Nearly all women diagnosed with ovarian cancer receive combination chemotherapy including cis- or carboplatin. Despite high initial response rates, resistance to cisplatin develops in roughly one-third of women during primary treatment and in all women treated for recurrent disease. ICAT coupled with tandem MS is a quantitative proteomic technique for high throughput protein expression profiling of complex protein mixtures.
View Article and Find Full Text PDFDifferent experimental technologies measure different aspects of a system and to differing depth and breadth. High-throughput assays have inherently high false-positive and false-negative rates. Moreover, each technology includes systematic biases of a different nature.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 2005
The integration of data from multiple global assays is essential to understanding dynamic spatiotemporal interactions within cells. In a companion paper, we reported a data integration methodology, designated Pointillist, that can handle multiple data types from technologies with different noise characteristics. Here we demonstrate its application to the integration of 18 data sets relating to galactose utilization in yeast.
View Article and Find Full Text PDFInterleukin 17 (IL-17) has been linked to autoimmune diseases, although its regulation and function have remained unclear. Here we have evaluated in vitro and in vivo the requirements for the differentiation of naive CD4 T cells into effector T helper cells that produce IL-17. This process required the costimulatory molecules CD28 and ICOS but was independent of the cytokines and transcription factors required for T helper type 1 or type 2 differentiation.
View Article and Find Full Text PDFJ Exp Zool B Mol Dev Evol
January 2006
While the highly consistent gene order and axial colinear patterns of expression seem to be a feature of vertebrate hox gene clusters, this pattern may be less well conserved across the rest of the bilaterians. We report the first deuterostome instance of an intact hox cluster with a unique gene order where the paralog groups are not expressed in a sequential manner. The finished sequence from BAC clones from the genome of the sea urchin, Strongylocentrotus purpuratus, reveals a gene order wherein the anterior genes (Hox1, Hox2 and Hox3) lie nearest the posterior genes in the cluster such that the most 3' gene is Hox5.
View Article and Find Full Text PDFWe present a robust and general method for the identification and relative quantification of phosphorylation sites in complex protein mixtures. It is based on a new chemical derivatization strategy using a dendrimer as a soluble polymer support and tandem mass spectrometry (MS/MS). In a single step, phosphorylated peptides are covalently conjugated to a dendrimer in a reaction catalyzed by carbodiimide and imidazole.
View Article and Find Full Text PDFEvidence of the existence of major prostate cancer (PC)-susceptibility genes has been provided by multiple segregation analyses. Although genomewide screens have been performed in over a dozen independent studies, few chromosomal regions have been consistently identified as regions of interest. One of the major difficulties is genetic heterogeneity, possibly due to multiple, incompletely penetrant PC-susceptibility genes.
View Article and Find Full Text PDFThe complete sequences of Takifugu Toll-like receptor (TLR) loci and gene predictions from many draft genomes enable comprehensive molecular phylogenetic analysis. Strong selective pressure for recognition of and response to pathogen-associated molecular patterns has maintained a largely unchanging TLR recognition in all vertebrates. There are six major families of vertebrate TLRs.
View Article and Find Full Text PDFHomo sapiens possess several trypsinogen or trypsinogen-like genes of which three (PRSS1, PRSS2, and PRSS3) produce functional trypsins in the digestive tract. PRSS1 and PRSS2 are located on chromosome 7q35, while PRSS3 is found on chromosome 9p13. Here, we report a variation of the theme of new gene creation by duplication: the PRSS3 gene was formed by segmental duplications originating from chromosomes 7q35 and 11q24.
View Article and Find Full Text PDFProstate cancer is initially responsive to androgen ablation therapy and progresses to androgen-unresponsive states that are refractory to treatment. The mechanism of this transition is unknown. A systems approach to disease begins with the quantitative delineation of the informational elements (mRNAs and proteins) in various disease states.
View Article and Find Full Text PDFBMP, PTEN and Wnt/beta-catenin pathways are the three signaling pathways that control normal development and regeneration of the intestine, and contribute to intestinal polyposis when aberrant inactivation or activation occurs in each of these pathways. Using genetic targeting of BMPR1A in mice, we show that inactivation of BMP signaling results in multiple polyps due to an increased number of crypts and stem cells, accompanied by enhanced Wnt signaling in all proliferating intestine cells. However the increased transcriptional activity of Wnt effecter protein, beta-catenin, is found primarily in intestine stem cells (ISCs).
View Article and Find Full Text PDFProstate carcinoma is the most common cancer of western men and is a markedly heterogeneous disease. The aim of this study was to identify signatures of differentially expressed genes in prostate cancer using DNA microarray technology, evaluating expression profiles in matched pairs of benign and malignant tissue. Samples were collected from 33 radical prostatectomies, and 52 specimens were included, representing 29 histologically verified primary tumours, 19 paired samples of malignant and benign tissue, and 4 non-paired benign tissue samples.
View Article and Find Full Text PDFA method for the spatially selective biofunctionalization of silicon micro- and nanostructures is reported, and results are presented for both single-crystal silicon (111) or (100) surfaces. An electroactive monolayer of hydroquinone was formed on the surface of H-terminated silicon working electrodes via an olefin reaction with UV-generated surface radicals. Molecules presenting either cyclopentadiene or a thiol group can be immobilized onto the regions where the hydroquinone has been oxidized.
