Myotonic dystrophy (DM) is the most common form of adult muscular dystrophy. DM Type 1 caused by expansion of a CTG repeat in the 3' untranslated region of the dystrophia myotonica-protein kinase (DMPK) gene. In the August 3 Science, Christina Liquori and colleagues from the University of Minnesota report that DM2 is also caused by microsatellite expansion in non-coding sequences (Science 2001, 293:864-867). While characterizing the DM2 locus on chromosome 13q21, Liquori et al. discovered an exp

Toll-like receptors (TLRs) are important for vertebrate recognition of pathogen-associated molecular forms. The receptor TLR9 is involved in the recognition of bacterial DNA by virtue of its unmethylated CpG dinucleotides. In the July 31 Proceedings of the National Academy of Sciences, Bauer et al. show that human TLR9 (hTLR9) confers responsiveness to CpG-DNA and differs from its mouse homologue (mTLR9) in CpG motif recognition (Proc Natl Acad Sci USA 2001, 98:9237-9242). Immunostimulatory CpG

The eed (embryonic ectoderm development) gene is a member of the mouse Polycomb group (Pc-G) and is required for early gastrulation. In the Advance Online issue of Nature Genetics, Jianbo Wang and colleagues from the University of North Carolina define a role for eed in X chromosome inactivation. They analysed trophoblast giant cells in eed-null embryonic deciduas and found developmental defects in eed-null females but not in male embryos. To investigate the role of paternal X inactivation, Wang

In the July 26 ScienceXpress, Heng Zhu and colleagues from Yale University describe the construction of a proteome microarray containing approximately 80% of all yeast proteins (ScienceXpress 2001, 10.1126/science.1062191). They built a high-quality collection of 5800 yeast open reading frames (ORFs), representing 93.5% of all yeast genes. Each ORF was fused to a glutathione-S-transferase (GST)-HisX6 tag and expressed in yeast under the inducible GAL1 promoter. Proteins were spotted at high spat

In the Advance Online issue of Nature Genetics, Andrew Curtis and colleagues from the Institute of Human Genetics in Newcastle, UK, describe a new genetic disease that they have named 'neuroferritinopathy'. The neurological disease is characterized by adult-onset degeneration of the basal ganglia and extrapyramidal dysfunction. Affected individuals live within a 40km radius of the home of the earliest founder, a member of a local family from Cumbria, UK. Curtis et al. performed linkage analysis

The retinoblastoma protein (pRB) is a tumor suppressor protein that can act as a transcriptional repressor, but the mechanisms underlying this function are unclear and controversial. In the July 17 Proceedings of the National Academy of Sciences, Kennedy et al., from the Massachusetts General Hospital Cancer Center, describe the use of a yeast model system to address the mechanism of pRB repression (Proc Natl Acad Sci USA 2001, 98:8720-8725). They expressed a chimeric protein in which the large

The repressor-activator protein 1 (Rap1) binds to [C(1-3)A]n repeats, acts as a transcriptional activator, and represses gene expression at telomeres by binding to the accessory silencing proteins Sir2, Sir3 and Sir4. In the Advance Online Publication of Nature Genetics, Lieb and colleagues, at Stanford University, describe a study to investigate the genome-wide DNA-binding specificity of Rap1 and Sir proteins in vivo (Nature Genetics 2001 DOI:10.1038/ng569). They performed chromatin immunopreci

Synthetic chimeric molecules can be used to target proteins for ubiquitin-dependent degradation.

Streptococcus pneumoniae (pneumococcus) was the bacterial strain used in the historic studies of Avery, MacLeod and McCarty more than half a century ago to demonstrate that DNA is the material of inheritance. The Gram-positive bacterium causes over 3 million infant deaths each year from pneumonia, bacteremia and meningitis. In the July 20 Science, Tettelin and colleagues from The Institute for Genome Research (TIGR) report the complete genome sequence of S. pneumoniae (Science 2001, 293:498-506)

Mitotic segregation of chromosomes depends on correct assembly of the bipolar spindle and mitosis is delayed by the spindle assembly checkpoint (SAC). In the July 19 Nature, Gachet et al., at the National Institute for Medical Research and University College London, describe a different mitotic checkpoint in yeast (Nature 2001, 412:352-355). They investigated the link between organization of the actin cytoskeleton and the cell cycle in the fission yeast Schizosaccharomyces pombe. They synchroniz

Mutations in the human BRCA2 gene are associated with susceptibility to early-onset breast cancer, but it is unclear how the wild-type BRCA2 protein works. In the July 17 Proceedings of the National Academy of Sciences, Xia et al. describe investigation of the role of BRCA2 in DNA repair (Proc Natl Acad Sci USA 2001, 98:8644-8649). They expressed BRCA2 in Capan-1 carcinoma cells, the only human cell line that has non-functional BRCA2. BRCA2 expression increased homologous recombination ten-fold,

The yeast two-hybrid system is one of the most widely used functional genomic tools for studying protein-protein interactions. But transcriptional activators cannot be used as 'bait' proteins in the assay as they can activate the reporter gene, usually used as an indicator of protein interaction, even in the absence of protein interactions. In the July 17 Proceedings of the National Academy of Sciences, Hirst et al. describe a modified two-hybrid assay that is based on transcriptional repression