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R J Bell - One of the best experts on this subject based on the ideXlab platform.
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A malathion resistance gene associated with increased life span of the rusty grain beetle, Cryptolestes ferrugineus (Coleoptera: Cucujidae).
The journals of gerontology. Series A Biological sciences and medical sciences, 1995Co-Authors: N D White, R J BellAbstract:The life span of the rusty grain beetle, Cryptolestes ferrugineus, was determined at 30 degrees C, 75% relative humidity (RH) for virgin and mated adults of a malathion-resistant Strain (BC6RR), a malathion-susceptible Strain (SS), the F1 progeny of a cross between resistant females and susceptible males (RS), and an Outbred Strain (GV). The BC6RR Strain was derived from the SS Strain by incorporating the malathion resistance gene into the susceptible genome with six backcrosses and recovery of heterozygous resistant F1 adults between crosses. The mean life span of virgin, malathion-resistant adults (BC6RR and RS) was 37 weeks; the mean life span of virgin, susceptible adults (SS and GV) was 32 weeks. Resistant virgin adults lived significantly longer (15-16%) than susceptible virgin adults, and mated resistant adults lived significantly longer (3-20%) than mated susceptible adults (p < .05). Since C. ferrugineus has a relatively long reproductive period and females with the longest life spans produce the most offspring, life span can be considered an important component of fitness in this insect. The malathion resistance gene did not reduce fitness, and this gene or genes closely linked to it may be responsible for increasing life span in C. ferrugineus.
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Effect of temperature, food density and sub-lethal exposure to malathion on aging in Cryptolestes ferrugineus (Stephens) (Coleoptera: Cucujidae)
Journal of Stored Products Research, 1994Co-Authors: Noel D.g. White, R J BellAbstract:Abstract The lifespan of an inbred Strain (SS) and an Outbred Strain (GV) of Cryptolestes ferrugineus (Stephens) was determined at several different environmental conditions, and the reproductive capability of adults of the SS Strain kept as isolated virgins until the age of 30 weeks or greater was determined. The developmental period of immature stages reared individually in separate gelatin capsules containing ground wheat plus wheat germ was inversely correlated with temperature and ranged from 22 days at 35°C to 71 days at 22°C. At constant temperatures of 25, 30 and 35°C the lifespan of both Strains was inversely correlated with temperature. Mean adult lifespan ranged from 22 weeks at 35°C to 41 weeks at 22°C for the SS Strain, and from 24 weeks at 35°C to 50 weeks at 22°C for the GV Strain. On a temperature schedule starting at 30°C, decreasing in steps to 5°C, then increasing in steps to 25°C, the mean adult lifespan of each Strain was more than 40% longer than it was on a temperature schedule starting at 22°C, decreasing to 5°C, then increasing to 25°C, although the overall weighted means of both temperature treatments were similar. Beetles of both Strains lived longer on ground wheat plus wheat germ than on whole kernels of wheat that had the seed coats over the germs removed. Exposure to malathion-treated wheat that killed 24% of the population did not shorten the lifespans of survivors. Significant numbers of old adults were able to reproduce: 8 of 10 30-week-old male/female pairs aged at 30°C produced offspring; 2 of 10 one-year-old male/female pairs aged on the temperature schedule starting at 30°C, decreasing to 5°C, then increasing to 25°C, produced offspring.
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Effects of mating status, sex ratio, and population density on longevity and offspring production of Cryptolestes ferrugineus (Stephens) (Coleoptera: Cucujidae).
