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1.
Raj K. Singh Mary F. Ruh Thomas S. Ruh 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,800(1):33-40
In the present study we investigated the binding characteristics of estrogen and antiestrogen-receptor complexes to rabbit uterine chromatin. Activated or nonactivated estrogen receptors were partially purified by DEAE-cellulose chromatography using low (1 mM) or high (10 mM) concentrations of sodium molybdate. Activated [3H]estradiol-receptor complexes showed enhanced binding to chromatin acceptor sites unmasked by 1 M, 4 M and 6 M guanidine hydrochloride. We also examined the chromatin-binding characteristics of the estrogen receptors when bound by the high-affinity triphenylethylene antiestrogen, H1285. The acceptor site activity for the [3H]H1285-receptor complexes was markedly decreased at sites unmasked by 4 M and 6 M guanidine hydrochloride. Further, the nonactivated receptor complexes showed very low binding to deproteinized chromatin. The estrogen-receptor chromatin-acceptor sites were tissue specific and saturable. These chromatin acceptor sites differ in their affinity and capacity (number of binding sites per cell) for the estrogen- and antiestrogen-receptor complexes. Thus, we suggest that the differences in the physiological and physicochemical properties of estrogens and antiestrogens may be related to their differential interaction with uterine chromatin subfractions. 相似文献
2.
Shashank Hambarde Chi-Lin Tsai Raj K. Pandita Albino Bacolla Anirban Maitra Vijay Charaka Clayton R. Hunt Rakesh Kumar Oliver Limbo Remy Le Meur Walter J. Chazin Susan E. Tsutakawa Paul Russell Katharina Schlacher Tej K. Pandita John A. Tainer 《Molecular cell》2021,81(14):2989-3006.e9
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3.
To investigate the influence of vasomotor tone and vessel compliance on pulmonary segmental vascular resistance, we determined the longitudinal distribution of vascular pressures in 15 isolated blood perfused lungs of newborn lambs. We measured pulmonary arterial and left atrial pressures and by micropuncture the pressures in 20- to 80-micron-diam subpleural arterioles and venules, both before and after paralyzing the vasculature with papaverine hydrochloride. In five lungs we also determined the microvascular pressure profile during reverse perfusion. In lungs with baseline vasomotor tone, approximately 32% of the total pressure drop was in arteries, approximately 32% in microvessels, and approximately 36% in veins. With elimination of vasomotor tone, arterial and venous resistances decreased to one-fifth and one-half of base-line values, respectively, indicating that vasomotor tone contributed mainly toward arterial resistance. During reverse perfusion, the pressure drop in veins was similar to that in arteries during forward perfusion, suggesting that the compliance of arteries and veins is comparable. We conclude that vascular tone and compliance are important factors that determine the distribution of segmental vascular resistance in lungs of the newborn. 相似文献
4.
5.
Restriction fragment length polymorphisms in dairy and beef cattle at the growth hormone and prolactin loci 总被引:2,自引:0,他引:2
Two bovine populations, a Holstein-Friesian dairy stock and a synthetic (Baladi X Hereford X Simmental X Charolais) beef stock, were screened for restriction fragment length polymorphisms (RFLPs) at the growth hormone and prolactin genes. Most RFLPs at the growth hormone gene are apparently the consequence of an insertion/deletion event which was localized to a region downstream of the structural gene. The restriction map for the genomic region including the growth hormone gene was extended. Two HindIII RFLPs at the growth hormone locus, as well as several RFLPs at the prolactin gene, seemed to be the consequence of a series of point mutations. The results are discussed in terms of the possibility that minor genomic variability underlies quantitative genetic variation. 相似文献
6.
Significant differences were observed in GAG metabolism of S. digitata and one of its intermediate vectors, C. quinquefasciatus. Distribution of different components such as hyaluronic acid, heparin-sulphate, chondroitin-4-sulphate, chondroitin-6-sulphate, dermatan sulphate and heparin was comparable in both. However, there were quantitative differences; the difference was marked in the activity of enzymes of GAG metabolism in presence and absence of diethylcarbamazine (DEC) a known antifilarial drug. While the activities of beta-galactosidase and beta-N-acetyl glucosaminidase of S. digitata systems showed an inhibition of 96.5 and 92.6% respectively, in the Culex systems they showed an inhibition of 93.3% and an activation of 18% respectively. The differences clearly indicate the existence of basic differences in GAG metabolism of vector and parasite. 相似文献
7.
