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41.
《Animal : an international journal of animal bioscience》2020,14(6):1120-1127
In order to map quantitative trait loci (QTLs) for allometries of body compositions and metabolic traits in chicken, we phenotypically characterize the allometric growths of multiple body components and metabolic traits relative to BWs using joint allometric scaling models and then establish random regression models (RRMs) to fit genetic effects of markers and minor polygenes derived from the pedigree on the allometric scalings. Prior to statistically inferring the QTLs for the allometric scalings by solving the RRMs, the LASSO technique is adopted to rapidly shrink most of marker genetic effects to zero. Computer simulation analysis confirms the reliability and adaptability of the so-called LASSO-RRM mapping method. In the F2 population constructed by multiple families, we formulate two joint allometric scaling models of body compositions and metabolic traits, in which six of nine body compositions are tested as significant, while six of eight metabolic traits are as significant. For body compositions, a total of 14 QTLs, of which 9 dominant, were detected to be associated with the allometric scalings of drumstick, fat, heart, shank, liver and spleen to BWs; while for metabolic traits, a total of 19 QTLs also including 9 dominant be responsible for the allometries of T4, IGFI, IGFII, GLC, INS, IGR to BWs. The detectable QTLs or highly linked markers can be used to regulate relative growths of the body components and metabolic traits to BWs in marker-assisted breeding of chickens. 相似文献
42.
Future uses of pollen analysis must include plant macrofossils 总被引:8,自引:0,他引:8
43.
Tapas K. Nandi Hridoy R. Bairagya Bishnu P. Mukhopadhyay K. Sekar Dipankar Sukul Asim K. Bera 《Journal of biosciences》2009,34(1):27-34
The role of invariant water molecules in the activity of plant cysteine protease is ubiquitous in nature. On analysing the
11 different Protein DataBank (PDB) structures of plant thiol proteases, the two invariant water molecules W1 and W2 (W220
and W222 in the template 1PPN structure) were observed to form H-bonds with the Ob atom of Asn 175. Extensive energy minimization and molecular dynamics simulation studies up to 2 ns on all the PDB and solvated
structures clearly revealed the involvement of the H-bonding association of the two water molecules in fixing the orientation
of the asparagine residue of the catalytic triad. From this study, it is suggested that H-bonding of the water molecule at
the W1 invariant site better stabilizes the Asn residue at the active site of the catalytic triad. 相似文献
44.
45.
Cheka Kehelpannala Thusitha Rupasinghe Asher Pasha Eddi Esteban Thomas Hennessy David Bradley Berit Ebert Nicholas J. Provart Ute Roessner 《The Plant journal : for cell and molecular biology》2021,107(1):287-302
Mass spectrometry is the predominant analytical tool used in the field of plant lipidomics. However, there are many challenges associated with the mass spectrometric detection and identification of lipids because of the highly complex nature of plant lipids. Studies into lipid biosynthetic pathways, gene functions in lipid metabolism, lipid changes during plant growth and development, and the holistic examination of the role of plant lipids in environmental stress responses are often hindered. Here, we leveraged a robust pipeline that we previously established to extract and analyze lipid profiles of different tissues and developmental stages from the model plant Arabidopsis thaliana. We analyzed seven tissues at several different developmental stages and identified more than 200 lipids from each tissue analyzed. The data were used to create a web-accessible in silico lipid map that has been integrated into an electronic Fluorescent Pictograph (eFP) browser. This in silico library of Arabidopsis lipids allows the visualization and exploration of the distribution and changes of lipid levels across selected developmental stages. Furthermore, it provides information on the characteristic fragments of lipids and adducts observed in the mass spectrometer and their retention times, which can be used for lipid identification. The Arabidopsis tissue lipid map can be accessed at http://bar.utoronto.ca/efp_arabidopsis_lipid/cgi-bin/efpWeb.cgi . 相似文献
46.
47.
