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William Nobis

Publications and source records attributed to William Nobis.

3 recordsLinked to original sources

Structure of the bovine natural resistance associated macrophage protein (NRAMP 1) gene and identification of a novel polymorphism.

The NRAMP 1 gene is a major candidate gene influencing the outcome of infections with intracellular pathogens in numerous species. NRAMP 1 is highly conserved in many mammalian species and the NRAMP 1 gene shows considerable conservation in structure between mice and humans. The association of NRAMP 1 gene polymorphisms with disease in cattle has been limited to a single microsatellite located within the 3'-non coding region of the bovine NRAMP 1 gene. In order to facilitate further studies on this important gene, we now report the nearly complete structure of the bovine NRAMP 1 gene, including sizes and positions of 13 introns relative to the bovine NRAMP 1 gene coding sequence and the DNA sequence of intron-exon junctions. Comparison of the bovine, murine and human NRAMP 1 gene structures revealed a high degree of conservation in intron placement, though the lengths of several introns were less-well conserved. In general, the greatest divergence in intron lengths occurred in regions of the NRAMP 1 gene displaying the lowest coding sequence conservation. In addition, mutations near intron-exon junctions could account for 25 of the 75 total amino acid differences between murine and bovine NRAMP 1. Using information gained through this study, it was possible to rapidly identify a novel polymorphism within the bovine NRAMP 1 gene intron X. This polymorphism was shown by direct DNA sequence analysis to consist of insertion of three guanine nucleotides at positions 37,40 and 98 relative to the intron X start point. Initial scans of several cattle breeds suggest that the two intron X alleles identified here are stable and widespread in the Bos taurus population.

Animals↗

Development of a porcine brain cDNA library, EST database, and microarray resource.

Recent developments in expressed sequence tag (EST) and cDNA microarray technology have had a dramatic impact on the ability of scientists to study responses of thousands of genes to internal and external stimuli. In neurobiology, studies of the human brain have been expanding rapidly by use of functional genomics techniques. To enhance these studies and allow use of a porcine brain model, a normalized porcine brain cDNA library (PBL) has been generated and used as a base for EST discovery and microarray generation. In this report, we discuss initial sequence analysis of 965 clones from this resource. Our data revealed that library normalization successfully reduced the number of clones representing highly abundant cDNA species and overall clone redundancy. Cluster analysis revealed over 800 unique cDNA species representing a redundancy rate for the normalized library of 6.9% compared with 29.4% before normalization. Sequence information, BLAST results, and TIGR cluster matches for these ESTs are publicly available via a web-accessible database (http://nbfgc.msu.edu). A cDNA microarray was created using 877 unique porcine brain EST amplicons spotted in triplicate on glass slides. This microarray was assessed by performing a series of experiments designed to test hybridization efficiency and false-positive rate. Our results indicate that the PBL cDNA microarray is a robust tool for studies of brain gene expression using swine as a model system.

Animals↗

Bioinformatics and high throughput approach to create genomic resources for the study of bovine immunobiology.

The advent of technologies such as real-time reverse transcriptase polymerase chain reaction (RT-PCR) and cDNA microarrays herald a new era in the study of biological systems. In immunobiology, these advances have begun to impact studies of infectious diseases, inflammatory processes, and immune cell function. However, a lack of genetic reagents for domestic and companion animals has precluded widespread application of new technologies to studies in these systems. We have recently described development of cDNA microarrays for studying bovine immunobiology. Although powerful in revealing genes involved in immunological phenomena in cattle, these resources were limited by a lack of genes known to function in immune responses from other species, such as mouse and human. To address this shortcoming, we used a combination of bioinformatics and high throughput RT-PCR to create amplicons representing over 270 bovine genes whose orthologs in other species were known to function in immune responses. Amplified gene segments were prepared from cDNA representing RNA isolated from either unstimulated or concanavalin A (ConA) stimulated peripheral blood mononuclear cells (PBMCs). In total, 276 genes were amplified from cDNA representing unstimulated bovine PBMC RNA or from cDNA representing ConA stimulated bovine PBMC RNA. A web-accessible resource (http://gowhite.ans.msu.edu/public_php/gd-bovine-immunology.php) has been created to assist in dissemination of this novel resource. The web-accessible resource contains information on gene name, the forward and reverse primers used to amplify each segment, expected product size, and if the gene was found in unstimulated PBMCs or only in ConA stimulated PBMCs. Gene names appear as hyperlinks to the Genbank pages representing the bovine gene or expressed sequence tag (EST) used to generate each primer pair.

Animals↗