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1.
Hubert Weber 《Journal of Ornithology》1958,99(2):160-172
Zusammenfassung Im Buchenwald des Naturschutzgebietes Serrahn (Mecklenburg) achtete Verf. seit 1949 auf den Zwergschnäpper. 1956 und 1957 brüteten dort über 12 Paare.Ankunft frühestens am 9. Mai. Als Erste erscheinen vorwiegend ältere (rotkehlige) . Den ersten folgen sehr bald die ersten .Balzflug, Zeigen der Nisthöhle, Copula sowie Variationen des Neststandes werden beschrieben.Fast stets baute nur das , in einem Falle 3 Tage lang. Während der Bauzeit setzt das seine Singflüge eifrig fort. Gepaarte verstummen, sobald ihr begonnen hat, fest auf dem Gelege zu brüten. Nur Junggesellen singen den ganzen Sommer über.An einem günstig gelegenen Nest wurde das Verhalten des Paares vom 4.(?) Bruttag ab bis zum Ausfliegen der Jungen (im Alter von 13 Tagen) aus einem dicht davor angebrachten Schirm genau beobachtet und aufgezeichnet. Nach dem Verlassen des Nestes suchen die Jungen unter Führung ihrer Eltern die nächste Dickung auf. Sobald sie selbständig geworden sind, beginnt die Jugendmauser, 3 Wochen danach die Wanderung ins Winterquartier. Die letzten Zwergschnäpper verschwanden meist vor Mitte September.Angaben über Gesang, Bedeutung der Rufe, Nahrung.Attrappen-Versuche am Nest ergaben, daß die Eltern genau zwischen dem (gefährlichen) Sperber und dem (ungefährlichen) Kuckuck zu unterscheiden wußten und ihnen gegenüber unterschiedliche Alarmlaute brachten. Tannenhäher und Wacholderdrossel lösten keine Abwehr-Reaktion aus. 相似文献
2.
Morvan-Dubois G Le Guellec D Garrone R Zylberberg L Bonnaud L 《Journal of molecular evolution》2003,57(5):501-514
Type I collagen in tetrapods is usually a heterotrimeric molecule composed of two 1 and one 2 chains. In some teleosts, a third chain has been identified by chromatography, suggesting that type I collagen should also exist as an 1(I)2(I)3(I) heterotrimer. We prepared, from zebrafish, three distinct cDNAs identified to be those of the collagen 1(I), 2(I), and 3(I) chains. In this study on the evolution of fibrillar collagen chains and their relationships, an exhaustive phylogenetic analysis, using vertebrate fibrillar collagen sequences, showed that each chain constitutes a monophyletic cluster. Results obtained with the newly isolated sequences of the zebrafish showed that the 3(I) chain is phylogenetically close to the 1(I) chain and support the hypothesis that the 3(I) chain arose from a duplication of the 1(I) gene. The duplication might occur during the duplication of the actinopterygian genome, soon after the divergence of actinopterygians and sarcopterygians, a hypothesis supported by the demonstration of a syntenic evolution between a set of fibrillar collagen genes and Hox clusters in mammals. An evolutionary scenario is proposed in which phylogenetic relationships of the chains of fibrillar collagens of vertebrates could be related to Hox cluster history.
Present address (Laure Bonnaud): Institut Jacques Monod, Tour 43, CNRS, Universités Paris 6 et 7, Equipe Evolution du Développement des Nématodes, 2 place Jussieu, 75005 Paris, France 相似文献
3.
Magdalena Kanabus Adrianna Nowicka Ewa Sledziewska-Gójska Piotr Jonczyk Zygmunt Ciesla 《Molecular & general genetics : MGG》1995,247(2):216-221
It has previously been suggested that inhibition of the proofreading 3-5 exonuclease activity of DNA polymerase may play an important role in generation of UV-induced mutations inEscherichia coli. Our previous work showing that overproduction of , the proofreading subunit of DNA polymerase III, counteracts the SOS mutagenic response ofE. coli seemed to be consistent with this hypothesis. To explore further the nature of the antimutagenic effect of we constructed plasmid pMK17, which encodes only two of the three highly conserved segments of — Exol and ExoII; the third segment, ExoIII, which is essential for 3–5 exonuclease activity, is deleted. We show that at 40°C, over-production of the truncated e subunit significantly delays production of M13 phage, suggesting that the protein retains its capacity to bind to DNA. On the other hand, the presence of pMK17 in atrpE65 strain growing at 40°C causes a 10-fold decrease in the frequency of UV-induced Trp+ mutations. This antimutagenic effect of the truncated s is effectively relieved by excess UmuD,C proteins. We also show that the presence of plasmid pIP21, which contains thednaQ49 allele encoding an subunit that is defective in proofreading activity, almost completely prevents generation of UV-induced mutations in thetrpE65 strain. We propose that the DNA binding ability of free , rather than its 3–5 exonuclease activity, affects processing of premutagenic UV-induced lesions, possibly by interfering with the interaction between the UmuC-UmuD-RecA complex and Pol III holoenzyme. This interaction is probably a necessary condition for translesion synthesis. 相似文献
4.
