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1.
Michael F. Seldin Lawrence A. D'Hoostelaere Alfred D. Steinberg Yumiko Saga Herbert C. Morse III 《Immunogenetics》1987,26(1-2):74-78
Allelic variants of Ly-5 in inbred commensal and other natural populations of mice were analyzed by patterns of restriction fragment length polymorphisms (RFLP) and Southern hybridization using an Ly-5 cDNA probe and by cell-surface staining with a panel of antibodies directed against polymorphic and nonpolymorphic Ly-5 determinants. New Ly-5 alleles were defined by RFLPs generated by both Eco RI and Bam HI restriction enzyme digests. The Mus musculus subspecies and other species within the genus Mus showed a strong correlation between allelic variants defined by restriction enzymes and serologic specificities. The data also suggest the conservation of the Ly-5 gene throughout the genus Mus. 相似文献
2.
Demonstration of up-regulated IL 2 receptor expression on an in vitro cloned BCL1 subline 总被引:1,自引:0,他引:1
K Nakanishi T Hashimoto K Hiroishi K Matsui T Yoshimoto H C Morse J Furuyama T Hamaoka K Higashino W E Paul 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(6):1817-1825
We have established BCL1 CL-3 cells capable of responding to B15-TRF and interleukin 2 (IL 2). This clone has both high affinity and low affinity receptors for IL 2 (IL 2R), but IL 2 by itself did not stimulate either proliferation or immunoglobulin (Ig) secretion. B15-TRF, which possesses both growth and differentiation activity, causes an increase in size of CL-3 cells and renders CL-3 cells responsive to IL 2, including an increased expression of IL 2R (eight-fold to 10-fold) and the differentiation of CL-3 cells into Ig secretion (60 to 80% of cultured cells). CL-3 cells pretreated with B15-TRF for 12 hr become competent to respond to IL 2 by up-regulation of IL 2R within 12 hr. In contrast CL-3 cells pretreated with IL 2 for 12 hr required 24 hr B15-TRF stimulation to result in IL 2R up-regulation. Thus the ordered action of B15-TRF and IL 2 is the most effective operational pathway for the up-regulation of IL 2R. This IL 2-mediated IL 2R up-regulation and induction of Ig synthesis depends upon the concentration of IL 2 in the culture. Both responses seem to be caused by IL 2 molecules bound to high affinity IL 2R. However, the possibility of involvement of low affinity IL 2R can not be vigorously excluded. In fact the level of IL 2 required for a response is far higher than that needed for activated T cell proliferation. This cloned BCL1 subline promises to be a useful tool for studying the regulation and mechanisms of B cell responses. 相似文献
3.
A field study was conducted on freshly reclaimed surface-mined area to determine response of sericea lespedeza (Lespedeza cuneata [Dumont] G. Don.) to delayed rhizobial inoculation. Soybeans (Glycine max L.) were used as a control legume. Plots were inoculated with spray applications of rhizobial suspensions at seeding, cotyledon stage or second trifoliate leaf stage, or not inoculated. Starter N at 0, 10 or 20 kg ha?1 was applied preplant in a factorial arrangement with inoculation timings.G. max. was grown for 92 days andL. cuneata for 121 days. Starter N increased plant growth and total shoot N in both species. However, % shoot N was found to increase only inL. cuneata. Delaying inoculation had no significant effect upon total shoot N or % shoot N accumulation inL. cuneata. Inoculation ofG. max at planting produced greater plant growth and N accumulation than delayed inoculation treatments. Application of inoculum as a surface spray appeared to be an effective method for delayed inoculation as evidenced by nodule formation. Lack of increased plant growth, regardless of time of inoculation, suggests that delayed inoculation does not improve establishment and growth ofL. cuneata in minesoil. 相似文献
4.
