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51.
KILLER WHALE PREDATION ON BELUGAS IN COOK INLET, ALASKA: IMPLICATIONS FOR A DEPLETED POPULATION 总被引:1,自引:0,他引:1
Kim E. W. Shelden David J. Rugh BarbaraA. Mahoney Marilyn E. Dahlheim 《Marine Mammal Science》2003,19(3):529-544
Killer whale predation on belugas in Cook Inlet, Alaska, has become a concern since the decline of these belugas was documented during the 1990s. Accordingly, killer whale sightings were compiled from systematic surveys, observer databases, and anecdotal accounts. Killer whales have been relatively common in lower Cook Inlet (at least 100 sightings from 1975 to 2002), but in the upper Inlet, north of Kalgin Island, sightings were infrequent (18 in 27 yr), especially prior to the 1990s. Beach cast beluga carcasses with teeth marks and missing flesh also provided evidence of killer whale predation. Most observed killer whale/beluga interactions were in the upper Inlet. During 11 of 15 observed interactions, belugas were obviously injured or killed, either through direct attacks or indirectly as a result of stranding. Assuming at least one beluga mortality occurred during the other four encounters, we can account for 21 belugas killed between 1985 and 2002. This would suggest a minimum estimate of roughly 1/yr and does not include at least three instances where beluga calves accompanied an adult that was attacked. 相似文献
52.
SHST1 is a sulfate transporter that belongs to a large and diverse family of anion transporters. Little is known about the
structure and function of any member of the family. Site-directed mutagenesis of SHST1 is being used to understand the function
of particular amino acids. We have mutated highly conserved amino acid residues and the results suggest that the first two
helices play an important role in the transport pathway. Furthermore, mutation of equivalent residues to those altered in
human genetic diseases produces deleterious effects in SHST1. These results suggest that there are similarities in the molecular
mechanism of transport throughout the family and the information obtained with SHST1 may be applicable to the entire family. 相似文献
53.
Gautam?Aggarwal EA?Worthey Paul?D?McDonagh Peter?J?MylerEmail author 《BMC bioinformatics》2003,4(1):23
Background
Seattle Biomedical Research Institute (SBRI) as part of the Leishmania Genome Network (LGN) is sequencing chromosomes of the trypanosomatid protozoan species Leishmania major. At SBRI, chromosomal sequence is annotated using a combination of trained and untrained non-consensus gene-prediction algorithms with ARTEMIS, an annotation platform with rich and user-friendly interfaces.Results
Here we describe a methodology used to import results from three different protein-coding gene-prediction algorithms (GLIMMER, TESTCODE and GENESCAN) into the ARTEMIS sequence viewer and annotation tool. Comparison of these methods, along with the CODON USAGE algorithm built into ARTEMIS, shows the importance of combining methods to more accurately annotate the L. major genomic sequence.Conclusion
An improvised and powerful tool for gene prediction has been developed by importing data from widely-used algorithms into an existing annotation platform. This approach is especially fruitful in the Leishmania genome project where there is large proportion of novel genes requiring manual annotation.54.
Charlotte Boyd Roderick C. Hobbs Andr E. Punt Kim E. W. Shelden Christy L. Sims Paul R. Wade 《Marine Mammal Science》2019,35(4):1322-1346
Many small cetacean, sirenian, and pinniped species aggregate in groups of large or variable size. Accurate estimation of group sizes is essential for estimating the abundance and distribution of these species, but is challenging as individuals are highly mobile and only partially visible. We developed a Bayesian approach for estimating group sizes using wide‐angle aerial photographic or video imagery. Our approach accounts for both availability and perception bias, including a new method (analogous to distance sampling) for estimating perception bias due to small image size in wide‐angle images. We demonstrate our approach through an application to aerial survey data for an endangered population of beluga whales (Delphinapterus leucas) in Cook Inlet, Alaska. Our results strengthen understanding of variation in group size estimates and allow for probabilistic statements about the size of detected groups. Aerial surveys are a standard tool for estimating the abundance and distribution of various marine mammal species. The role of aerial photographic and video data in wildlife assessment is expected to increase substantially with the widespread uptake of unmanned aerial vehicle technology. Key aspects of our approach are relevant to group size estimation for a broad range of marine mammal, seabird, other waterfowl, and terrestrial ungulate species. 相似文献
55.
