A highly conserved Wnt-dependent TCF4 binding site within the proximal enhancer of the anti-myogenic Msx1 gene supports expression within Pax3-expressing limb bud muscle precursor cells

The product of the Msx1 gene is a potent inhibitor of muscle differentiation. Msx1 is expressed in muscle precursor cells of the limb bud that also express Pax3. It is thought that Msx1 may facilitate distal migration by delaying myogenesis in these cells. Despite the role played by Msx1 in inhibiting muscle differentiation, nothing is known of the mechanisms that support the expression of the Msx1 gene within limb bud muscle precursor cells. In the present study we have used a combination of comparative genomics, mouse transgenic analysis, in situ hybridisation and immunohistochemistry to identify a highly conserved and tissue-specific regulatory sub-domain within the previously characterised Msx1 gene proximal enhancer element that supports the expression of the Msx1 gene in Pax3-expressing mouse limb pre-muscle masses. Furthermore, using a combination of in situ hybridisation, in vivo ChIP assay and transgenic explant culture analysis we provide evidence that Msx1 expression in limb bud muscle precursor cells is dependent on the canonical Wnt/TCF signalling pathway that is important in muscle shape formation. The results of these studies provide evidence of a mechanistic link between the Wnt/TCF and the Msx1/Pax3/MyoD pathways within limb bud muscle precursor cells.     

Divergent microsatellite evolution in the human and chimpanzee lineages

Comparison of the complete human genome sequence to one of its closest relatives, the chimpanzee genome, provides a unique opportunity for exploring recent evolutionary events affecting the microsatellites in these species. A simple assumption on microsatellite distribution is that the total length of perfect repeats is constant compared to that of imperfect ones regardless of the repeat sequence. In this paper, we show that this is valid for most of the chimpanzee genome but not for a number of human chromosomes. Our results suggest accelerated evolution of microsatellites in the human genome relative to the chimpanzee lineage.     

眼部真菌感染菌种分布特征

目的分析眼部真菌感染的致病情况和菌种分布特征。方法统计山东省眼科研究所2000～2005年间所有真菌感染病例的培养结果,按照感染部位分类并分析不同菌种的致病情况。结果6年间共有970份真菌培养资料,阳性结果691份,阳性率为71.2%(691/970)。其中角膜溃疡阳性率为86.2%(669/776),镰刀菌占73.2%(490/669);眼内炎阳性率为10.4%(19/182),曲霉菌占68.4%(13/19);泪囊炎阳性率为25.0%(3/12),念珠菌占100.0%(3/3)。结论不同的感染部位常见的真菌菌种不同,镰刀菌是真菌性角膜溃疡的主要致病菌,曲霉菌是真菌性眼内炎的主要致病菌,而念珠菌则是泪囊炎的主要致病菌。     

Fundulus as the premier teleost model in environmental biology: opportunities for new insights using genomics

A strong foundation of basic and applied research documents that the estuarine fish Fundulus heteroclitus and related species are unique laboratory and field models for understanding how individuals and populations interact with their environment. In this paper we summarize an extensive body of work examining the adaptive responses of Fundulus species to environmental conditions, and describe how this research has contributed importantly to our understanding of physiology, gene regulation, toxicology, and ecological and evolutionary genetics of teleosts and other vertebrates. These explorations have reached a critical juncture at which advancement is hindered by the lack of genomic resources for these species. We suggest that a more complete genomics toolbox for F. heteroclitus and related species will permit researchers to exploit the power of this model organism to rapidly advance our understanding of fundamental biological and pathological mechanisms among vertebrates, as well as ecological strategies and evolutionary processes common to all living organisms.     

Automated work-flow for processing high-resolution direct infusion electrospray ionization mass spectral fingerprints

The use of mass spectrometry (MS) is pivotal in analyses of the metabolome and presents a major challenge for subsequent data processing. While the last few years have given new high performance instruments, there has not been a comparable development in data processing. In this paper we discuss an automated data processing pipeline to compare large numbers of fingerprint spectra from direct infusion experiments analyzed by high resolution MS. We describe some of the intriguing problems that have to be addressed, starting with the conversion and pre-processing of the raw data to the final data analysis. Illustrated on the direct infusion analysis (ESI-TOF-MS) of complex mixtures the method exploits the full quality of the high-resolution present in the mass spectra. Although the method is illustrated as a new library search method for high resolution MS, we demonstrate that the output of the preprocessing is applicable to cluster-, discriminant analysis, and related multivariate methods applied directly to mass spectra from direct infusion analysis of crude extracts. This is done to find the relationship between several terverticillate Penicillium species and identify the ions responsible for the segregation.     

Metabolomics standards initiative: ontology working group work in progress

In this article we present the activities of the Ontology Working Group (OWG) under the Metabolomics Standards Initiative (MSI) umbrella. Our endeavour aims to synergise the work of several communities, where independent activities are underway to develop terminologies and databases for metabolomics investigations. We have joined forces to rise to the challenges associated with interpreting and integrating experimental process and data across disparate sources (software and databases, private and public). Our focus is to support the activities of the other MSI working groups by developing a common semantic framework to enable metabolomics-user communities to consistently annotate the experimental process and to enable meaningful exchange of datasets. Our work is accessible via a public webpage and a draft ontology has been posted under the Open Biological Ontology umbrella. At the very outset, we have agreed to minimize duplications across omics domains through extensive liaisons with other communities under the OBO Foundry. This is work in progress and we welcome new participants willing to volunteer their time and expertise to this open effort. See the MSI Ontology Working Group website for a complete list of members and contributors. Web URL:     

The evolutionary and molecular features of the broad-host-range plant pathogen Sclerotinia sclerotiorum

Sclerotinia sclerotiorum is a pathogenic fungus that infects hundreds of plant species, including many of the world's most important crops. Key features of S. sclerotiorum include its extraordinary host range, preference for dicotyledonous plants, relatively slow evolution, and production of protein effectors that are active in multiple host species. Plant resistance to this pathogen is highly complex, typically involving numerous polymorphisms with infinitesimally small effects, which makes resistance breeding a major challenge. Due to its economic significance, S. sclerotiorum has been subjected to a large amount of molecular and evolutionary research. In this updated pathogen profile, we review the evolutionary and molecular features of S. sclerotiorum and discuss avenues for future research into this important species.