Experimental gerontology, 1993Co-Authors: N.d.g. White, R J BellAbstract:Abstract The life span and reproductive rate of the rusty grain beetle, Cryptolestes ferrugineus (Stephens), were determined at different adult densities and sex ratios at 30 ± 1°C, 75 ± 5% relative humidity (RH), and with feed consisting of ground wheat plus wheat germ (4:1, w/w). The mean life spans of adult beetles were 32 weeks for adults individually isolated in separate vials, 22 to 25 weeks for adults of different Strains kept one male and one female per vial, 24 weeks for a group of 30 virgin females together in one vial, 13 weeks for a group of 30 virgin males together in one vial, 14 weeks for groups with 10 males and 20 females per vial, 13 weeks for groups with 15 males and 15 females per vial, and 12 weeks for groups with 20 males and 10 females per vial. When kept one adult per vial, males and females had similar life spans; when kept one male and one female per vial, males lived longer; when kept in groups of 30 per vial females lived longer, except in the group which had a sex ratio of two males to one female; in this group life spans of males and females were the same. Females in separate vials with one male produced mean numbers of offspring ranging from 389 for an inbred homozygous malathion-resistant Strain to 514 for an Outbred Strain (genetically variable: GV). GV train females in vials which had 10 males and 20 females produced a mean of 97 offspring, GV Strain females in vials which had 15 males and 15 females produced a mean of 146 offspring, and GV Strain females in vials which had 20 males and 10 females produced a mean of 216 offspring. The results of this study and similar studies on other insect species suggest that the life span of this insect is inversely related to the rate at which it expends energy and to injury incurred during copulation, and that oviposition rate decreases as the density of larvae and female adults increases.
Daniel Pomp - One of the best experts on this subject based on the ideXlab platform.
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a novel intronic snp in the myosin heavy polypeptide 4 gene is responsible for the mini muscle phenotype characterized by major reduction in hindlimb muscle mass in mice
Genetics, 2013Co-Authors: Scott A Kelly, Timothy A Bell, Sarah R Selitsky, Ryan J Buus, Kunjie Hua, George M Weinstock, Theodore Garland, Fernando Pardomanuel De Villena, Daniel PompAbstract:Replicated artificial selection for high levels of voluntary wheel running in an Outbred Strain of mice favored an autosomal recessive allele whose primary phenotypic effect is a 50% reduction in hindlimb muscle mass. Within the High Runner (HR) lines of mice, the numerous pleiotropic effects (e.g., larger hearts, reduced total body mass and fat mass, longer hindlimb bones) of this hypothesized adaptive allele include functional characteristics that facilitate high levels of voluntary wheel running (e.g., doubling of mass-specific muscle aerobic capacity, increased fatigue resistance of isolated muscles, longer hindlimb bones). Previously, we created a backcross population suitable for mapping the responsible locus. We phenotypically characterized the population and mapped the Minimsc locus to a 2.6-Mb interval on MMU11 a region containing ~100 known or predicted genes. Here, we present a novel strategy to identify the genetic variant causing the mini-muscle phenotype. Using high-density genotyping and whole-genome sequencing of key backcross individuals and HR mice with and without the mini-muscle mutation, from both recent and historical generations of the HR lines, we show that a SNP representing a C to T transition located in a 709 bp intron between exons 11 and 12 of the Myosin, heavy polypeptide 4, skeletal muscle gene ( Myh4 ; position 67,244,850 on MMU11; assembly, Dec. 2011, GRCm38/mm10; ENSMUSG00000057003) is responsible for the mini-muscle phenotype, Myh4 Minimsc . Using next generation sequencing, our approach can be extended to identify causative mutations arising in mouse inbred lines and thus offers a great avenue to overcome one of the most challenging steps in quantitative genetics.
Matthias Laska - One of the best experts on this subject based on the ideXlab platform.
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Advance Access publication June 29, 2015 Original Article Olfactory Discrimination Learning in an Outbred and an Inbred Strain of Mice
2016Co-Authors: Matthias LaskaAbstract:The present study compared olfactory discrimination learning in CD-1 mice, a widely used Outbred Strain of mice with that of C57BL/6J mice, one of the most widely used inbred mouse Strains. Using an automated olfactometer and a standard operant conditioning procedure, I found that CD-1 mice needed 60 trials to reach learning criterion in an initial 2-odor discrimination task. They improved in learning speed in subsequent discrimination tasks in which either the rewarded or the unrewarded stimulus was replaced for a new stimulus. C57BL/6J mice, in contrast, needed 120 trials to reach learning criterion in an initial 2-odor discrimination task and also needed significantly more trials than the CD-1 mice in 3 of the 4 subsequent discrimination tasks. Further, the results showed that discrimination learning performance of both mouse Strains was largely unaffected by the odor stimuli used. The results of the present study demonstrate differences between an Outbred and an inbred Strain of mice with regard to odor discrimination learning, a classical measure of cognitive performance in comparative psychology. Thus, they emphasize the need to be careful with generalizing statements as to cognitive or sensory abilities of Mus musculus when inbred Strains of mice are used. Key words: C57BL/6J mice, CD-1 mice, intramodal transfer tasks, olfactory discrimination learnin
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Olfactory Discrimination Learning in an Outbred and an Inbred Strain of Mice.
