Leishmania tropica, a unicellular eukaryotic parasite present in North and East Africa, the Middle East, and the Indian subcontinent, has been linked to large outbreaks of cutaneous leishmaniasis in displaced populations in Iraq, Jordan, and Syria. Here, we report the genome sequence of this pathogen and 7,863 identified protein-coding genes, and we show that the majority of clinical isolates p...

Dosage compensation is a chromosome-wide regulatory process that balances X-chromosome gene expression between males and females that have different complements. Recent advances have clarified the molecular nature of the Caenorhabditis elegans sex-determination signal, which tallies X-chromosome number relative to the ploidy and controls both the choice of sexual fate and the process of dosage ...

We show that a functional component of the C. elegans mitotic machinery regulates X chromosome gene expression. This protein, MIX-1, is a member of the dosage compensation complex that associates specifically with hermaphrodite X chromosomes to reduce their gene expression during interphase. MIX-1 also associates with all mitotic chromosomes to ensure their proper segregation. Both dosage compe...

We report that gene dosage, or the ratio of nuclei from two cell types fused to form a heterokaryon, affects the time course of differentiation-specific gene expression. The rate of appearance of the human muscle antigen, 5.1H11, is significantly faster in heterokaryons with equal or near-equal numbers of mouse muscle and human fibroblast nuclei than in heterokaryons with increased numbers of n...

In many diploid species, sex determination is linked to a pair of sex chromosomes that evolved from a pair of autosomes. In theseorganisms, thedegenerationof thesex-limitedYorWchromosomecausesa reduction ingenedose in theheterogametic sex forX-orZ-linked genes. Variations in gene dose are detrimental for large chromosomal regions when they span dosage-sensitive genes, andmany organi...

objective: alpha-thalassemia is one of the most prevalent hemoglobin disorders in the world and it is a common hereditary condition caused by deletion of one or more α-globin genes. common α-thalassemia deletions like 3.7 kb, 4.2 kb, 20.5 kb and med can be detected by multiplex pcr. there are, however, some unknown deletions that can not be detected by the mentioned method or even by direct dna...

Some insight into the developmental basis for imprinting specific genes during the evolution of mammals can be gained from conventional gene 'knockout' studies. However, the consequences of full loss of function are often wide-ranging and may obscure the critical, dosage-related phenotype. This review focuses on transgenic techniques employed to alter the dosage of imprinted genes, including th...

Gene-specific and chromosome-wide mechanisms of transcriptional regulation control development in multicellular organisms. SDC-2, the determinant of hermaphrodite fate in Caenorhabditis elegans, is a paradigm for both modes of regulation. SDC-2 represses transcription of X chromosomes to achieve dosage compensation, and it also represses the male sex-determination gene her-1 to elicit hermaphro...

In Drosophila melanogaster the male specific lethal (MSL) complex is required for upregulation of expression of most X-linked genes in males, thereby achieving X chromosome dosage compensation. The MSL complex is highly enriched across most active X-linked genes with a bias towards the 3' end. Previous studies have shown that gene transcription facilitates MSL complex binding but the type of pr...