Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Genetic mapping”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,423 records · Page 79Linked to original sources
PubMed1985

Genetic mapping of rpoD implicates the major sigma factor of Bacillus subtilis RNA polymerase in sporulation initiation.

We have mapped the chromosomal locus of rpoD, which encodes the major sigma factor of Bacillus subtilis RNA polymerase. The rpoD locus lay between aroD and lys, tightly linked to dnaE and inseparable from crsA. Marker order in this region was acf-aroD-dnaE-rpoD(crsA)-spoOG-lys. By transformation using cloned donor DNA from the rpoD region, we identified the gene immediately upstream of rpoD as dnaE, which coded for a 62,000 dalton protein essential for DNA replication. Both dnaE and rpoD were transcribed in the same direction, counterclockwise on the chromosome. The gene functions and organization in the rpoD region are thus similar to those of the E. coli sigma operon. We also used transformation to identify crsA47 as a mutation within the sigma coding region itself. The crsA alteration of sigma renders the sporulation process insensitive to glucose catabolite repression, and also restores sporulation ability to strains carrying early-blocked spoOE, spoOF, and spoOK mutations. Thus the major sigma factor and these spoO gene products directly or indirectly affect the same cellular function.

Bacillus subtilis↗
PubMed1988

Genetic mapping of the Escherichia coli gene for the stringent starvation protein and its dispensability for normal cell growth.

To determine its map position, the sSP gene was cloned into plasmid pBR322 and the recombinant plasmid was integrated into the chromosome of a polA mutant at the site of the sSP gene by homologous recombination. The chromosomal location of Ampr was then determined by P1 phage-mediated transduction. Thus, the sSP gene was mapped between gltB and glnF at min 69.5 on the Escherichia coli chromosome. Strains were constructed in which the sSP gene was brought under the control of the lac regulatory system. This indicated that the stringent starvation protein (SSP) is dispensable for growth, at least under normal culture conditions.

Bacterial Proteins↗
PubMed1978

Drosophila hemolymph proteins: purification, characterization, and genetic mapping of larval serum protein 2 in D. melanogaster.

Three of the major protein species present in the hemolymph of Drosophila melanogaster larvae just prior to pupation are absent from second instar larvae but accumulate rapidly during the third instar. This article describes the purification and characterization of one of these, larval serum protein (LSP) 2, using an immunological assay. It is a homohexamer of molecular weight about 450,000, with a polypeptide molecular weight of 78,000--83,000. Fast and slow electrophoretic variants of this protein map between the markers vin and gs, at 36--37 on chromosome 3.

Animals↗
PubMed1983

Genetic mapping and characterization of aldehyde oxidase of Anopheles albimanus (Diptera: Culicidae).

Aldehyde oxidase (Ao) of Anopheles albimanus Wiedemann was mapped on chromosome 3. The sequence is hexokinase-1--19.2 +/- 1.8--stripe--28.3 +/- 2.2--beta-hydroxy acid dehydrogenase--3.6 +/- 0.3--aldehyde oxidase--2.6 +/- 0.4--esterase-8--6.1 +/- 1.9--esterase-4--?--esterase-6 (phosphoglucomutase). Aldehyde oxidase is 26.1 +/- 2.5 from phosphoglucomutase and 27.2 +/- 1.6 from esterase-6. The one-band electromorph of Ao in homozygotes and the three-band type in heterozygotes suggest that the enzyme is a dimer. The isoelectric points of slow and fast allozymes are 5.5 and 4.8, respectively. A variety of electrophoretic techniques was used to determine if the allozymes of Ao can be differentiated on a basis other than mobility. The slow, fast, and hybrid genotypes were analyzed for differences in thermostability, reactivity to thiol reagent, susceptibility to urea denaturation, substrate specificities, and response to chelating agents. The relative effect of p]H on allozymes was tested by varying the pH of the staining buffer over a range of 4-12. No significant differences were detected among allozymes and no additional allelic variations were observed.

Aldehyde Oxidase↗
PubMed1999

Physical and genetic map of the genome of Buchnera, the primary endosymbiont of the pea aphid Acyrthosiphon pisum.

