SH3GLB, a New Endophilin-Related Protein Family Featuring an SH3 Domain

• Published in: Genomics (San Diego, Calif.) Vol. 71; no. 2; pp. 222 - 234
• Main Authors: Pierrat, Benoit, Simonen, Marjo, Cueto, Maria, Mestan, Jurgen, Ferrigno, Paul, Heim, Jutta
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 15-01-2001; Elsevier
• Subjects: Adaptor Proteins, Signal Transducing; Ageing, cell death; Animals; Apoptosis - drug effects; Base Sequence; Bax protein; bcl-2-Associated X Protein; Biological and medical sciences; Caenorhabditis elegans; Caenorhabditis elegans - genetics; Carrier Proteins - genetics; Carrier Proteins - metabolism; Cell physiology; Cloning, Molecular; Cytoplasm - chemistry; Dimerization; Fundamental and applied biological sciences. Psychology; GRB2 Adaptor Protein; HeLa Cells; Humans; Molecular and cellular biology; Molecular Sequence Data; Multigene Family - genetics; Protein Binding; Proteins - genetics; Proto-Oncogene Proteins - metabolism; Proto-Oncogene Proteins - pharmacology; Proto-Oncogene Proteins c-bcl-2; Pseudogenes; Sequence Alignment; Sequence Homology, Nucleic Acid; SH3 domain GRB2-like endophilin B1; SH3GLB1 gene; src Homology Domains - genetics; Tumor Cells, Cultured; Two-Hybrid System Techniques; Fungi; Genetic mapping; Complementary DNA; Nucleotide sequence; Homology; Molecular interaction; Ascomycetes; Saccharomyces cerevisiae; Aminoacid sequence; Thallophyta; Apoptosis
• ISSN: 0888-7543; 1089-8646
• DOI: 10.1006/geno.2000.6378

A new cDNA encoding a protein of 362 amino acids designated SH3GLB1, for SH3 domain GRB2-like endophilin B1, was identified in a yeast two-hybrid screen devoted to the identification of new partners interacting with the apoptosis inducer Bax. SH3GLB1 shows strong similarities to the SH3 domain-containing proteins of the endophilin family and presumably represents the human homologue of the potential Caenorhabditis elegans SH3 containing-protein identified by systematic translation of the C. elegans genome (GenBank Accession No. U46675). Reversing prey to bait in the yeast screen, a second protein, SH3GLB2, of 395 amino acids showing65% identity to SH3GLB1 was identified as an interactingpartner of SH3GLB1. The discovery of SH3GLB1 itself in the screening with SH3GLB1 as a bait and further mapping experiments demonstrated that a core coiled-coil-type region isrequired for the formation of SH3GLB homo- and/orheterodimers, whereas the SH3 domain is not involved in these interactions. Interestingly, the similarities with the endophilin proteins cover the entire sequence of the SH3GLB family, suggesting a common fold and presumably a common mode of action. Furthermore, SH3GLB members colocalize to the cytoplasmic compartment of the cell together with Bax and are excluded from the nucleus.SH3GLB1 and SH3GLB2 do not significantly influence the onset and time course of Bax-mediated apoptosis in HeLa or 293T cells.