Sox9 transactivation and testicular expression of a novel human gene, KIAA0800.
The Sry and Sox9 sex-determination factors initiate and promote testis differentiation by gene transactivation through similar promoter elements. However, knowledge is limited concerning what genes are regulated by Sry/Sox9 in the testis. Identification and characterization of Sry/Sox9-regulated genes are critical for understanding sexual differentiation. We now demonstrate that a novel human gene, KIAA0800, is preferentially expressed in the testis and is transactivated by Sox9. The KIAA0800 promoter is repressed by an upstream element involving a polyT track and two Alu repeats. Two specific Sox9-bindings sites have been identified in the KIAA0800 promoter by using DNaseI footprinting assays and gel electrophoretic mobility shift assays. Sox9 transactivation of the KIAA0800 promoter appears to be exerted mainly through the relief of promoter repression. Genes homologous to the human KIAA0800 exist in organisms with differentiated sex tissues including mouse, Drosophila, and C. elegans, but not in unicellular organisms, including yeast and bacteria. Further, our recent sequence analysis shows that KIAA0800 protein is 97% identical between human and mouse. Thus, KIAA0800 is a novel Sox9-activated gene that is evolutionarily conserved and potentially involved in sexual differentiation.
Institute for Molecular Virology, St. Louis University Health Sciences Center, 3681 Park Avenue, Missouri 63110, USA. zhaol@slu.edu
Ling-Jun
LJ
Zhao
Shangao
S
Zhang
G
G
Chinnadurai
D020087:Alu Elements / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D017124:Conserved Sequence; D004247:DNA / Q000235:genetics / Q000378:metabolism; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006609:High Mobility Group Proteins / Q000378:metabolism*; D006801:Humans; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D020218:Response Elements / Q000235:genetics; D055758:SOX9 Transcription Factor; D019849:Sex Determination Processes; D012733:Sex Differentiation; D013379:Substrate Specificity; D013737:Testis / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D024363:Transcription Initiation Site; D015533:Transcriptional Activation
D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; C527933:Sox9 protein, mouse; D014157:Transcription Factors; D004247:DNA