The genome of Buchnera, an endosymbiotic bacterium of the pea aphid Acyrthosiphon pisum, was characterized by pulse-field gel electrophoresis (PFGE) as a circular DNA molecule of 657 kb. The enzymes I-CeuI, CpoI, ApaI, SmaI, NaeI, SacII, MluI, FspI, and NruI were used to cleave the DNA of Buchnera into fragments of suitable size for PFGE analysis. A physical map of the Buchnera genome, including restriction fragments from seven of these enzymes, was constructed using double cutting, partial digestion, and hybridization with linking fragments, and 29 genes and operons were localized on the map. In addition, the genomic map of Buchnera was compared with those of Escherichia coli and Haemophilus influenzae. The gene order in Buchnera is more similar to that of E. coli than to H. influenzae. The dramatic shrinkage of the Buchnera genome compared with those of other members of the closely related Enterobacteriaceae family is discussed in terms of evolution under the influence of the intracellular symbiotic association.

Animals↗
PubMed2002

Genetic mapping of QTLs associated with greenbug resistance and tolerance in Sorghum bicolor.

Ninety three recombinant inbreds of Sorghum bicolor (L. Moench) were derived from a cross between two sorghum lines GBIK and Redlan. This population was used to identify quantitative trait loci (QTLs) for resistance and tolerance to greenbug ( Schizaphids graminum Rondani) Biotypes I and K. One hundred and thirteen loci (38 SSRs and 75 RAPDs) were mapped in 12 linkage groups covering 1,530 cM. In general, nine QTLs were detected affecting both resistance and tolerance to greenbug (GB) Biotypes I and K. The phenotypic variance explained by each QTL ranged from 5.6% to 38.4%. Four SSRs and one RAPD marker were associated with the expression of all resistance and tolerance traits. These markers appear to be linked to biotype non-specific resistance and tolerance genes. Four additional markers were associated with biotype-specific resistance or tolerance traits. The detection of more than one locus for each biotype supports the hypothesis that several regions, which represent different genes, control the expression of resistance and tolerance to greenbug in sorghum. The results can be used for marker-assisted selection and the breeding of greenbug-tolerant sorghum cultivars.

Journal Article↗
PubMed2005

Molecular cloning and genetic mapping of perennial ryegrass casein protein kinase 2 alpha-subunit genes.

The alpha-subunit of the casein protein kinase CK2 has been implicated in both light-regulated and circadian rhythm-controlled plant gene expression, including control of the flowering time. Two putative CK2alpha genes of perennial ryegrass (Lolium perenne L.) have been obtained from a cDNA library constructed with mRNA isolated from cold-acclimated crown tissue. The genomic organisation of the two genes was determined by Southern hybridisation analysis. Primer designs to the Lpck2a-1 and Lpck2a-2 cDNA sequences permitted the amplification of genomic products containing large intron sequences. Amplicon sequence analysis detected single nucleotide polymorphisms (SNPs) within the p150/112 reference mapping population. Validated SNPs, within diagnostic restriction enzyme sites, were used to design cleaved amplified polymorphic sequence (CAPS) assays. The Lpck2a-1 CAPS marker was assigned to perennial ryegrass linkage group (LG) 4 and the Lpck2a-2 CAPS marker was assigned to LG2. The location of the Lpck2a-1 gene locus supports the previous conclusion of conserved synteny between perennial ryegrass LG4, the Triticeae homoeologous group 5L chromosomes and the corresponding segment of rice chromosome 3. Allelic variation at the Lpck2a-1 and Lpck2a-2 gene loci was correlated with phenotypic variation for heading date and winter survival, respectively. SNP polymorphism may be used for the further study of the role of CK2alpha genes in the initiation of reproductive development and winter hardiness in grasses.

Amino Acid Sequence↗
PubMed1996

Physical and genetic map of the mitochondrial genome of Cryphonectria parasitica Ep155.