(TG)n uncovers a sex-specific hybridization pattern in cattle 总被引:2,自引:0,他引:2
Y Kashi F Iraqi Y Tikochinski B Ruzitsky A Nave J S Beckmann A Friedmann M Soller Y Gruenbaum 《Genomics》1990,7(1):31-36
Screening of a bovine genomic library with the human minisatellite 33.6 probe uncovered a family of clones that, when used to probe Southern blots of bovine genomic DNA digested with the restriction enzyme HaeIII or MboI, revealed sexually dimorphic, but otherwise virtually monomorphic, patterns among the larger DNA fragments to which they hybridized. Characterization of one of these clones revealed that it contains different minisatellite sequences. The sexual dimorphism hybridization pattern observed with this clone was found to be due to multiple copies of two tandemly interspersed repeats: the simple sequence (TG)n and a previously undescribed 29-bp sequence. Both repeats appear to share many genomic loci including autosomal loci. In contrast, Southern analysis of AluI- or HinfI-digested bovine DNA with the (TG)n repeat used as a probe yielded substantial polymorphism. These results show that (i) different minisatellites can be found in a cluster, (ii) both simple and more complex repeated sequences other than the simple quaternary (GATA)n repeat can be sexually dimorphic, and (iii) simple repeats can reveal substantial polymorphism. 相似文献
8.
9.
Phylogenetic distribution in the genus Mus of t-complex-specific DNA and protein markers: inferences on the origin of t-haplotypes 总被引:8,自引:0,他引:8
Delarbre C; Kashi Y; Boursot P; Beckmann JS; Kourilsky P; Bonhomme F; Gachelin G 《Molecular biology and evolution》1988,5(2):120-133
We have examined the phylogenetic distribution of two t-specific markers
among representatives of various taxa belonging to the genus Mus. The
centromeric TCP-1a marker (a testicular protein variant specific for all
t-haplotypes so far studied) has also been apparently detected in several
non-t representatives of the Mus IVA, Mus IVB, and probably M. cervicolor
species. By contrast, a t-specific restriction- fragment-length
polymorphism allele (RFLP) of the telomeric alpha- globin pseudogene DNA
marker alpha-psi-4 was found only in animals belonging to the M.
musculus-complex species either bearing genuine t- haplotypes or, like the
M. m. bactrianus specimen studied here, likely to do so. This t-specific
alpha-psi-4 RFLP allele was found to be as divergent from the RFLP alleles
of the latter, non-t, taxonomical groups as it is from Mus 4A, Mus 4B, or
M. spretus ones. These results suggest the presence of t-haplotypes and of
t-specific markers in populations other than those belonging to the M. m.
domesticus and M. m. musculus subspecies, implying a possible origin for
t-haplotypes prior to the radiation of the most recent offshoot of the Mus
genus (i.e., the spretus/domesticus divergence), some 1-3 Myr ago.
相似文献
10.
Mamoru Koketsu Lekh Raj Juneja Hiroshi Kawanami Mujo Kim Takehiko Yamamoto 《Glycoconjugate journal》1992,9(2):70-74
Egg yolk, a large proportion of the egg, was studied for the preparation ofN-acetylneuraminic acid (Neu5Ac). The delipidated hen egg yolk (DEY; 500 kg containing 0.2% w/w, Neu5Ac) was hydrolysed with HCl (pH 1.4) at 80 °C and neutralized with NaOH (pH 6.0). The mixture was filtered and electrodialysed until the conductivity was 240 µS cm–1. The filtrate was applied on a column of Dowex HCR-W2 (20–50 mesh), followed by a column of Dowex 1-X8 (200–400 mesh). The latter column was washed with water, and then eluted with a linear gradient of HCO2H (0–2m). The eluates containing Neu5Ac were concentrated using a reverse osmosis membrane and, finally, rotary evaporated at 40 °C. The residue was then lyophilized to yield 500 g Neu5Ac. The purity of Neu5Ac was >98% (TBA method). HPLC, NMR spectroscopy and TLC chromatography of the product obtained from the DEY showed that Neu5Ac was the sole derivative present in egg yolk. The DEY, a byproduct from egg processing plants, was found to be an excellent source for the large-scale preparation of Neu5Ac.Abbreviations Neu5Ac
N-acetylneuraminic acid
- Neu5Gc
N-glycolylneuraminic acid
- DEY
delipidated egg yolk
- HPLC
high performance liquid chromatography
- TLC
thin layer chromatography
- NMR
nuclear magnetic resonance
- IR
infrared spectroscopy
Presented at the 11th International Symposium on Glycoconjugates, Toronto, Canada. 相似文献