9552"},{"key":"e_1_2_6_23_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.272.10.6291"},{"key":"e_1_2_6_24_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.274.23.16582"},{"key":"e_1_2_6_25_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.8384376"},{"key":"e_1_2_6_26_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.90.17.8219"},{"key":"e_1_2_6_27_1","doi-asserted-by":"publisher","DOI":"10.1002\/(SICI)1097-4652(199609)168:3<559::AID-JCP8>3.0.CO;2-O"},{"key":"e_1_2_6_28_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.7.8.1559"},{"key":"e_1_2_6_29_1","doi-asserted-by":"publisher","DOI":"10.1210\/me.9.9.1223"},{"key":"e_1_2_6_30_1","first-page":"4382","article-title":"Expression of a translationally regulated dominant\u2010negative CCAAT\/enhancer\u2010binding protein \u03b2 isoform and up\u2010regulation of the eukaryotic translation initiation factor 2\u03b1 are correlated with neoplastic transformation of mammary epithelial cells","volume":"56","author":"Raught B","year":"1996","journal-title":"Cancer Res"},{"key":"e_1_2_6_31_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.12.12.1907"},{"key":"e_1_2_6_32_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.6.3.439"},{"key":"e_1_2_6_33_1","first-page":"101","article-title":"Composite response elements mediate hormonal and developmental regulation of milk protein gene expression","volume":"63","author":"Rosen JM","year":"1998","journal-title":"Biochem Soc Symp"},{"key":"e_1_2_6_34_1","first-page":"2675","article-title":"Genetic modulation of neu proto\u2010oncogene\u2010induced mammary tumorigenesis","volume":"58","author":"Rowse GJ","year":"1998","journal-title":"Cancer Res"},{"key":"e_1_2_6_35_1","doi-asserted-by":"publisher","DOI":"10.1042\/bj3340205"},{"key":"e_1_2_6_36_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.12.12.1917"},{"key":"e_1_2_6_37_1","doi-asserted-by":"publisher","DOI":"10.1128\/MCB.17.3.1744"},{"key":"e_1_2_6_38_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.13.17.2231"},{"key":"e_1_2_6_39_1","doi-asserted-by":"publisher","DOI":"10.1128\/MCB.19.3.1695"},{"key":"e_1_2_6_40_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.5.9.1553"},{"key":"e_1_2_6_41_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.9.19.2350"},{"key":"e_1_2_6_42_1","doi-asserted-by":"publisher","DOI":"10.1101\/gad.9.2.168"},{"key":"e_1_2_6_43_1","doi-asserted-by":"publisher","DOI":"10.1093\/jnci\/89.24.1887"},{"key":"e_1_2_6_44_1","first-page":"261","article-title":"A role for CCAAT\/enhancer binding protein \u03b2\u2010liver\u2010enriched inhibitory protein in mammary epithelial cell proliferation","volume":"61","author":"Zahnow CA","year":"2001","journal-title":"Cancer Res"}],"container-title":["Journal of Cellular Biochemistry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fjcb.1167","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jcb.1167","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,16]],"date-time":"2023-10-16T13:45:37Z","timestamp":1697463937000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/jcb.1167"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2001,7,30]]},"references-count":43,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2001,9]]}},"alternative-id":["10.1002\/jcb.1167"],"URL":"https:\/\/doi.org\/10.1002\/jcb.1167","archive":["Portico"],"relation":{},"ISSN":["0730-2312","1097-4644"],"issn-type":[{"value":"0730-2312","type":"print"},{"value":"1097-4644","type":"electronic"}],"subject":[],"published":{"date-parts":[[2001,7,30]]}}}