56.
57.
M Ozkan SG Desai Y Zhang DM Stevenson J Beane EA White ML Guerinot LR Lynd 《Journal of industrial microbiology & biotechnology》2001,27(5):275-280
Characteristics of 13 newly isolated thermophilic, anaerobic, and cellulolytic strains were compared with previously described
strains of Clostridium thermocellum: ATCC 27405 and JW20 (ATCC 31549). Colony morphology, antibiotic sensitivity, fermentation end-products, and cellulose degradation
were documented. All 13 strains were sensitive to erythromycin (5 μg/ml) and chloramphenicol (25 μg/ml), and all strains but
one were sensitive to kanamycin (20 μg/ml). Polymerase chain reaction (PCR) amplification using primers based on gene sequences
from C. thermocellum ATCC 27405 was successful for all 13 strains in the case of the hydrogenase gene and 11 strains in the case of phosphotransacetylase/acetate
kinase genes. Ten strains amplified a product of the expected size with primers developed to be specific for C. thermocellum 16SrRNA primers. Two of the 13 strains did not amplify any product with the PCR primers designed for the phosphotransacetylase/acetate
kinase and 16SrRNA primers. A MboI-like GATC- recognizing restriction activity was present in all of the five strains examined. The results of this study have
several positive implications with respect to future development of a transformation system for cellulolytic thermophiles.
Journal of Industrial Microbiology & Biotechnology (2001) 27, 275–280.
Received 12 September 2000/ Accepted in revised form 20 November 2000 相似文献
58.
59.
Restriction of secretory granule motion near the plasma membrane of chromaffin cells 总被引:10,自引:0,他引:10
We used total internal reflection fluorescence microscopy to study quantitatively the motion and distribution of secretory granules near the plasma membrane (PM) of living bovine chromaffin cells. Within the approximately 300-nm region measurably illuminated by the evanescent field resulting from total internal reflection, granules are preferentially concentrated close to the PM. Granule motion normal to the substrate (the z direction) is much slower than would be expected from free Brownian motion, is strongly restricted over tens of nanometer distances, and tends to reverse directions within 0.5 s. The z-direction diffusion coefficients of granules decrease continuously by two orders of magnitude within less than a granule diameter of the PM as granules approach the PM. These analyses suggest that a system of tethers or a heterogeneous matrix severely limits granule motion in the immediate vicinity of the PM. Transient expression of the light chains of tetanus toxin and botulinum toxin A did not disrupt the restricted motion of granules near the PM, indicating that SNARE proteins SNAP-25 and VAMP are not necessary for the decreased mobility. However, the lack of functional SNAREs on the plasma or granule membranes in such cells reduces the time that some granules spend immediately adjacent to the PM. 相似文献
60.
Interaction between pyrin and the apoptotic speck protein (ASC) modulates ASC-induced apoptosis 总被引:5,自引:0,他引:5
Richards N Schaner P Diaz A Stuckey J Shelden E Wadhwa A Gumucio DL 《The Journal of biological chemistry》2001,276(42):39320-39329
Patients with familial Mediterranean fever suffer sporadic inflammatory attacks characterized by fever and intense pain (in joints, abdomen, or chest). Pyrin, the product of the MEFV locus, is a cytosolic protein whose function is unknown. Using pyrin as a "bait" to probe a yeast two-hybrid library made from neutrophil cDNA, we isolated apoptotic speck protein containing a caspase recruitment domain (CARD) (ASC), a proapoptotic protein that induces the formation of large cytosolic "specks" in transfected cells. We found that when HeLa cells are transfected with ASC, specks are formed. After co-transfection of cells with ASC plus wild type pyrin, an increase in speck-positive cells is found, and speck-positive cells show increased survival. Immunofluorescence studies show that pyrin co-localizes with ASC in specks. Speck localization requires exon 1 of pyrin, but exon 1 alone of pyrin does not result in an increase in the number of specks. Exon 1 of pyrin and exon 1 of ASC show 42% sequence similarity and resemble death domain-related structures in modeling studies. These findings link pyrin to apoptosis pathways and suggest that the modulation of cell survival may be a component of the pathophysiology of familial Mediterranean fever. 相似文献