Characterization of Solt, a novel SoxLZ/Sox6 binding protein expressed in adult mouse testis

• Published in: FEBS letters 2000-09, Vol.481 (2), p.147-151
• Main Authors: Yamashita, Atsushi, Ito, Michihiko, Takamatsu, Nobuhiko, Shiba, Tadayoshi
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Binding Sites; Ca 2+/calmodulin-dependent protein kinase IV; Ca2+/calmodulin-dependent protein kinase IV; Calcium-Calmodulin-Dependent Protein Kinase Type 4; Calcium-Calmodulin-Dependent Protein Kinases - genetics; Calcium-Calmodulin-Dependent Protein Kinases - metabolism; CaMK, Ca2+/calmodulin-dependent protein kinase; CHO Cells; Cricetinae; DNA-Binding Proteins - chemistry; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Enzyme Activation; Fish Proteins; Gene Expression Regulation; Genes, Reporter - genetics; GST, glutathione S-transferase; Herpes Simplex Virus Protein Vmw65 - chemistry; Herpes Simplex Virus Protein Vmw65 - genetics; Herpes Simplex Virus Protein Vmw65 - metabolism; High Mobility Group Proteins - chemistry; High Mobility Group Proteins - genetics; High Mobility Group Proteins - metabolism; HMG box; HMG, high mobility group; HMK, heart muscle kinase; Leucine zipper; Leucine Zippers; LZ, leucine zipper; Male; Mice; Molecular Sequence Data; Mouse testis; Mutation; Organ Specificity; Promoter Regions, Genetic - genetics; Protein Binding; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - metabolism; RNA, Messenger - analysis; RNA, Messenger - genetics; RT-PCR, reverse transcriptase-polymerase chain reaction; Sox; SOX Transcription Factors; SOXD Transcription Factors; Testis - cytology; Testis - metabolism; Transcription Factors; Transfection; Two-Hybrid System Techniques
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(00)01987-6

SoxLZ/Sox6, a member of the Sox protein family, contains a leucine zipper motif in addition to an HMG box, which is its DNA binding domain. Here we have identified a novel SoxLZ/Sox6 binding protein, termed Solt, which we obtained independently using both a far-Western blot and a yeast two-hybrid screen. Like SoxLZ/Sox6 mRNA, Solt mRNA was exclusively expressed in the testis in mouse. Solt contains an unusual leucine zipper, which bound to the leucine zipper region of SoxLZ/Sox6 in vitro. In transient transfection assays in CHO cells with SoxLZ/Sox6 containing the transactivational region of herpes simplex virus VP16, expression of a reporter gene that carries a cis binding region for Sox proteins was significantly enhanced by the co-expression of Solt and Ca 2+/calmodulin-dependent protein kinase IV.