Chemical senses, 2015Co-Authors: Matthias LaskaAbstract:The present study compared olfactory discrimination learning in CD-1 mice, a widely used Outbred Strain of mice with that of C57BL/6J mice, one of the most widely used inbred mouse Strains. Using an automated olfactometer and a standard operant conditioning procedure, I found that CD-1 mice needed 60 trials to reach learning criterion in an initial 2-odor discrimination task. They improved in learning speed in subsequent discrimination tasks in which either the rewarded or the unrewarded stimulus was replaced for a new stimulus. C57BL/6J mice, in contrast, needed 120 trials to reach learning criterion in an initial 2-odor discrimination task and also needed significantly more trials than the CD-1 mice in 3 of the 4 subsequent discrimination tasks. Further, the results showed that discrimination learning performance of both mouse Strains was largely unaffected by the odor stimuli used. The results of the present study demonstrate differences between an Outbred and an inbred Strain of mice with regard to odor discrimination learning, a classical measure of cognitive performance in comparative psychology. Thus, they emphasize the need to be careful with generalizing statements as to cognitive or sensory abilities of Mus musculus when inbred Strains of mice are used.
Teruhiko Wakayama - One of the best experts on this subject based on the ideXlab platform.
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production of cloned mice using oocytes derived from icr Outbred Strain
Reproduction, 2017Co-Authors: Yoshiaki Tanabe, Satoshi Kishigami, Sayaka Wakayama, Hiroki Kuwayama, Hiroaki Nagatomo, Masatoshi Ooga, Satoshi Kamimura, Teruhiko WakayamaAbstract:Recently, it has become possible to generate cloned mice using a somatic cell nucleus derived from not only F1 Strains but also inbred Strains. However, to date, all cloned mice have been generated using F1 mouse oocytes as the recipient cytoplasm. Here, we attempted to generate cloned mice from oocytes derived from the ICR-Outbred mouse Strain. Cumulus cell nuclei derived from BDF1 and ICR mouse Strains were injected into enucleated oocytes of both Strains to create four groups. Subsequently, the quality and developmental potential of the cloned embryos were examined. ICR oocytes were more susceptible to damage associated with nuclear injection than BDF1 oocytes, but their activation rate and several epigenetic markers of reconstructed cloned oocytes/embryos were similar to those of BDF1 oocytes. When cloned embryos were cultured for up to 4 days, those derived from ICR oocytes demonstrated a significantly decreased rate of development to the blastocyst stage, irrespective of the nuclear donor mouse Strain. However, when cloned embryos derived from ICR oocytes were transferred to female recipients at the two-cell stage, healthy cloned offspring were obtained at a success rate similar to that using BDF1 oocytes. The ICR mouse Strain is very popular for biological research and less expensive to establish than most other Strains. Thus, the results of this study should promote the study of nuclear reprogramming not only by reducing the cost of experiments but also by allowing us to study the effect of oocyte cytoplasm by comparing it between Strains.
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successful mouse cloning of an Outbred Strain by trichostatin a treatment after somatic nuclear transfer
Journal of Reproduction and Development, 2007Co-Authors: Satoshi Kishigami, Sayaka Wakayama, Kenzo Tokunaga, Nguyen Van Thuan, Takafusa Hikichi, Eiji Mizutani, Hiroshi Ohta, Rinako Suetsugu, Tetsutaro Sata, Teruhiko WakayamaAbstract:Although the somatic cloning technique has been used for numerous applications and basic research of reprogramming in various species, extremely low success rates have plagued this technique for a decade. Further in mice, the "clonable" Strains have been limited to mainly hybrid F1 Strains such as B6D2F1. Recently, we established a new efficient cloning technique using trichostatin A (TSA) which leads to a 2-5 fold increase in success rates for mouse cloning of B6D2F1 cumulus cells. To further test the validity of this TSA cloning technique, we tried to clone the adult ICR mouse, an Outbred Strain, which has never been directly cloned before. Only when TSA was used did we obtain both male and female cloned mice from cumulus and fibroblast cells of adult ICR mice with 4-5% success rates, which is comparable to 5-7% of B6D2F1. Thus, the TSA treatment is the first cloning technique to allow us to successfully clone Outbred mice, demonstrating that this technique not only improves the success rates of cloning from hybrid Strains, but also enables mouse cloning from normally "unclonable" Strains.