Masahiko Makino Wendy F. Davidson Torgny N. Fredrickson Janet W. Hartley Herbert C. Morse III 《Immunogenetics》1991,33(5-6):345-351
Mice of certain strains are highly sensitive to development of a severe immunodeficiency disease following inoculation as adults with LP-BM5 murine leukemia viruses (MuLV) whereas others are extremely resistant. These strain-dependent differences in response to infection have been shown to be genetically determined with resistance to disease being, in general, associated with homozygosity for Fv-1
nand H-2 haplotypes a and d and sensitivity with homozygosity for Fv-1
band other H-2 haplotypes including b, s, and q. The Fv-1
b, H-2
rstrain RIIIS/J (RIIIS) was found to be highly resistant to disease even though B10.RIII(71NS)/J (B10.RIII), also H-2
r, was very sensitive, thus excluding a role for H-2 in the resistance of RIIIS. The characteristics of RIIIS resistance were evaluated in studies of infected (B10.RIII×RIIIS) F1, F2 and reciprocal backcross mice. Resistance to disease was shown to be semidominant and determined by more than one gene, although a preponderant influence of a single gene was suggested. Studies of segregating populations showed that resistance was not associated with or linked to polymorphisms of the V
\complex or genes in proximity to the Emv-2 locus on chromosome 8. However, there was almost complete concordance between absence of disease in infected mice and inhibition of ecotropic virus spread. These results demonstrate that genes other than Fv-1 or H-2 can profoundly influence the development of retrovirus-induced immunodeficiency and replication of ecotropic viruses.Abbreviations MuLV
murine leukemia virus
- MCF
mink cell focus-inducing MuLV
- B6
C57BL/6
- BM5d
the defective virus in LP-BM5 MuLV
- MAIDS
murine acquired immunodeficiency syndrome
- RIIIS
RIIIS/J
- B10.RIII
B10.RIII (71NS)/J
- MLR
mixed lymphocyte reaction
- FACS
fluorescence activated cell sorter 相似文献
5.
6.
D. C. Spaulding D. E. Morse 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,161(5):498-515
Summary The digestive glands of many marine molluscs are rich sources of arylsufatase enzymes which may function in the catabolism of sulfated polysaccharides in the diets of herbivorous species. Arylsulfatases, partially purified from the hepatopancreas of the red abalone, Haliotis rufescens, were investigated with respect to heterogeneity, catalytic requirements, and timing of induction during development. Four hepatopancreatic enzymes were purified from adult animals using a combination of hydrophobic interaction and anion-exchange chromatography. Zymograms of the four partially-purified enzymes produced by electrophoresis under nondenaturing conditions revealed a fifth, relatively more basic isozyme. All four partially-purified enzymes appear to be monomeric, with molecular weights of approximately 43 000 Da each, as measured by gel filtration. The affinities for p-nitrocatechol sulfate, pH optima, and strengths of inhibition by anions displayed by these enzymes are similar to the values reported for other molluscan arylsulfatases. Three of the four enzymes have K
m values between 0.8 and 2.0 mM for p-nitrocatechol sulfate; the remaining enzyme (A2) has a K
m of 6.7 mM. All four enzymes have pH and temperature optima of 5.5 and 45°C, respectively. Three of the four enzymes have-t1/2(50°C) values of 3.5 min; the enzyme A4 has a t1/2 has a t1/2(50°C) of 8.5 min. A monoclonal antibody directed against form A1b does not cross react with any of the other hepatopancreatic arylsulfatases when assayed by Western blot, confirming the structural heterogeneity of the adult enzymes.Total arylsulfatase activity increases in a biphasic manner during early abalone development, with the first increase occurring early in larval maturation. The secoad phase of enzyme expression is dependent upon the induction of settlement and metamorphosis of the competent veliger larvae, strongly suggesting that the expression of arylsulfatase synthesis (and the maturation of the digestive gland, the hepatopancreas) is controlled by genetic events which occur as a result of metamorphosis. Competent veliger larvae express only two arylsulfatase forms, which share many physicochemical and kinetic characteristics with the adult hepatopancreatic enzymes. However, neither of the larval arylsulfatases is recognized by the monoclonal antibody to form A1b from adult hepatopancreas. Endogenous enzyme inhibitor levels in larvae remain constant throughout the period of arylsulfatase induction, and therefore do not contribute to the control of arylsulfatase activity levels during development.These results are the first documentation of the developmental induction of a specific protein(s) in abalone as a result of metamorphosis. The significance of the timing of arylsulfatase expression is discussed in relation to potential physiological substrates and the dietary switching which occurs at metamorphosis. Possible genetic events which are consistent with the observed patterns of expression of these enzymes also are considered.Abbreviations
BSA
bovine serum albumin
-
C
centigrade
-
Da
daltons
-
DEAE
diethylaminoethyl
-
ELISA
enzyme-linked immunosorbent assay
-
FPLC
fast protein and polynucleotide liquid chromatography
-
GABA
-aminobutyric acid
- HAT
hypoxanthine, aminopterin, thymidine
- Hepes
N-(2-Hydroxythyl)piperazine-N'-(2-ethanesulfonic acid)
-
HPLC
high pressure liquid chromatography
-
KBS
Kantor's balanced salt solution
-
K
m
Michaelis constant
-
PBS
phosphate buffered saline
-
R
m
relative mobility
-
RPMI
Roswell Park Memorial Institute
-
SDS
sodium dodecyl sulfate
-
T
time
-
TBS
TRIS buffered saline
-
V
max
maximal velocity 相似文献
7.
