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71.
Horton R Gibson R Coggill P Miretti M Allcock RJ Almeida J Forbes S Gilbert JG Halls K Harrow JL Hart E Howe K Jackson DK Palmer S Roberts AN Sims S Stewart CA Traherne JA Trevanion S Wilming L Rogers J de Jong PJ Elliott JF Sawcer S Todd JA Trowsdale J Beck S 《Immunogenetics》2008,60(1):1-18
The human major histocompatibility complex (MHC) is contained within about 4 Mb on the short arm of chromosome 6 and is recognised
as the most variable region in the human genome. The primary aim of the MHC Haplotype Project was to provide a comprehensively
annotated reference sequence of a single, human leukocyte antigen-homozygous MHC haplotype and to use it as a basis against
which variations could be assessed from seven other similarly homozygous cell lines, representative of the most common MHC
haplotypes in the European population. Comparison of the haplotype sequences, including four haplotypes not previously analysed,
resulted in the identification of >44,000 variations, both substitutions and indels (insertions and deletions), which have
been submitted to the dbSNP database. The gene annotation uncovered haplotype-specific differences and confirmed the presence
of more than 300 loci, including over 160 protein-coding genes. Combined analysis of the variation and annotation datasets
revealed 122 gene loci with coding substitutions of which 97 were non-synonymous. The haplotype (A3-B7-DR15; PGF cell line)
designated as the new MHC reference sequence, has been incorporated into the human genome assembly (NCBI35 and subsequent
builds), and constitutes the largest single-haplotype sequence of the human genome to date. The extensive variation and annotation
data derived from the analysis of seven further haplotypes have been made publicly available and provide a framework and resource
for future association studies of all MHC-associated diseases and transplant medicine.
Horton and Gibson contributed equally to this work. 相似文献
72.
Functional consequences of cysteine modification in the ligand binding sites of peroxisome proliferator activated receptors by GW9662 总被引:21,自引:0,他引:21
73.
Stephen B. Pyecroft Anne-Maree Pearse Richmond Loh Kate Swift Kathy Belov Nolan Fox Erin Noonan Dane Hayes Alex Hyatt Lingfa Wang David Boyle Jeff Church Debra Middleton Robert Moore 《EcoHealth》2007,4(3):346-351
In the mid 1990s an emerging disease characterised by the development of proliferative lesions around the face of Tasmanian
devils (Sarcophilus harrisii) was observed. A multi-disciplinary approach was adopted to define the condition. Histopathological and transmission electron
microscopic examination combined with immunohistochemistry help define Devil Facial Tumour Disease (DFTD) as a neoplastic
condition of cells of neuroendocrine origin. Cytogenetic analysis of neoplastic tissue revealed it to be markedly different
from normal devil tissue and having a consistent karyotype across all tumours examined. Combined with evidence for Major histocompatability
(MHC) gene analysis there is significant evidence to confirm the tumour is a transmissible neoplasm. 相似文献
74.
Laura H. Graham Jeff Bolling Gary Miller Nancy Pratt‐Hawkes Sharon Joseph 《Zoo biology》2002,21(4):403-408
Circulating patterns of progesterone and luteinizing hormone (LH) in the elephant have been well characterized, and routine monitoring of these hormones is now viewed as a valuable tool for making informed decisions about the reproductive management of elephants in captivity. Currently, LH monitoring in elephants is done with radio‐immunoassays (RIAs); unfortunately, the use of radioactive materials in RIAs limits their application to institutions with laboratory facilities equipped for the storage and disposal of radioactive waste. Enzyme‐immunoassays (EIAs) offer an inexpensive and more zoo‐friendly alternative to RIA. This work reports on an EIA capable of quantifying circulating LH in African elephants. The EIA employs a biotin label and microtiter plates coated with goat anti‐mouse gamma globulin. LH surges in African elephants (n=3) increased fivefold over baseline concentrations (1.00±0.1 ng/ml vs. 0.2±0.1 ng/ml) and occurred 19.3±0.2 days apart. Ovulatory LH surges were associated with an increase in serum progestogens from 4.8±0.4 ng/ml to 11.7±0.4 ng/ml. The ability to quantify reproductive hormones in elephants via EIA is an important step in the process of making endocrine monitoring more accessible to zoos housing these species. Zoo Biol 21:403–408, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
75.
76.
