期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1993
卷号：90
期号：14
页码：6726-6730
DOI：10.1073/pnas.90.14.6726
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A lambda gt11 cDNA library of chicken embryo fibroblasts was screened with biotinylated Jun protein to identify Jun-binding clones. Eight such clones were isolated; one contains a gene referred to as jif-1 that is homologous to the putative tumor suppressor gene QM. jif-1 codes for a protein of 25 kDa that binds to the leucine zipper of viral and cellular Jun. The Jif-1 protein also binds to itself. Jif-1 does not contain a leucine zipper, and it does not bind to the 12-O-tetradecanoylphorbol 13-acetate response element DNA sequence. Complex formation of Jif-1 with Jun inhibits DNA binding and reduces transactivation by Jun. Addition of Fos protein to Jun-Jif-1 complexes restores DNA-binding activity. These observations suggest that Jif-1 is a negative regulator of Jun.
