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Biomedical subjects

B Brenig

Publications and source records attributed to B Brenig.

At least 19 recordsLinked to original sources
PubMed2001

A whole genome scan for differences in recombination rates among three Bos taurus breeds.

Twenty paternal half-sib families of a granddaughter design were genotyped for 265 genetic markers, most of them microsatellites. These were 16 Holstein families, 3 Simmental families, and 1 Brown Swiss family. The number of sires per breed was 872, 170, and 32, respectively. Two-point recombination rates were estimated both jointly for all breeds and each single breed separately. Of 1168 marker intervals, 865 provided estimates for at least two breeds. Differences between breeds were tested by likelihood ratio tests. Four marker intervals, representing three genomic regions on BTA19, BTA24, and BTA27, show a significant impact of the breed at a false discovery rate of 0.23 and indicate a genetic component of observed heterogeneity of recombination. The variability of recombination rates between cattle breeds might not be a common feature of the whole genome, but rather might be restricted to certain chromosomal segments. Thus, attention should be paid to heterogeneities when pooling data of such regions from different breeds.

Animals↗
PubMed2001

cDNA cloning and physical mapping of porcine 3 beta-hydroxysteroid dehydrogenase/Delta 5-Delta 4 isomerase.

The 3 beta-hydroxysteroid dehydrogenase/Delta 5-Delta 4-isomerase (3 beta-HSD) enzymes are essential for the biosynthesis of steroid hormones. The 3 beta-HSD gene family has been reported to encode for different isoenzymes which function either as dehydrogenase/isomerase or as reductase. The 3 beta-HSD enzymes are involved in the formation of the pheromone androstenone (5 alpha-androst-16-ene-3-one) which contributes to the unpleasant odour present in the meat of uncastrated boars. An reverse-transcription-polymerase chain reaction (RT-PCR) probe from porcine testicular tissue of a 3 beta-HSD enzyme was used to screen a porcine adipose tissue cDNA library. Both strands of the positive clones were sequenced and the putative coding sequence of 1122 nucleotides encodes 374 amino acids. Comparison of the putative open reading frame with the bovine and the human type I homologues revealed 85.6 and 79.3% identity, respectively. Fluorescence in situ hybridization (FISH) was performed with a labelled PAC clone containing the gene of interest. The 3 beta-HSD gene was mapped to the porcine chromosome 4q16-4q21 which is in accordance with the comparative gene map.

Amino Acid Sequence↗
PubMed2001

Characterization and chromosome assignment of the canine gamma-sarcoglycan gene (SGCG) to CFA 25q21-->q23.

Mutations in the gene for gamma-sarcoglycan (SGCG) located on HSA 13q12 are responsible for limb girdle muscular dystrophy (LGMD2C) in human. Here we report the cloning of the canine SGCG gene together with its genomic structure and several intragenic polymorphisms. The coding part of the canine SGCG contains seven exons spanning at least 70 kb of genomic DNA. The chromosome assignment of the canine SGCG gene to CFA 25q21-->q23 confirms that the canine syntenic group 10 corresponds to CFA 25 and also supports the findings of human-canine reciprocal chromosome painting.

Animals↗
PubMed2001

Molecular characterization and chromosome assignment of the porcine gene COX7A1 coding for the muscle specific cytochrome c oxidase subunit VIIa-M.

The COX7A1 gene encodes a heart- and muscle-specific isoform of the subunit VIIA of cytochrome c oxidase, which is the last component of the mitochondrial electron transfer chain. Cloning and characterization of the porcine COX7A1 gene revealed a highly conserved organization with respect to other mammalian COX7A1 orthologs. The porcine gene consists of four exons spanning approximately 1.5 kb and codes for a peptide of 80 amino acids. The COX7A1 gene showed no variation between pigs from different breeds. The gene was assigned by FISH and RH-mapping to SSC 6q1.1-->q1.2 which is in agreement with previously established comparative maps.

Animals↗
PubMed2001

Molecular characterization and chromosome assignment of the porcine gene for leukemia inhibitory factor LIF.

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine involved in early conceptus development in pig. We isolated a PAC clone containing the porcine LIF gene and determined the complete DNA sequence of the gene, which spans about 6.3 kb and consists of five exons including three alternative first exons (1D, 1M, 1T) spliced onto common second and third exons. The LIF-D transcript encodes a protein of 202 amino acids sharing 87, 84, and 78% identity with respectively human, ovine, and murine leukemia inhibitory factors. The LIF-M and LIF-T transcripts both encode a truncated protein of 158 amino acids. Two SNP markers within untranslated regions of the LIF cDNA were identified. One SNP is located in the 5'-UTR of the alternative exon 1T while the other SNP is located in the 3'-UTR of exon 3. Based on fluorescence in situ hybridization and radiation hybrid mapping, the porcine LIF gene was assigned to chromosome 14q2.1-->q2.2.

Alleles↗
PubMed2001

Characterization and comparative mapping of the porcine CTSL gene indicates a novel synteny between HSA9q21-->q22 and SSC10q11-->q12.