Small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) have been purified from 3 species of orchid in the genus Cymbidium by gel filtration followed by preparative sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and electroelution. The samples were subjected to amino acid composition analysis and partial N-terminal amino acid sequencing. The sequencing data clearly confirm that one of the species examined is the hybrid offspring of a cross between the other two. 相似文献
77.
Differential expression of two P5CS genes controlling proline accumulation during salt-stress requires ABA and is regulated by ABA1, ABI1 and AXR2 in Arabidopsis 总被引:13,自引:0,他引:13
78.
Suzanne M. Watt David J. Gilmore Donald Metcalf Stephen P. Cobbold Trang K. Hoang Herman Waldmann 《Journal of cellular physiology》1983,115(1):37-45
A rat monoclonal antibody, YBM/42, directed against mouse leukocyte common antigen, was used for the analysis and separation of hemopoietic progenitor cells from mouse bone marrow and fetal liver. Cells were fractionated on a FACS-II cell sorter and the resulting subpopulations examined for their morphology and ability to form colonies in agar (for day 7 colonies) and methylcellulose (for day 2 erythroid clones). The antibody bound to all leukocytes, including blast cells and day 7 hemopoietic progenitor cells (day 7 colony forming cells, CFC), but not to erythrocytes or nucleated erythroid cells. This antibody can be used to advantage to enrich for early progenitor cells from mouse fetal liver, in which the majority of cells (70%) are nucleated erythroid cells. In day 12 fetal liver, approximately 10% of all cells bind this antibody strongly and, of these approximately 70% are blast cells. Contained within this positive population are 95% of all day 7 CFC. In the most enriched fraction about 20% of the cells formed day 7 colonies. This represents a 25-fold enrichment over unsorted fetal liver. The negative fractions contain 94% of all cells forming erythroid clones (≥8 cells) on day 2 of culture (day 2 CFU-E). In the most enriched fraction, 20% of the cells are day 2 CFU-E. Day 7 CFC can therefore be well separated from day 2 CFU-E, with good recovery of both cell types, by use of a single label. Day 7 colony forming cells were classified as granulocyte (G-CFC), macrophage (M-CFC), mixed granulocyte/macrophage (GM-CFC), pure erythroid (E), or mixed erythroid (Emix). A high enrichment for multipotential cells is achieved and constitues 3–5% of cells in the most enriched fraction. Most types of day 7 CFC could not be separated with YMB/42, but GM-CFC and M-CFC exhibit a broader distribution than the other CFC with regard to fluorescence intensity. This implicit heterogeneity in GM-CFC and M-CFC is further substantiated by the finding that myeloid progenitors in the different FACS fractions also share a differential reactivity to different sources of growth factors. 相似文献
79.
80.
Maitreyi Sur Brian Woodbridge Todd C. Esque Jim R. Belthoff Peter H. Bloom Robert N. Fisher Kathleen Longshore Kenneth E. Nussear Jeff A. Tracey Melissa A. Braham Todd E. Katzner 《Ecology and evolution》2021,11(12):7905
- A central theme for conservation is understanding how animals differentially use, and are affected by change in, the landscapes they inhabit. However, it has been challenging to develop conservation schemes for habitat‐specific behaviors.
- Here we use behavioral change point analysis to identify behavioral states of golden eagles (Aquila chrysaetos) in the Sonoran and Mojave Deserts of the southwestern United States, and we identify, for each behavioral state, conservation‐relevant habitat associations.
- We modeled behavior using 186,859 GPS points from 48 eagles and identified 2,851 distinct segments comprising four behavioral states. Altitude above ground level (AGL) best differentiated behavioral states, with two clusters of short‐distance movement behaviors characterized by low AGL (state 1 AGL = 14 m (median); state 2 AGL = 11 m) and two associated with longer‐distance movement behaviors and characterized by higher AGL (state 3 AGL = 108 m; state 4 AGL = 450 m).
- Behaviors such as perching and low‐altitude hunting were associated with short‐distance movements in updraft‐poor environments, at higher elevations, and over steeper and more north‐facing terrain. In contrast, medium‐distance movements such as hunting and transiting were over gentle and south‐facing slopes. Long‐distance transiting occurred over the desert habitats that generate the best updraft.
- This information can guide management of this species, and our approach provides a template for behavior‐specific habitat associations for other species of management concern.