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Many studies have established a correlation of differences in the activities of various muscle types with differences in the expression of myosin isoforms. In this paper we report the sequence determination of myosin light chain-2 from rabbit slow skeletal (LC2s) and ventricular (LC2v) nmscles. We sequenced tryptic peptides from LC2v which account for all except a few terminal amino acid residues. The major part (87 residues) of the rabbit LC2s sequence, obtained from tryptic and cyanogen bromide (CNBr) peptides, was found to be identical to rabbit LC2v. Our results provide the first sequence information on LC2s from any species, and lend strong support to the hypothesis that LC2s and LC2v are identical. Comparisons of rabbit LC2v and LC2s with rabbit LC2f (from fast skeletal muscle), and also with chicken LC2f and LC2v, show clearly that LC2s and LC2v from mammalian and avian species are more closely related to each other than they are to LC2f isoforms from the same species. 相似文献
3.
Sandra Afione Luciano Debeljuk Adriana Seilicovich Daniel Pisera Mercedes Lasaga María del Carmen Díaz Beatriz Duvilanski 《Peptides》1990,11(6):1065-1068
In the present work we examined the effect of the neutralization of endogenous substance P by the administration of an anti-substance P serum (ASPS) on GABA concentration in the anterior pituitary in hyperprolactinemic conditions induced by 5-hydroxytryptophan or by grafting anterior pituitaries. ASPS reduced the increase in the anterior pituitary GABA concentration induced by hyperprolactinemia. In vitro experiments showed that substance P inhibited K+-evoked GABA efflux from hypothalamic fragments and decreased GABA concentration in the anterior pituitary but ASPS increased it. Our results demonstrate that substance P modifies hypothalamic GABA release and anterior pituitary GABA concentration and suggest that an interaction exists between substance P and GABA. 相似文献
4.
Jose Pontón Fernando L. Hernando Maria Dolores Moragues Pedro L. Barea Mara Gerloni Stefania Conti Paola Fisicaro Cristina Cantelli Luciano Polonelli 《Mycopathologia》1996,133(2):89-94
The presence of heat shock mannoproteins (HSMPs) reactive with sIgA was demonstrated in several C. albicans strains. The subculture of the C. albicans isolated from mucosal surfaces on Sabouraud's dextrose agar at 25 °C switched off the HSMP expression. A re-expression of the HSMPs was obtained in the same medium by shifting the temperature of incubation to 37 °C. However, expression of HSMPs in two strains isolated from deep infections was maintained during several subcultures on Sabouraud's dextrose agar at 25 °C. A glycoprotein of 200 kDa seemed to be the main HSMP reacting with vaginal sIgA. The data presented in this study suggest that factors other than temperature can influence the expression of C. albicans HSMPs and therefore these antigens should be referred as stress mannoproteins.Abbreviations HSMPs
heat shock mannoproteins
- MAb
monoclonal antibody
- sIgA
secretory IgA 相似文献
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Karri Silventoinen Sampo Sammalisto Markus Perola Dorret I Boomsma Belinda K Cornes Chayna Davis Leo Dunkel Marlies De Lange Jennifer R Harris Jacob V B Hjelmborg Michelle Luciano Nicholas G Martin Jakob Mortensen Lorenza Nisticò Nancy L Pedersen Axel Skytthe Tim D Spector Maria Antonietta Stazi Gonneke Willemsen Jaakko Kaprio 《Twin research》2003,6(5):399-408
A major component of variation in body height is due to genetic differences, but environmental factors have a substantial contributory effect. In this study we aimed to analyse whether the genetic architecture of body height varies between affluent western societies. We analysed twin data from eight countries comprising 30,111 complete twin pairs by using the univariate genetic model of the Mx statistical package. Body height and zygosity were self-reported in seven populations and measured directly in one population. We found that there was substantial variation in mean body height between countries; body height was least in Italy (177 cm in men and 163 cm in women) and greatest in the Netherlands (184 cm and 171 cm, respectively). In men there was no corresponding variation in heritability of body height, heritability estimates ranging from 0.87 to 0.93 in populations under an additive genes/unique environment (AE) model. Among women the heritability estimates were generally lower than among men with greater variation between countries, ranging from 0.68 to 0.84 when an additive genes/shared environment/unique environment (ACE) model was used. In four populations where an AE model fit equally well or better, heritability ranged from 0.89 to 0.93. This difference between the sexes was mainly due to the effect of the shared environmental component of variance, which appears to be more important among women than among men in our study populations. Our results indicate that, in general, there are only minor differences in the genetic architecture of height between affluent Caucasian populations, especially among men. 相似文献
7.
The penetration of bovine kidney cells by infectious bovine rhinotracheitis virus, a member of the herpesvirus group, was
investigated using the direct immunoferritin labeling technique. Electron microscopic examination of infected cells after
10 min at 37°C revealed fusion between viral envelope and cell membrane; the former reacted with the ferritin particles conjugated
with antiviral antibody. However, shortly after penetration of the nucleocapsid, viral-specific antigenic sites on the plasma
membrane were not detected by the immunoferritin technique. Antigenically reactive structures in a disorganized array were
frequently detected extracellularly, situated above the penetration sites as indicated by the internalized nucleocapsids. 相似文献
8.
Summary The growth of two strains of the petitenegative yeast Kluyveromyces lactis is inhibited by Tetracycline in different ways under the same culture conditions. Tetracycline resistant mutants of one strain have been isolated which can tolerate doses as high as 3000 g/ml of antibiotic.The segregation pattern of this character obtained by random spore analysis of the ascospores derived from the cross of the two strains strongly suggests that the resistance to tetracycline is under mitochondrial control. 相似文献
9.
Dr. Laura Curatolo Christine Chaponnier Maria Benedetta Donati Luciano Morasca Giulio Gabbiani 《Cell and tissue research》1982,223(3):665-673
Summary It is known that human and animal fibroblasts are able to induce the retraction of a fibrin clot. In the present study the correlation between (i) fibrinclot retractile (FCR) activity, (ii) the number of actin stress-lines in mouse fibroblasts during growth in culture, and (iii) the sensitivity of actin stress-lines to a powerful actin-depolymerizing factor (ADF), present in plasma and serum of humans and laboratory animals was investigated. Fibroblasts at early passages (2–4) were tested for these parameters at various intervals after seeding (24, 96, and 168 h). The number of actin stress-lines was progressively higher, while the sensitivity to ADF action was progressively lower in cells cultured from 24 to 168 h; the FCR capacity was significantly decreased at 168 h. These data suggest that cells containing weakly polymerized and/or stabilized actin are more active than those containing highly polymerized and/or stabilized actin in triggering fibroblast contraction. 相似文献
10.