Summary Recombinant B factors were recovered from crosses of class Ixclass III B factors. Factors of class III are constituted of two loci, but intrafactor recombination occurs at a low frequency. B of class III B factors differs in its properties from B of class I, but B is identical with B of class I. The B locus has at least two alleles. 相似文献
5.
Creager AN 《Journal of the history of biology》1996,29(3):331-360
Conclusion Scientists and historians have often presumed that the divide between biochemistry and molecular biology is fundamentally epistemological.100 The historiography of molecular biology as promulgated by Max Delbrück's phage disciples similarly emphasizes inherent differences between the archaic tradition of biochemistry and the approach of phage geneticists, the ur molecular biologists. A historical analysis of the development of both disciplines at Berkeley mitigates against accepting predestined differences, and underscores the similarities between the postwar development of biochemistry and the emergence of molecular biology as a university discipline. Stanley's image of postwar biochemistry, with its focus on viruses as key experimental systems, and its preference for following macromolecular structure over metabolism pathways, traced the outline of molecular biology in 1950.Changes in the postwar political economy of research universities enabled the proliferation of disciplines such as microbiology, biochemistry, biophysics, immunology, and molecular biology in universities rather than in medical schools and agricultural colleges. These disciplines were predominantly concerned with investigating life at the subcellular level-research that during the 1930s had often entailed collaboration with physicists and chemists. The interdisciplinary efforts of the 1930s (many fostered by the Rockefeller Foundation) yielded a host of new tools and reagents that were standardized and mass-produced for laboratories after World War II. This commercial infrastructure enabled basic researchers in biochemistry and molecular biology in the 1950s and 1960s to become more independent from physics and chemistry (although they were practicing a physicochemical biology), as well as from the agricultural and medical schools that had previously housed or sponsored such research. In turn, the disciplines increasingly required their practitioners to have specialized graduate training, rather than admitting interlopers from the physical sciences.These general transitions toward greater autonomy for biochemistry and allied disciplines should not mask the important particularities of these developments on each campus. At the University of Caliornia at Berkeley, agriculture had provided, with medicine, significant sponsorship for biochemistry. The proximity of Lawrence and his cyclotrons supported the early development of Berkeley as a center for the biological uses of radioisotopes, particularly in studies of metabolism and photosynthesis. Stanley arrived to establish his department and virus institute before large-scale federal funding of biomedical research was in place, and he courted the state of California for substantial backing by promising both national prominence in the life sciences and virus research pertinent to agriculture and public health. Stanley's venture benefited significantly from the expansion of California's economy after World War II, and his mobilization against viral diseases resonated with the concerns of the Cold War, which fueled the state's rapid growth. The scientific prominence of contemporary developments at Caltech and Stanford invites the historical examination of the significance of postwar biochemistry and molecular biology within the political and cultural economy of the Golden State.In 1950, Stanley presented a persuasive picture of the power of biochemistry to refurbish life science at Berkeley while answering fundamental questions about life and infection. In the words of one Rockefeller Foundation officer,There seems little doubt in [my] mind that as a personality Stanley will be well able to dominate the other personalities on the Berkeley campus and will be able to drive his dream through to completion, which, incidentally, leaves Dr. Hubert [sic] Evans and the whole ineffective Life Sciences building in the somewhat peculiar position of being by-passed by much of the truly modern biochemistry and biophysics research that will be carried out at Berkeley. Furthermore, it seems likely that Dr. S's show will throw Dr. John Lawrence's Biophysics Department strongly in the shade both figuratively and literally, but should make the University of California pre-eminent not only in physics but in biochemistry as well.101
Stanley, Sproul, Weaver, and this officer (William Loomis) all testified to a perceptible postwar opportunity to capitalize on public support for biological research that relied on the technologies from physics and chemistry without being captive to them, and that addressed issues of medicine and agriculture without being institutionally subservient. What is striking, given the expectation by many that Stanley would be able to drive his dream through to completion, was that in fact he did not. Biochemists who had succeeded in making their expertise valued in specialized niches were resistant to giving up their affiliations to joint Stanley's liberated organization. Stanley's failure was not simply due to institutional factors: researchers as well as Rockefeller Foundation officers faulted him for his lack of scientific imagination, which made it difficult for him to gain credibility in leading the field. Moreover, many biochemists did not share Stanley's commitment to viruses as the key material for the new biochemistry.In the end, Stanley's free-standing department did become a first-rate department of biochemistry, but only after freeing itself from Stanley's leadership and his single-minded devotion to viruses. Nonetheless, the falling-out with the Berkeley biochemists was rapidly followed by the establishment of a Department of Molecular Biology, attesting to the unabating economic and institutional possibilities for an authoritative general biology (or two, for that matter) to take hold. In each case, following Stanley's dream sheds light on how the possible and the real shaped the (re)formation of biochemistry and molecular biology as postwar life sciences. 相似文献
6.