In the chestnut-blight fungus, Cryphonectria parasitica, a cytoplasmically transmissible (infectious) form of hypovirulence is associated with mitochondrial DNA (mtDNA) mutations that cause respiratory deficiencies. To facilitate the characterization of such mutations, a restriction map including the probable location of 13 genes was constructed for a relatively well-characterized virulent strain of the fungus, Ep155. The physical map is based on the order of all fragments generated by cleavage of the mtDNA by the PstI restriction endonuclease and includes some of the cleavage sites for HindIII, EcoRI, and XbaI. It was constructed from hybridization patterns of cloned mtDNA fragments with Southern blots of mtDNA digested with the four restriction enzymes. On this map, the probable locations of genes commonly found in the mitochondrial genomes of ascomycetes were determined by low-stringency hybridization of cloned Neurospora crassa mitochondrial gene probes to Southern blots of C. parasitica mtDNA. The data indicate that the mtDNA of strain Ep155 is a circular molecule of approximately 157 kbp and ranks among the largest mitochondrial chromosomes observed so far in fungi. The mtDNAs of 11 different C. parasitica isolates range in size from 135 to 157 kbp and in relatedness from 68 to 100 percent, as estimated from restriction-fragment polymorphisms. In addition to the typical mtDNA, the mitochondria of some isolates of the fungus contain double-stranded DNA plasmids consisting of nucleotide sequences not represented in the mtDNA of Ep155.

Ascomycota↗
PubMed2001

High-resolution genetic mapping of the sucrose octaacetate taste aversion (Soa) locus on mouse Chromosome 6.

An acetylated sugar, sucrose octaacetate (SOA), tastes bitter to humans and has an aversive taste to at least some mice and other animals. In mice, taste aversion to SOA depends on allelic variation of a single locus, Soa. Three Soa alleles determine 'taster' (Soa(a)), 'nontaster' (Soa(b)), and 'demitaster' (Soa(c)) phenotypes of taste sensitivity to SOA. Although Soa has been mapped to distal Chromosome (Chr) 6, the limits of the Soa region have not been defined. In this study, mice from congenic strains SW.B6-Soa(b), B6.SW-Soa(a), and C3.SW-Soa(a/c) and from an outbred CFW strain were genotyped with polymorphic markers on Chr 6. In the congenic strains, the limits of introgressed donor fragments were determined. In the outbred mice, linkage disequilibrium and haplotype analyses were conducted. Positions of the markers were further resolved by using radiation hybrid mapping. The results show that the Soa locus is contained in an approximately 1-cM (3.3-4.9 Mb) region including the Prp locus.

Animals↗
PubMed2006

Description and genetic mapping of Polypodia: an X-linked dominant mouse mutant with ectopic caudal limbs and other malformations.

In this report we present a spontaneous mouse mutant, named Polypodia (Ppd), that primarily exhibits ectopic, ventral/caudal limbs and associated pelvic girdle malformation or duplication. Less penetrant features include diphallia, microphthalmia, small kidney, curled or kinked tail, forelimb anomaly, and skin papillae. Ppd mice have a normal karyotype and no large-scale genomic deletions or insertions by BAC-based array comparative genomic hybridization (CGH). Ppd is X-linked dominant with approximately 20% penetrance on the C3H background and maps to X:61.6 Mb-X:71.24 Mb. The limb and a subset of the nonlimb anomalies are similar to those in offspring from retinoic acid-treated dams at E4.5-5.5 and feature overlap with the Disorganization mouse mutant and human patients with ectopic legs. We hypothesize that Ppd affects very early steps in the formation of caudal structures including limb and appendage number. The existence of noncaudal anomalies implies the involvement of Ppd in a broad array of cell fate decisions.

Abnormalities, Multiple↗
PubMed2001

Molecular cloning, genetic mapping, and expression of the mouse Sf3b1 (SAP155) gene for the U2 snRNP component of spliceosome.

SAP155, a subunit of the U2 snRNP, is essential for prespliceosome assembly and splicing catalysis of the major spliceosome. Moreover, the protein has been identified in the minor (U12-dependent) spliceosome. These facts strongly suggest that SAP155 is shared by two distinct complexes owing to its importance in the removal of any type of intron. Here we have isolated a cDNA encoding the 146-kDa mouse homolog, designated Sf3b1. The amino acid sequence of Sf3b1 is very highly conserved among homologs from Schizosaccharomyces pombe (52.4% identity) to human (99.6%), and the C-terminal 825 residues of these Sf3b1 homologs show even higher identities. This C-terminal region shows significant similarity to the PR65 subunit of protein phosphatase 2A, which is composed of 15 tandem repeats of a 39 amino acid sequence. Mouse genome analyses showed Sf3bh1 to be a single-copy gene mapping to the central part of Chromosome (Chr) 1. Northern blot analysis and whole mount in situ hybridization revealed Sf3b1 to be ubiquitously expressed in a variety of adult tissues and mid-gestation embryos.

Amino Acid Sequence↗