New gametophyte genes located in the third linkage group (chromosome 3) of rice.

The relative position of the genes black (b), light ocular diaphragm (lod) and aureate (au) for the third linkage group of T. castaneum (Herbst) (Coleoptera, Tenebrionidae) has been determined as b – lod – au. The distances between the various genes vary, depending on the cross. The b++/+ lod au ♂ × + lod au/+ lod au ♀ crosses give the following recombination values: au – lod = 18.32 ± 1.21%; b – lod = 21.05 ± 1.51% and b – au = 37.43 ± 1.27%. The reciprocal crosses give au – lod = 27.67 ± 1.62%; b – lod = 13.97 ± 1.26% and b – au = 39.79 ± 1.78%. For the larger distances encompassed in the b – au region the recombination values in the two sexes were not significantly different. For the shorter b – lod region the recombination values were significantly larger in the females than in the males, while for the adjacent lod – au region the opposite was true. On the basis of the current literature it would appear that the main factors contributing to these sex differences in recombination are the modifiers which are different in the genetic background of the two sexes.

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Genetics of Differences in Pheromonal Hydrocarbons Between Drosophila melanogaster and D. simulans

Genetics ◽

10.1093/genetics/143.1.353 ◽

1996 ◽

Vol 143 (1) ◽

pp. 353-364 ◽

Cited By ~ 3

Author(s):

Jerry A Coyne

Keyword(s):

Drosophila Melanogaster ◽

Sexual Dimorphism ◽

Genetic Analysis ◽

Species Difference ◽

The Other ◽

Chromosome 3 ◽

Apparent Effect ◽

The Third ◽

Hydrocarbon Profile ◽

The Right

Abstract Females of Drosophila melanogaster and its sibling species D. simulans have very different cuticular hydrocarbons, with the former bearing predominantly 7,11-heptacosadiene and the latter 7-tricosene. This difference contributes to reproductive isolation between the species. Genetic analysis shows that this difference maps to only the third chromosome, with the other three chromosomes having no apparent effect. The D. simulans alleles on the left arm of chromosome 3 are largely recessive, allowing us to search for the relevant regions using D. melanogaster deficiencies. At least four nonoverlapping regions of this arm have large effects on the hydrocarbon profile, implying that several genes on this arm are responsible for the species difference. Because the right arm of chromosome 3 also affects the hydrocarbon profile, a minimum of five genes appear to be involved. The large effect of the third chromosome on hydrocarbons has also been reported in the hybridization between D. simulans and its closer relative D. sechellia, implying either an evolutionaly convergence or the retention in D. sechllia of an ancestral sexual dimorphism.

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Genetic studies on flagellum mutants of Chlamydomonas reinhardii

Genetics Research ◽

10.1017/s0016672300014385 ◽

1972 ◽

Vol 19 (2) ◽

pp. 157-164 ◽

Cited By ~ 12

Author(s):

Anne McVittie

Keyword(s):

Linkage Group ◽

Wild Type ◽

Linkage Groups ◽

Genetic Studies ◽

Chlamydomonas Reinhardii ◽

The Third ◽

Group Ii

SUMMARYEight newly isolated 9 + 0 mutants each mapped at one of the four previously known loci. Short flagellum mutants were at three loci, two of which (pf7 and pf8) were closely linked; the third, pf21, was unlinked to these two and mapped on linkage group II. The long flagellum mutants lf1 and lf2 were on linkage groups II and XII respectively. Mutants pf8A and lf1 were both recessive to wild-type. There was no evidence for non-Mendelian flagellum mutants.

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Linkage of the reindeer and alate prothorax loci and sex differences in recombination frequency in linkage group IX of Tribolium castaneum

Canadian Journal of Genetics and Cytology ◽

10.1139/g85-041 ◽

1985 ◽

Vol 27 (3) ◽

pp. 276-278

Author(s):

Peter S. Dawson ◽

Kelly L. Berends

Keyword(s):

Sex Differences ◽

Linkage Group ◽

Tribolium Castaneum ◽

Autosomal Dominant ◽

Recombination Frequency ◽

Flour Beetle ◽

The Third ◽

Dominant Mutant

Reindeer (Rd), an autosomal dominant mutant in the flour beetle, Tribolium castaneum, is located in linkage group IX. Recombination between Rd and alate prothorax occurs more frequently in males than in females. Linkage group IX appears to be the third linkage group for which recombination frequency is greater in males for one region and in females for another region of the chromosome.Key words: Tribolium, linkage.

