Identification of the COMM-domain containing protein 1 as specific binding partner for the guanine-rich RNA sequence binding factor 1

• Published in: Biochimica et biophysica acta. General subjects Vol. 1864; no. 11; p. 129678
• Main Authors: Dumoulin, Bernhard, Ufer, Christoph, Stehling, Sabine, Heydeck, Dagmar, Kuhn, Hartmut, Sofi, Sajad
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2020
• Subjects: Adaptor Proteins, Signal Transducing - chemistry; Adaptor Proteins, Signal Transducing - metabolism; brain; cDNA libraries; cell senescence; Co-immonoprecipitation; complementary DNA; erythropoiesis; HEK293 Cells; homeostasis; Humans; mitochondria; nucleotide sequences; Poly(A)-Binding Proteins - chemistry; Poly(A)-Binding Proteins - metabolism; precipitin tests; Protein Binding; Protein Interaction Domains and Motifs; Protein Interaction Maps; Protein-protein interaction; protein-protein interactions; RNA; RNA - metabolism; RNA binding proteins; Side directed mutagenesis; two hybrid system techniques; Yeast three-hybrid system; Co-immonoprecipitation; Protein-protein interaction; Side directed mutagenesis; Yeast three-hybrid system; RNA binding proteins
• ISSN: 0304-4165; 1872-8006; 1872-8006
• DOI: 10.1016/j.bbagen.2020.129678

The guanine-rich RNA sequence binding factor 1 (GRSF1) is an RNA-binding protein of the hnRNP H/F family, which has been implicated in erythropoiesis, regulation of the redox homeostasis, embryonic brain development, mitochondrial function and cellular senescence. The molecular basis for GRSF1-RNA interaction has extensively been studied in the past but for the time being GRSF1 binding proteins have not been identified. To search for GRSF1 binding proteins we first employed the yeast two-hybrid system and screened a cDNA library of human fetal brain for potential GRSF1 binding proteins. Subsequently, we explored the protein-protein-interaction of the recombiant proteins, carried out immunoprecipitation experiments to confirm the interaction of the native proteins in living cells and performed truncation studies to identify the protein-binding motif of GRSF1. Using the yeast two-hybrid system we identified the COMM-domain containing protein 1 (COMMD1) as specific GRSF1 binding protein and in vitro truncation studies suggested that COMMD1 interacts with the alanine-rich domain of GRSF1. Co-immunoprecipitation strategies indicated that COMMD1-GRSF1 interaction was RNA independent and also occurred in living cells expressing the two native proteins. In mammalian cells the COMM-domain containing protein 1 (COMMD1) specifically interacts with the Ala-rich domain of GRSF1 in an RNA-independent manner. This is the first report describing a specific GRSF1 binding protein. •COMMD1 was identified as specific GRSF1 binding protein.•specific COMMD1-GRSF1 interaction was RNA independent.•COMMD1-GRSF1 interaction was shown for recombinant and native proteins.•the Ala-rich domain of GRSF1 functions as COMMD1 binding motif.