Cathepsin L (CTSL) is a lysosomal cysteine protease with potent elastase and collagenase activities. Its high activity in the uterine lumen during the period of placental attachment has led to speculation that CTSL may play an important role during embryonic implantation in the pig. Cathepsins have also been implicated in blastocyst implantation in other species like cat, rat and man. We isolated a PAC clone containing the porcine CTSL gene and determined the complete DNA sequence of the gene, which spans about 5.6 kb and consists of eight exons. The CTSL transcript encodes a primary peptide of 334 amino acids sharing 73-78% identity with other mammalian cathepsin L precursor proteins. Based on fluorescence in situ hybridization and radiation hybrid mapping, the porcine CTSL gene was assigned to chromosome 10q11--> q12.

Amino Acid Sequence↗
PubMed2000

Molecular analysis and chromosomal assignment of the canine CALC-I/alpha-CGRP gene.

We have isolated a recombinant phage harboring the canine CALC-I/alpha-CGRP gene. The gene spans a region of approx. 5.3 kb and consists of six exons with sizes ranging from 95 bp (exon 2) and 494 bp (exon 4). By alternative splicing, two transcripts with ORFs of 390 and 384 nt are generated. These encode either the 32-amino acid-long hormone calcitonin (CALC) or the neurotransmitter calcitonin gene-related peptide (alpha-CGRP) with a length of 37 amino acids after proteolytic processing of precursor molecules. The canine calcitonin precursor consists of 130 amino acids with a molecular mass of 14.05 kDa and a statistical pI of 8.0, whereas the deduced alpha-CGRP precursor harbors 128 amino acids with a molecular mass of 13.87 kDa and a statistical pI of 8.6. Both polypeptides have a common N-terminal region of 76 amino acids that is encoded by exons 2 and 3 and separated by different eight (CALC) or six (alpha-CGRP) amino acid spacers from the biologically active polypeptide. The CALC-I/alpha-CGRP gene is a member of the calcitonin gene family and was assigned to chromosome CFA 16q25.1. A comparative analysis of different dog breeds revealed a breed-specific allelic d(CAGGAG)-hexanucleotide expansion in exon 3. This expansion results in an elongation of the common N-terminal region by two amino acids (glutamine-glutamic acid) and alters the molecular mass to 14.31 kDa (pI 7.9) and 14.13 kDa (pI 8.5) of the calcitonin and alpha-CGRP precursor, respectively.

Alternative Splicing↗
PubMed2000

Genomic organization of the dog dystroglycan gene DAG1 locus on chromosome 20q15.1-q15.2.

Dystroglycan is a laminin binding protein, which provides a structural link between the subsarcolemmal cytoskeleton and the extracellular matrix. It is also involved in the organization of basement membranes. So far the genomic organization of the dystroglycan gene DAG1 has not been completely investigated. Here we report the cloning and sequencing of 162 kb of dog genomic DNA containing the complete approximately 71-kb canine DAG1 gene, which consists of three exons, with the translation start codon located in exon 2. Its 2679-nucleotide ORF encodes a polypeptide of 892 amino acids, which is highly similar to human, rabbit, and bovine orthologs. To further characterize the dog DAG1 gene we determined the transcription start site and several naturally occurring polymorphisms, which partially result in amino acid substitutions of the dystroglycan protein. The dog DAG1 gene was assigned to chromosome 20q15.1-q15.2 by FISH analysis. The analysis of the entire reported sequence revealed that the genes for aminomethyltransferase (AMT), bassoon (BSN), TCTA (T-cell leukemia translocation-associated) gene, and an as yet uncharacterized protein are located very close to the DAG1 gene. Therefore, this study defines a novel syntenic region among dog chromosome 20q15, human chromosome 3p21, and murine chromosome 9F.

Animals↗
PubMed2000

Cloning, structural organization, and chromosomal assignment of the porcine c-fos proto-oncogene, FOS.

The complete porcine c-fos proto-oncogene (FOS) with flanking regions was cloned and sequenced. FOS consists of four exons at amino acids 1-47, 48-131, 132-167, and 168-380 and includes all the typical motifs of the fos proto-oncogene. The promoter contains consensus sequences for CRE, SRE, CaRE, and the E-Box, as well as an AP-1 site. Homologies between human and swine were between 89.7% and 96.3% in the exons. Based on somatic cell hybrid panel screening and known homologies between swine chromosome 7 and human chromosome 14, the porcine c-fos gene was assigned to chromosome 7q23.

Animals↗
PubMed2000

Genomic structures and sequences of two closely linked genes (AMT, TCTA) on dog chromosome 20q15.1-->q15.2.

Analysis of genomic sequence from canine chromosome 20q15.1-->q15.2 revealed the presence of two closely linked genes. The two genes represent the corresponding canine orthologs of human aminomethyltransferase (AMT) and the human T-cell leukemia translocation associated (TCTA) gene. Aminomethyltransferase or glycine cleavage system T-protein is an important enzyme in glycine metabolism. The reported canine AMT gene spans 5 kb and consists of nine exons. It encodes a protein of 403 amino acids with 88% identity to human aminomethyltransferase. Human TCTA is located on 3p21 near the breakpoint of a t(1;3) translocation observed in some cancer cell lines. The 4-kb canine TCTA gene consists of three exons and probably represents a pseudogene. It is located adjacent to AMT and very close to DAG1 and BSN.

Aminomethyltransferase↗