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The Third Replicon of Members of the Burkholderia cepacia Complex, Plasmid pC3, Plays a Role in Stress Tolerance

Applied and Environmental Microbiology ◽

10.1128/aem.03330-13 ◽

2013 ◽

Vol 80 (4) ◽

pp. 1340-1348 ◽

Cited By ~ 23

Author(s):

Kirsty Agnoli ◽

Carmen Frauenknecht ◽

Roman Freitag ◽

Stephan Schwager ◽

Christian Jenul ◽

...

Keyword(s):

Burkholderia Cepacia ◽

Screening Method ◽

Burkholderia Cepacia Complex ◽

Chromosome 3 ◽

Epidemic Strain ◽

Content Type ◽

Pcr Screening ◽

The Third ◽

Content Model ◽

Induced Stresses

ABSTRACTThe metabolically versatileBurkholderia cepaciacomplex (Bcc) occupies a variety of niches, including the plant rhizosphere and the cystic fibrosis lung (where it is often fatal to the patient). Bcc members have multipartite genomes, of which the third replicon, pC3 (previously chromosome 3), has been shown to be a nonessential megaplasmid which confers virulence and both antifungal and proteolytic activity on several strains. In this study, pC3 curing was extended to cover strains of 16 of the 17 members of the Bcc, and the phenotypes conferred by pC3 were determined.B. cenocepaciastrains H111, MCO-3, and HI2424 were previously cured of pC3; however, this had not proved possible in the epidemic strain K56-2. Here, we investigated the mechanism of this unexpected stability and found that efficient toxin-antitoxin systems are responsible for maintaining pC3 of strain K56-2. Identification of these systems allowed neutralization of the toxins and the subsequent deletion of K56-2pC3. The cured strain was found to exhibit reduced antifungal activity and was attenuated in both the zebrafish and theCaenorhabditis elegansmodel of infection. We used a PCR screening method to examine the prevalence of pC3 within 110 Bcc isolates and found that this replicon was absent in only four cases, suggesting evolutionary fixation. It is shown that plasmid pC3 increases the resistance ofB. cenocepaciaH111 to various stresses (oxidative, osmotic, high-temperature, and chlorhexidine-induced stresses), explaining the prevalence of this replicon within the Bcc.

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An Analysis of Polygenes Affecting Wing Shape on Chromosome 3 in Drosophila melanogaster

Genetics ◽

10.1093/genetics/153.2.773 ◽

1999 ◽

Vol 153 (2) ◽

pp. 773-786 ◽

Cited By ~ 11

Author(s):

Kenneth Weber ◽

Robert Eisman ◽

Lisa Morey ◽

April Patty ◽

Joshua Sparks ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Transposable Elements ◽

Wing Shape ◽

The Other ◽

Chromosome 3 ◽

Additive Effects ◽

Data Set ◽

The Third ◽

Isogenic Lines ◽

Negative Interactions

AbstractLoci on the third chromosome of Drosophila melanogaster that affect an index of wing shape were mapped, using recombinant isogenic lines, with transposable elements as markers. Many genes with small subequal effects are dispersed along the whole chromosome. Their alleles act nearly additively in heterozygotes. They have small correlated effects on leg shape, but no detectable effects on halteres. Small negative net interactions occur over most of the chromosome. The data set of 519 recombinant isogenic lines can be explained reasonably well by two models. One model posits an indefinitely large number of loci with no interactions. The other model posits 11 loci with additive effects whose sum equals the total phenotypic range and with large positive and negative interactions that nearly cancel each other.

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Chromosomal regions which control sporulation in Bacillus subtilis

Canadian Journal of Microbiology ◽

10.1139/m69-137 ◽

1969 ◽

Vol 15 (7) ◽

pp. 787-790 ◽

Cited By ~ 6

Author(s):

Marvin Rogolsky

Keyword(s):

Bacillus Subtilis ◽

Linkage Group ◽

Genetic Map ◽

Gene Clusters ◽

Linkage Groups ◽

The Third ◽

The Right

Large quantities of sporulation mutants have been isolated with a variety of mutagens. The genetic sites for asporogeny have been localized on the chromosome of Bacillus subtilis through transduction with phage PBSI. Through these procedures specific portions of the chromosome which are associated with sporulation have been identified. Although asporogenic (Sp−) defects were observed to be scattered throughout the four linkage groups of the genetic map of B. subtilis, only three extensive Sp− linkage groups were identified. The first linkage group of Sp− markers is located at the proximal end of the chromosome between the cys A and ery markers. The second cluster of spore genes mapped to the right of ura, and the third linkage group of spore markers mapped to the left of lys-2. Defects within specific regions of the first and third spore gene clusters obstructed some early products of sporogenesis.

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