RESUMO
The male-biased prevalence of certain neurodevelopmental disorders and the sex-biased outcomes associated with stress exposure during gestation have been previously described. Here, we hypothesized that genes distinctively targeted by only one or both homologous proteins highly conserved across therian mammals, SOX3 and SRY, could induce sexual adaptive changes that result in a differential risk for neurodevelopmental disorders. ChIP-seq/chip data showed that SOX3/SRY gene targets were expressed in different brain cell types in mice. We used orthologous human genes in rodent genomes to extend the number of SOX3/SRY set (1,721). These genes were later found to be enriched in five modules of coexpressed genes during the early and mid-gestation periods (FDR < 0.05), independent of sexual hormones. Genes with differential expression (24, p < 0.0001) and methylation (40, p < 0.047) between sexes were overrepresented in this set. Exclusive SOX3 or SRY target genes were more associated with the late gestational and postnatal periods. Using autism as a model sex-biased disorder, the SOX3/SRY set was enriched in autism gene databases (FDR ≤ 0.05), and there were more de novo variations from the male autism spectrum disorder (ASD) samples under the SRY peaks compared to the random peaks (p < 0.024). The comparison of coexpressed networks of SOX3/SRY target genes between male autism and control samples revealed low preservation in gene modules related to stress response (99 genes) and neurogenesis (78 genes). This study provides evidence that while SOX3 is a regulatory mechanism for both sexes, the male-exclusive SRY also plays a role in gene regulation, suggesting a potential mechanism for sex bias in ASD.
Assuntos
Transtornos do Neurodesenvolvimento/genética , Fatores de Transcrição SOXB1/genética , Proteína da Região Y Determinante do Sexo/genética , Animais , Transtorno do Espectro Autista/genética , Proteínas de Ligação a DNA/genética , Bases de Dados Genéticas , Feminino , Regulação da Expressão Gênica/genética , Redes Reguladoras de Genes , Predisposição Genética para Doença , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Risco , Fatores de Transcrição SOXB1/metabolismo , Cromossomos Sexuais/genética , Fatores Sexuais , Proteína da Região Y Determinante do Sexo/metabolismo , Fatores de Transcrição/genéticaRESUMO
Ring chromosomes are present in 1 in 25,000 human fetuses; 99% arise de novo while less than 1% of rings are inherited. This chromosomal rearrangement may arise through a cytogenetic mechanism involving breaks in chromosome arms and fusion of the proximal broken ends, leading to a loss of distal material. Most patient Y ring chromosomes are present in a 45,X/46,X,r(Y) mosaic karyotype; molecular analyses of infertile men have shown that it is not rare to find r(Y) in these patients. However, the clinical spectrum in those cases with a 45,X cell line is broad and depends on the percentage of the monosomic cell line in different tissues. Y chromosome abnormalities and 45,X mosaic karyotypes are often associated with disorders of sex determination. Here, we report a male patient with hypospadias, cryptorchidism and a mosaic karyotype containing a low proportion of 45,X monosomic cells and multiple ring Y chromosomes in peripheral blood. Clinical, surgical, and molecular evidence was sufficient for a diagnosis of mixed gonadal dysgenesis. We suggest that a detailed cytogenetic and molecular analysis should be done in all males with bilateral descended testes and infertility.
Assuntos
Cromossomos Humanos Y/genética , Disgenesia Gonadal Mista/genética , Mosaicismo , Cromossomos em Anel , Núcleo Celular/metabolismo , Centrômero/metabolismo , Criança , Bandeamento Cromossômico , Humanos , Hibridização in Situ Fluorescente , Interfase , Cariotipagem , Masculino , Metáfase , Fenótipo , Proteína da Região Y Determinante do Sexo/metabolismoRESUMO
Mutations of SRY are the cause of 46,XY complete pure gonadal dysgenesis (PGD) in 10-15% of patients. In this study, DNA was isolated and sequenced from blood leukocytes and from paraffin-embedded gonadal tissue in five patients with 46,XY complete PGD. DNA binding capability was analyzed by three different methods. The structure of the full length SRY and its mutant proteins was carried out using a protein molecular model. DNA analysis revealed two mutations and one synonymous polymorphism: in patient #4 a Y96C mutation, and a E156 polymorphism; in patient #5 a S143G mosaic mutation limited to gonadal tissue. We demonstrated, by all methods used, that both mutant proteins reduced SRY DNA binding activity. The three-dimensional structure of SRY suggested that besides the HMG box, the carboxy-terminal region of SRY interacts with DNA. In conclusion, we identified two SRY mutations and a polymorphism in two patients with 46,XY complete PGD, demonstrating the importance of the carboxy-terminal region of SRY in DNA binding activity.
Assuntos
Biologia Computacional , DNA/metabolismo , Disgenesia Gonadal 46 XY/metabolismo , Proteínas Mutantes/metabolismo , Proteína da Região Y Determinante do Sexo/metabolismo , Sequência de Bases , Análise Mutacional de DNA , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Mutantes/genética , Ligação Proteica , Proteína da Região Y Determinante do Sexo/genéticaRESUMO
SRY directs testicular development. It has been suggested that the only high-mobility group (HMG) box of the SRY is important for the function of this protein; however, other studies have suggested that the N- and C-terminal regions are also involved in this process. Herein, we analysed and compared in vitro the DNA-binding activity of the full-length SRY and three mutants (HMG box alone, N-terminal less and C-terminal less SRY proteins). DNA-binding capability was analysed by mobility shift assays, optical density and dissociation constant by using pure non-fusion SRY proteins. The structure of the full-length SRY was carried out using a protein molecular model. The HMG box SRY alone and C-terminal less SRY proteins had a statistically diminished DNA binding in comparison with the full-length SRY. In contrast, the affinity for DNA of the N-terminal less SRY was relatively similar to the full-length SRY. Likewise, three-dimensional structure of the full-length SRY suggested that some residues of the C-terminal region of the SRY interact with DNA. We demonstrate the importance that full-length SRY has, particularly the C-terminal region of the protein, in DNA binding in vitro. Likewise, the affinity of the HMG box alone is clearly reduced when compared with the full-length SRY.