View Article and Find Full Text PDFBackground: The runt domain transcription factors are key regulators of developmental processes in bilaterians, involved both in cell proliferation and differentiation, and their disruption usually leads to disease. Three runt domain genes have been described in each vertebrate genome (the RUNX gene family), but only one in other chordates. Therefore, the common ancestor of vertebrates has been thought to have had a single runt domain gene.
View Article and Find Full Text PDFWe report the complete sequence of the 4,274,642-bp genome of Haloarcula marismortui, a halophilic archaeal isolate from the Dead Sea. The genome is organized into nine circular replicons of varying G+C compositions ranging from 54% to 62%. Comparison of the genome architectures of Halobacterium sp.
View Article and Find Full Text PDFSystems approaches to disease are grounded in the idea that disease-perturbed protein and gene regulatory networks differ from their normal counterparts; we have been pursuing the possibility that these differences may be reflected by multiparameter measurements of the blood. Such concepts are transforming current diagnostic and therapeutic approaches to medicine and, together with new technologies, will enable a predictive and preventive medicine that will lead to personalized medicine.
View Article and Find Full Text PDFbeta-Catenin is a central effector of Wnt signaling in embryonic and stem cell development and in tumorigenesis. Here, through a mass spectrometric analysis of a beta-catenin protein complex, we identified 12 proteins as putative beta-catenin interactors. We show that one of them, 14-3-3zeta, enhances beta-catenin-dependent transcription by maintaining a high level of beta-catenin protein in the cytoplasm.
View Article and Find Full Text PDFBackground: Large fractions of all fully sequenced genomes code for proteins of unknown function. Annotating these proteins of unknown function remains a critical bottleneck for systems biology and is crucial to understanding the biological relevance of genome-wide changes in mRNA and protein expression, protein-protein and protein-DNA interactions. The work reported here demonstrates that de novo structure prediction is now a viable option for providing general function information for many proteins of unknown function.
View Article and Find Full Text PDFUsing DNA microarrays together with quantitative proteomic techniques (ICAT reagents, two-dimensional DIGE, and MS), we evaluated the correlation of mRNA and protein levels in two hematopoietic cell lines representing distinct stages of myeloid differentiation, as well as in the livers of mice treated for different periods of time with three different peroxisome proliferative activated receptor agonists. We observe that the differential expression of mRNA (up or down) can capture at most 40% of the variation of protein expression. Although the overall pattern of protein expression is similar to that of mRNA expression, the incongruent expression between mRNAs and proteins emphasize the importance of posttranscriptional regulatory mechanisms in cellular development or perturbation that can be unveiled only through integrated analyses of both proteins and mRNAs.
View Article and Find Full Text PDFBackground: LNCaP and its derivative cell lines, which include C4-2 (and the related C4-2B) and CL1, are used as models of prostate cancer. Unlike LNCaP, the other cell lines show features of progressed disease such as metastatic capability and hormone independence. Analyses were done to determine if C4-2 or CL1 cells were selected from pre-existent subpopulations in LNCaP.
View Article and Find Full Text PDFWe report a remarkably high UV-radiation resistance in the extremely halophilic archaeon Halobacterium NRC-1 withstanding up to 110 J/m2 with no loss of viability. Gene knockout analysis in two putative photolyase-like genes (phr1 and phr2) implicated only phr2 in photoreactivation. The UV-response was further characterized by analyzing simultaneously, along with gene function and protein interactions inferred through comparative genomics approaches, mRNA changes for all 2400 genes during light and dark repair.
View Article and Find Full Text PDFThe emergence of systems biology is bringing forth a new set of challenges for advancing science and technology. Defining ways of studying biological systems on a global level, integrating large and disparate data types, and dealing with the infrastructural changes necessary to carry out systems biology, are just a few of the extraordinary tasks of this growing discipline. Despite these challenges, the impact of systems biology will be far-reaching, and significant progress has already been made.
View Article and Find Full Text PDFResults from over a dozen prostate cancer susceptibility genome-wide scans, encompassing some 1,500 hereditary prostate cancer families, indicate that prostate cancer is an extremely heterogeneous disease with multiple loci contributing to overall susceptibility. In an attempt to reduce locus heterogeneity, we performed a genomewide linkage scan for prostate cancer susceptibility genes with 36 Jewish families, which represent a stratification of hereditary prostate cancer families with potentially increased locus homogeneity. The 36 Jewish families represent a combined dataset of 17 Jewish families from the Fred Hutchinson Cancer Research Center-based Prostate Cancer Genetic Research Study dataset and 19 Ashkenazi Jewish families collected at Johns Hopkins University.
View Article and Find Full Text PDFSystems biology is the iterative and integrative study of biological systems as systems in response to perturbations. It is founded on hypotheses formalized in models built from the results of global functional genomics analyses of the complexity of the genome, transcriptome, proteome, metabolome, etc. Its implementation by cross-disciplinary teams in a standardized mode under quality assurance should allow accessing the small variations of the large number of elements determining functioning of biological systems.
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