Kinetics of enzyme-mediated reduction of lipid soluble nitroxide spin labels by living cells 总被引:2,自引:0,他引:2
Nitroxide spin labels can be reduced to the corresponding hydroxylamines in cells. The selective action of inhibitors, and thermal and chemical inactivation demonstrate that the reduction of nitroxides in cells is an enzymatic or enzyme-mediated process. The kinetics of reduction of doxylstearates are affected by the position of the doxyl moiety along the stearic acid chain. The doxyl moiety of 5-doxylstearate is close to the membrane surface, and its reduction is first order with respect to the nitroxide, whereas the doxyl moieties of 10- and 12-doxylstearate are in the membrane hydrocarbon region and their reduction is a zero-order process. The reduction of 16-doxylstearate which usually has a mixture of first- and zero-order kinetics becomes zero order with addition of an extracellular broadening agent, potassium trioxalatochromiate(III). These results suggest that the rate of reduction of doxyl moieties is controlled by their accessibility to reducing equivalents, i.e., the rate-limiting step for the reduction of the doxyl moiety deep in the membrane is the diffusion of reducing equivalents within or into the membrane. The reduction of doxylstearates in cells is inhibited by rotenone but not antimycin A, cyanide, propyl gallate or SKF-525A. It appears that the reduction of doxylstearates takes place at the level of the ubiquinone in the respiratory chain in mitochondria in these cells. 相似文献
8.
Specificity and mechanism of influence of amino acid residues on hepatic clearance of oligopeptides 总被引:2,自引:0,他引:2
We have investigated the influence of amino acid residues on hepatic clearance of oligopeptides by determining the rate of disappearance (nmol.(min.g liver)-1) of selective oligopeptides from the medium during isolated rat liver perfusion. (a) N terminus: the rate of disappearance of Ala-Leu was greater (p less than 0.01) than those of Gly-Leu, Phe-Leu, and Arg-Leu (208 +/- 13, 135 +/- 13, 116 +/- 12, and 127 +/- 12, respectively). (b) C terminus: the rate of disappearance of Leu-Ala (244 +/- 18) was significantly greater (p less than 0.01) than that of Leu-Gly (145 +/- 16). (c) Number of residues: with each increase in the number of alanine residues (2-4) there was a significant increase in the rate of peptide disappearance, and conversely, with each increase in the number of glycine residues (2-6) there was a significant decrease in the rate of peptide disappearance. Further studies showed no peptide transport by isolated liver plasma membrane vesicles and no significant correlation between the rates of peptide disappearance and hydrolase activities of the perfusion medium but highly significant correlation with hydrolase activity of plasma membrane. We conclude that certain amino acid residues, such as alanine, enhance hepatic clearance of oligopeptides by increasing their affinity as substrates for plasma membrane peptide hydrolases. 相似文献
9.
Characterization of Haemophilus parainfluenzae strains with low-Mr or ladder-like lipopolysaccharides 总被引:2,自引:0,他引:2
Twenty-five Haemophilus parainfluenzae strains were characterized for lipopolysaccharide (LPS) profiles, outer membrane protein profiles, serum sensitivity, plasmid profiles and DNA homology. Seventeen strains produced low-Mr LPS that did not contain O-sidechains, while the remaining eight strains contained ladder-like LPS suggestive of O-repeated units. This is the first time in the genus Haemophilus that LPS with O-repeated groups has been described. The strains producing the different types of LPS could not be distinguished from each other in outer membrane protein profiles or the other characteristics examined. 相似文献
10.
D R Sumner B Mockbee K Morse T Cram M Pitt 《American journal of physical anthropology》1985,68(2):225-232
Non-invasive characterization of limb bone cross-sectional geometry would be useful for biomechanical analyses of skeletal collections. Computed tomography (CT) is potentially the method of choice. Additionally, CT images are suitable for automated analysis. CT is here shown to be both accurate and precise in the analysis of cross-sectional geometry of prehistoric femora. Beam hardening artifacts can be reduced by using a water bath. As the availability of CT for research increases, both bone density and geometry could be determined simultaneously with this method. 相似文献