Project description:RNA-seq of lymphoblastoid cells from a family of individuals (one of which has Trisomy 21) was used to determine the molecular origin of dosage compensation in Trisomy 21.
Project description:GRO-seq of lymphoblastoid cells from a family of individuals (one of which has Trisomy 21) was used to determine the molecular origin of dosage compensation in Trisomy 21.
Project description:Dosage compensation was referred as an equalized X chromosome gene expression between males and females in Drosophila. And inverse dosage effects, produced by genomic imbalance, are believed to account for this modulated expression. Here we made a global expression comparison of trisomy 2L with on extra copy of chromosome 2 long arm to normal diploid with two copies of 2L with high throughput RNA-sequencing. We want to test how about the gene expression pattern changes in those comparisons, including the genes on varied chromosome 2 long arm, some other autosomal genes except chromosome 2L and X chromosome genes. Dosage compensation with an expression level similar to normal diploid and inverse dosage effects should be detected. Comapare the global expression of trisomy 2L samples with the normal diploids Collected the females and males from trisomy 2L and Cantons and performed RNA-seq
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
Project description:Dosage compensation was referred as an equalized X chromosome gene expression between males and females in Drosophila. And inverse dosage effects, produced by genomic imbalance, are believed to account for this modulated expression. Here we made a global expression comparison of trisomy 2L with on extra copy of chromosome 2 long arm to normal diploid with two copies of 2L with high throughput RNA-sequencing. We want to test how about the gene expression pattern changes in those comparisons, including the genes on varied chromosome 2 long arm, some other autosomal genes except chromosome 2L and X chromosome genes. Dosage compensation with an expression level similar to normal diploid and inverse dosage effects should be detected.