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1.
S. M. Kaeppler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(3):384-392
The power to detect QTL using near-isogenic line (NIL) comparisons versus recombinant inbred (RI) populations was assessed.
The power to detect QTL was found to be generally greater when using RI populations than when using NIL contrasts. Power to
detect QTL with NIL contrasts never exceeded that of RI populations when the number of RI lines is maximized relative to replication
of lines for a given number of experimental units. The relative power of NIL contrasts is highest for traits with high heritability
and when a gain in precision is realized due to increased replication of entries. Although NIL populations are generally less
powerful than RI populations of similar size, some practical considerations may enhance the value of these materials. Availability
of NILs allows the genetic effect of a specific chromosome region to be determined by comparing two lines; all RI lines in
a population need to be rescored for each new trait even if the effect of a specific chromosome region is suspected. NIL comparisons
may allow genetic differences to be detected by visual inspection; genetic effects can only be expressed as means and variances
with recombinant inbred populations. In summary, RI populations generally, and in some cases, substantially, provide better
power for QTL detection than NIL comparisons. Practical considerations, however, indicate that many factors need to be considered
when choosing a population structure to meet an experimental objective.
Received: 12 December 1996 / Accepted: 21 March 1997 相似文献
2.
Adrienne L. Kaeppler 《Ethnos》2013,78(1-4):102-128
3.
Dagmar Waberski Anke Döhring Florencia Ardón Nadine Ritter Holm Zerbe Hans-Joachim Schuberth Marion Hewicker-Trautwein Karl Fritz Weitze Ronald HF Hunter 《Acta veterinaria Scandinavica》2006,48(1):13-8
Whole boar semen or seminal plasma has been demonstrated to advance the time of ovulation in gilts. As a means of clarifying
this influence, the contribution of uterine lymphatics and their white cell populations has been examined. After duct visualisation
with Evan's blue, lymph was sampled from a mesometrial vessel in eight pre-ovulatory gilts whose uterine lumen was infused
simultaneously with whole semen in one ligated horn and saline in the contralateral ligated horn. Lymph was collected from
cannulated vessels for periods of up to four hours under general anaesthesia. Thereafter, mesometrial lymph nodes, utero-tubal
junction and uterine wall tissues were sampled. The proportion of nucleated cells in the sampled lymph increased towards the
end of the collection period, but erythrocytes were found in all instances preventing a meaningful differentiation and identification
of leukocytes. Prominent uterine lymph nodes were present in the mesometrium on both sides of the reproductive tract in 7
of 10 gilts. Differences in cellular contents were demonstrated between the side of the tract infused with semen and that
infused with saline control. Two of 4 gilts had lower values for CD4 (Cluster Differentiation) and 3 of 6 gilts higher values
for MHC II (Major Histocompatibility Complex) markers on the side challenged with semen. In contrast, values remained constant
for CD8 but ranged widely for CD18. Immunohistochemical analysis of uterine tissue samples for MHC II+ cells revealed significant
differences (P < 0.05) between the control and semen-treated ligated portions of the horns, as well as between the tissue
sample of uterine wall and that from the utero-tubal junction, but there were no significant differences for CD4+ cells. It
therefore remains plausible that semen-induced cytokines in the uterine lymph undergo counter-current transfer to the ipsilateral
ovary and accelerate the final maturation of pre-ovulatory Graafian follicles. 相似文献
4.
5.
Shovelomics: high throughput phenotyping of maize (Zea mays L.) root architecture in the field 总被引:2,自引:0,他引:2
Samuel Trachsel Shawn M. Kaeppler Kathleen M. Brown Jonathan P. Lynch 《Plant and Soil》2011,341(1-2):75-87
We present a method to visually score 10 root architectural traits of the root crown of an adult maize plant in the field in a few minutes. Phenotypic profiling of three recombinant inbred line (RIL) populations of maize (Zea mays L.; B73xMo17, Oh43xW64a, Ny821xH99) was conducted in 2008 in a silt loam soil in Pennsylvania and in a sandy soil in Wisconsin, and again in 2009 in Pennsylvania. Numbers, angles and branching pattern of crown and brace roots were assessed visually at flowering. Depending on the soil type in which plants were grown, sample processing took from three (sand) to 8 min (silt-loam). Visual measurement of the root crown required 2 min per sample irrespective of the environment. Visual scoring of root crowns gave a reliable estimation of values for root architectural traits as indicated by high correlations between measured and visually scored trait values for numbers (r 2?=?0.46?C0.97), angles (r 2?=?0.66?C0.76), and branching (r 2?=?0.54?C0.88) of brace and crown roots. Based on the visual evaluation of root crown traits it was possible to discriminate between populations. RILs derived from the cross NY821 x H99 generally had the greatest number of roots, the highest branching density and the most shallow root angles, while inbred lines from the cross between OH43 x W64a generally had the steepest root angles. The ranking of genotypes remained the same across environments, emphasizing the suitability of the method to evaluate genotypes across environments. Scoring of brace roots was better correlated with the actual measurements compared to crown roots. The visual evaluation of root architecture will be a valuable tool in tailoring crop root systems to specific environments. 相似文献
6.