K. Choi M. D. Burow G. Church G. Burow A. H. Paterson C. E. Simpson J. L. Starr 《Journal of nematology》1999,31(3):283-290
Segregation of resistance to Meloidogyne arenaria in six BC₅F₂ peanut breeding populations was examined in greenhouse tests. Chi-square analysis indicated that segregation of resistance was consistent with resistance being conditioned by a single gene in three breeding populations (TP259-3, TP262-3, and TP271-2), whereas two resistance genes may be present in the breeding populations TP259-2, TP263-2, and TP268-3. Nematode development in clonally propagated lines of resistant individuals of TP262-3 and TP263-2 was compared to that of the susceptible cultivar Florunner. Juvenile nematodes readily penetrated roots of all peanut genotypes, but rate of development was slower (P = 0.05) in the resistant genotypes than in Florunner. Host cell necrosis indicative of a hypersensitive response was not consistently observed in resistant genotypes of either population. Three RFLP loci linked to resistance at distances of 4.2 to 11.0 centiMorgans were identified. Resistant and susceptible alleles for RFLP loci R2430E and R2545E were quite distinct and are useful for identifying individuals homozygous for resistance in segregating populations. 相似文献
48.
Primate microbiome research is a quickly growing field with exciting potential for informing our understanding of primate biology, ecology, and evolution as well as host‐microbe interactions more broadly. This introductory essay to a special section of the American Journal of Primatology provides a cross‐sectional snapshot of current activity in these areas by briefly summarizing the diversity of contributed papers and their relationships to key themes in host‐associated microbiome research. It then uses this survey as a foundation for consolidating a set of key research questions to broadly guide future research. It also argues for the importance of methods standardization to facilitate comparative analyses and the identification of generalizable patterns and relationships. While primatology will benefit greatly from the integration of microbial datasets, it is uniquely positioned to address important questions regarding microbiology and macro‐ecology and evolution more generally. We are eager to see where the primate microbiome leads us. 相似文献
49.
Metabolic rate in diapause and nondiapause brown locust eggs correlated with embryonic development 总被引:1,自引:0,他引:1
INNOCENT N. KAMBULE SHIRLEY A. HANRAHAN FRANCES D. DUNCAN 《Physiological Entomology》2011,36(4):299-308
Insects use dormancy to survive adverse conditions. Brown locust Locustana pardalina (Walk.) eggs offer a convenient model to study dormancy (diapause and quiescence), which contributes to their survival under arid conditions. The metabolic rates of developing nondiapause, diapause and quiescent eggs are compared in the present study using closed‐system respirometry. The embryo becomes committed to continue development and hatch or to enter diapause 6 days after the eggs are placed on moist soil. The metabolic rate of nondiapause eggs increases exponentially until hatching, whereas that of diapause eggs is low and stable. The metabolic rate of diapause laboratory eggs (1.9 ± 0.6 µL CO2 mg?1 h?1) is significantly higher than that of field eggs (0.5 ± 0.3 µL CO2 mg?1 h?1), although the ranges of metabolic rate overlap and the embryos are all in late anatrepsis. The metabolic rate of quiescent eggs is similar to that of diapause eggs but decreases with time. Low metabolic rates during arrested development allow eggs to persist over long periods before hatching. 相似文献
50.
Abstract The conformations of the chains constituting the hydrophilic component of alkyl monolayers and bilayers are investigated by performing molecular dynamics atomistic simulations on these systems at different temperatures. Several monitoring techniques are used to reveal the chain conformations, including atom pair radial distribution functions, evolutions of the torsional angles over thousands of timesteps, frequency distributions of the torsionl angles and ‘snapshot’ plots of the atomic configurations. These methods consistently testify to the stability of the trans (fully extended) character of the strain-free alkyl chains up to room temperature. The chains retain much of this conformation even when the layers are compressed by the application of pressure, to which the chains respond by ‘folding’ at the ends attaching them to the substrate planes while maintaining directions which are mainly normal to these planes. A non-zero gap between the layers is also maintained. A pressure of about 50 kbar abruptly causes all motion in the chains to cease, resulting in a highly ordered lattice structure. 相似文献