Isolation and characterization of human orthologs of yeast CCR4-NOT complex subunits

• Published in: Nucleic acids research 2000-02, Vol.28 (3), p.809-817
• Main Authors: Albert, T K, Lemaire, M, van Berkum, N L, Gentz, R, Collart, M A, Timmers, H T
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; CAF1 protein; CALIF protein; CCR4-NOT protein; Cell Cycle Proteins - chemistry; Cell Cycle Proteins - genetics; Cell Cycle Proteins - metabolism; Cell Line; Cloning, Molecular; Conserved Sequence - genetics; Expressed Sequence Tags; Fungal Proteins - genetics; Fungal Proteins - metabolism; Gene Expression Profiling; Genes, Fungal - genetics; Genetic Complementation Test; Humans; Molecular Sequence Data; Mutation - genetics; NOT1 protein; NOT2 protein; NOT3 gene; NOT3 protein; NOT4 gene; NOT4 protein; NOT5 protein; Precipitin Tests; Protein Binding; Proteins; Receptors, CCR4; Receptors, Chemokine; Repressor Proteins - chemistry; Repressor Proteins - genetics; Repressor Proteins - metabolism; Ribonucleases; RNA, Messenger - analysis; RNA, Messenger - genetics; Saccharomyces cerevisiae; Saccharomyces cerevisiae - chemistry; Saccharomyces cerevisiae - cytology; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins; Transcription Factors - chemistry; Transcription Factors - genetics; Transcription Factors - metabolism; Two-Hybrid System Techniques
• ISSN: 1362-4962; 0305-1048; 1362-4962
• DOI: 10.1093/nar/28.3.809

The yeast CCR4-NOT protein complex is a global regulator of RNA polymerase II transcription. It is comprised of yeast NOT1 to NOT5, yeast CCR4 and additional proteins like yeast CAF1. Here we report the isolation of cDNAs encoding human NOT2, NOT3, NOT4 and a CAF1-like factor, CALIF. Analysis of their mRNA levels in different human tissues reveals a common ubiquitous expression pattern. A multitude of two-hybrid interactions among the human cDNAs suggest that their encoded proteins also form a complex in mammalian cells. Functional conservation of these proteins throughout evolution is supported by the observation that the isolated human NOT3 and NOT4 cDNAs can partially com-plement corresponding not mutations in yeast. Interestingly, human CALIF is highly homologous to, although clearly different from, a recently described human CAF1 protein. Conserved interactions of this factor with both NOT and CCR4 proteins and co-immunoprecipitation experiments suggest that CALIF is a bona fide component of the human CCR4-NOT complex.