Mitchell L. Wise Hassan K. Sreenath Ronald W. Skadsen Heidi F. Kaeppler 《Plant Cell, Tissue and Organ Culture》2009,97(1):81-90
Oats produce a group of secondary metabolites termed avenanthramides (avn). These compounds are biosynthesized through the
action of the enzyme hydroxycinnamoyl CoA: hydroxyanthranilate N-hydroxycinnamoyl transferase (HHT) which catalyzes the condensation of one of several cinnamate CoA thioesters with the amine
functionality of anthranilic acid, 4-hydroxy- or 5-hydroxy-anthranilic acid. In oat leaf tissue the biosynthesis of avenanthramides
appears to result from elicitation by fungal infection. Here we demonstrate the biosynthesis of several avenanthramides in
suspension cultures of oat apical meristem callus tissue. This phenomenon appears as a generalized pathogen response, evidenced
by the production of PR-1 mRNA, in response to elicitation with chitin (poly-N-acetyl glucosamine). The suspension cultures also produce relatively large quantities of avnA and G in response to chitin
elicitation. Under certain culture conditions avnB and C are also produced as well as three additional metabolites tentatively
identified as avnH, O and R. These findings portend the utility of oat suspension culture as a tool for more detailed investigation
of the mechanisms triggering their biosynthesis as well as the factors dictating the particular types of avenanthramides biosynthesized. 相似文献
7.
Qing Li Steven R. Eichten Peter J. Hermanson Virginia M. Zaunbrecher Jawon Song Jennifer Wendt Heidi Rosenbaum Thelma F. Madzima Amy E. Sloan Ji Huang Daniel L. Burgess Todd A. Richmond Karen M. McGinnis Robert B. Meeley Olga N. Danilevskaya Matthew W. Vaughn Shawn M. Kaeppler Jeffrey A. Jeddeloh Nathan M. Springer 《The Plant cell》2014,26(12):4602-4616
DNA methylation can play important roles in the regulation of transposable elements and genes. A collection of mutant alleles for 11 maize (Zea mays) genes predicted to play roles in controlling DNA methylation were isolated through forward- or reverse-genetic approaches. Low-coverage whole-genome bisulfite sequencing and high-coverage sequence-capture bisulfite sequencing were applied to mutant lines to determine context- and locus-specific effects of these mutations on DNA methylation profiles. Plants containing mutant alleles for components of the RNA-directed DNA methylation pathway exhibit loss of CHH methylation at many loci as well as CG and CHG methylation at a small number of loci. Plants containing loss-of-function alleles for chromomethylase (CMT) genes exhibit strong genome-wide reductions in CHG methylation and some locus-specific loss of CHH methylation. In an attempt to identify stocks with stronger reductions in DNA methylation levels than provided by single gene mutations, we performed crosses to create double mutants for the maize CMT3 orthologs, Zmet2 and Zmet5, and for the maize DDM1 orthologs, Chr101 and Chr106. While loss-of-function alleles are viable as single gene mutants, the double mutants were not recovered, suggesting that severe perturbations of the maize methylome may have stronger deleterious phenotypic effects than in Arabidopsis thaliana. 相似文献
8.
9.
Routine utilization of green fluorescent protein as a visual selectable marker for cereal transformation 总被引:2,自引:0,他引:2
Heidi F. Kaeppler A. R. Carlson G. K. Menon 《In vitro cellular & developmental biology. Plant》2001,37(2):120-126
Summary Development of new selectable markers is needed to increase the efficiency and flexibility of plant transformation, and to
overcome drawbacks sometimes associated with use of existing markers. A useful alternative to chemical-based selection systems
would be a system using visual screening to obtain transgenic lines. Investigations were carried out to determine if the green
fluorescent protein (gfp) gene could be utilized alone as a visual screenable marker to produce stably transformed, fertile oat plants. Twelve experiments
were conducted in which gfp-based selection was utilized to obtain routinely stable transgenic lines in oat. A synthetic gfp gene under the control of the maize ubiquitin promoter was delivered into embryogenic oat callus via microprojectile bombardment. Cell clusters (1–3 mm) expressing gfp were visually identified using epifluorescence microscopy and physically isolated approximately 3 wk post-bombardment. Fertile,
gfp-expressing T0 plants were regenerated from 78% of the glowing cell sectors placed on regeneration medium. T0 plants from
55% of the events produced gfp-expressing progeny in a 3∶1 Mendelian ratio. Southern blot and PCR analysis confirmed transgene integration and transmission
to progeny. Expression of gfp did not reduce plant growth or fertility. Transgene copy number and integration patterns were similar to those in transgenic
plants derived from chemical-based selection systems. The mean transformation frequency, based on fertile events obtained
per bombarded plate, was 1.8%. Over 180 independent transgenic oat lines were produced, to date, using only visual screening
for expression of gfp, demonstrating efficiency and repeatability of the selection system.
Mention of a trademark or proprietary product does not constitute a guarantee or warranty by the University of Wisconsin or
the US Department of Agriculture and does not imply its approval to the exclusion of other products that may be suitable. 相似文献
10.
QTL mapping and phenotypic variation for root architectural traits in maize (Zea mays L.) 总被引:1,自引:0,他引:1
Amy L. Burton James M. Johnson Jillian M. Foerster Candice N. Hirsch C. R. Buell Meredith T. Hanlon Shawn M. Kaeppler Kathleen M. Brown Jonathan P. Lynch 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(11):2293-2311