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54 SUCCESS OF MOUSE CLONING FROM AN Outbred Strain BY TRICHOSTATIN A TREATMENT AFTER SOMATIC NUCLEAR TRANSFER
Reproduction Fertility and Development, 2007Co-Authors: Satoshi Kishigami, Sayaka Wakayama, Takafusa Hikichi, Eiji Mizutani, Hiroshi Ohta, Rinako Suetsugu, Hong-thuy Bui, N. Van Thuan, Teruhiko WakayamaAbstract:Although the somatic cloning technique has been used for numerous applications and basic research of reprogramming in various species, the extremely low success rates have plagued this technique for a decade. Further, in mice, the clonable Strains have been limited mainly to the hybrid F1 Strains such as B6D2F1. Recently, we have reported a new efficient cloning technique using trichostatin A (TSA) where reconstructed oocytes are activated by 5 mM strontium with 5 nM TSA for 6 h, followed by 3 h of culture in KSOM medium containing the same concentration of TSA. After the TSA treatment, cloned embryos were cultured in KSOM medium without TSA. This TSA treatment leads to a 2–5-fold increase in success rates for mouse cloning of B6D2F1 cumulus cells. In this study, to further test the validity of this TSA cloning technique, we tried to clone the adult ICR mouse, an Outbred Strain, which has never been directly cloned before. Only when TSA was used did we obtain both male and female cloned mice from cumulus and fibroblast cells of adult ICR mice with 4–5% success rates, which is comparable to 6–7% of B6D2F1. Thus, the TSA cloning technique now allows us to successfully clone Outbred mice, demonstrating that this technique not only improves the success rates of cloning from the hybrid Strains but also enables mouse cloning from normally unclonable Strains. Further, our results provide insight into the mechanism underlying why only limited Strains can be cloned using the current standard cloning technique.
Scott A Kelly - One of the best experts on this subject based on the ideXlab platform.
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a novel intronic snp in the myosin heavy polypeptide 4 gene is responsible for the mini muscle phenotype characterized by major reduction in hindlimb muscle mass in mice
Genetics, 2013Co-Authors: Scott A Kelly, Timothy A Bell, Sarah R Selitsky, Ryan J Buus, Kunjie Hua, George M Weinstock, Theodore Garland, Fernando Pardomanuel De Villena, Daniel PompAbstract:Replicated artificial selection for high levels of voluntary wheel running in an Outbred Strain of mice favored an autosomal recessive allele whose primary phenotypic effect is a 50% reduction in hindlimb muscle mass. Within the High Runner (HR) lines of mice, the numerous pleiotropic effects (e.g., larger hearts, reduced total body mass and fat mass, longer hindlimb bones) of this hypothesized adaptive allele include functional characteristics that facilitate high levels of voluntary wheel running (e.g., doubling of mass-specific muscle aerobic capacity, increased fatigue resistance of isolated muscles, longer hindlimb bones). Previously, we created a backcross population suitable for mapping the responsible locus. We phenotypically characterized the population and mapped the Minimsc locus to a 2.6-Mb interval on MMU11 a region containing ~100 known or predicted genes. Here, we present a novel strategy to identify the genetic variant causing the mini-muscle phenotype. Using high-density genotyping and whole-genome sequencing of key backcross individuals and HR mice with and without the mini-muscle mutation, from both recent and historical generations of the HR lines, we show that a SNP representing a C to T transition located in a 709 bp intron between exons 11 and 12 of the Myosin, heavy polypeptide 4, skeletal muscle gene ( Myh4 ; position 67,244,850 on MMU11; assembly, Dec. 2011, GRCm38/mm10; ENSMUSG00000057003) is responsible for the mini-muscle phenotype, Myh4 Minimsc . Using next generation sequencing, our approach can be extended to identify causative mutations arising in mouse inbred lines and thus offers a great avenue to overcome one of the most challenging steps in quantitative genetics.