V. Hyne M. J. Kearsey O. Martìnez W. Gang J. W. Snape 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(6):735-741
F1 plants between two intervarietal chromosome substitution lines of European spring wheat varieties, Sicco (Chinese Spring 5B) and Highbury (Chinese Spring 5B), were used to produce 114 doubled haploid lines, 45 by the Hordeum bulbosum technique and 69 by anther culture. These two sets of lines were characterized for variation at a range of morphological, isozyme and RFLP marker loci, and genetic maps were developed with emphasis on chromosomes 6B, 7A, 7B and 7D. A subset of lines, scored for production traits in field trials in 1986 and 1987, were analysed for quantitative trait loci (QTL). The performance of the lines for the quantitative traits studied showed no overall differences due to the method of production of the lines. QTL were located on the linkage map for ear emergence time, height, tiller weight, yield and 50-grain weight using four analytical methods. Many of these effects showed genotype x year interaction. 相似文献
7.
Titin/connectin is a giant muscle protein with a highly modular architecture consisting ofmultiple repeats of two sequence motifs, named type I and type II. Type I modules have beensuggested to be intracellular members of the fibronectin type III (Fn3) domain family. Alongthe titin sequence they are exclusively present in the region of the molecule located in thesarcomere A-band. This region has been shown to interact with myosin and C-protein. Oneof the most noticeable features of type I modules is that they are particularly rich insemiconserved prolines, since these residues account for about 8% of their sequence. We havedetermined the secondary structure of a representative type I domain (A71) by 15N and 1HNMR. We show that the type I domains of titin have the Fn3 fold as proposed, consisting ofa three- and a four-stranded -sheet. When the two sheets are placed on top of each other toform the -sandwich characteristic of the Fn3 fold, 8 out of 10 prolines are found on the sameside of the molecule and form an exposed hydrophobic patch. This suggests that thesemiconserved prolines might be relevant for the function of type I modules, providing asurface for binding to other A-band proteins. The secondary structure of A71 was structurallyaligned to other extracellular Fn3 modules of known 3D structure. The alignment shows thattitin type I modules have closest similarity to the first Fn3 domain of Drosophila neuroglian. 相似文献
8.
Dietrich Trincker 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1954,36(2):135-146
Zusammenfassung Die vorliegende Arbeit ist die 2. einer Reihe, deren Ziel die vergleichend-physiologische Untersuchung der Dynamik zentralnervöser Selbststeuerungssysteme sein soll. Die bei Anpassungsvorgängen auftretenden Änderungen des motorischen Verhaltens der Lebewesen werden als Schwingungsvorgänge im mathematischen Sinne aufgefaßt. Die Güte der Anpassung wird definiert als die zu der Einschwingungskurve gehörige Fläche.Ebenso wie die in der I. Mitteilung untersuchten Axolotl (Amblystoma) zeigen auch die hier benutzten Tische (Carassius carassius) periodisch gedämpften Einschwingungstyp. Dieser scheint bei niederen Wirbeltieren häufig zu sein (verbunden mit relativ großer Fläche, d. h. geringer Güte), während bei höheren Wirbeltieren, besonders beim Menschen, aperiodische Einschwingung (mit nahezu minimaler Fläche, also optimaler Güte) vorherrscht.Die Versuche bezogen sich hier nicht (wie bei der I. Mitteilung) auf die Anpassungsleistung von Einzeltieren, sondern auf die Verhaltensänderung eines Kollektivs. Da es sich bei diesen Fischen um ausgesprochene Schwarm-Tiere handelt, erschien dieser Weg als der biologisch richtigere. 相似文献
9.
Synposis The periodic acid oxidation of the glycogens in sections of ox liver fixed in Carnoy's fluid has been studied quantitatively. It was found that in 0.02 M acetate buffer at pH 5.0 the oxidation was rapid at first but levelled off after I hr. Even after prolonged oxidation (12 days), not more than 23–24% of the total available glycogen was oxidized. However, in the presence of electrolytes (e.g. 0.2.m sodium chloride) the oxidation was much greater. After 2.5 hr, for example, 40% of the available glycogen was oxidized. There was little difference in the velocity of oxidation in sections mounted on glass-slides and free-floating ones, or in free-floating sections of different thicknesses.Mounted and unmounted sections consumed on average 11–17 times more periodate than could be accounted for by the oxidation of their glycogen content.The results are interpreted in terms of a complex formed between periodate ions and the cuter glucosyl residues of the glycogen aggregate. The negative charge on the complex, it is suggested, prevents free periodate ions approaching and oxidizing the inner glycosyl residues. 相似文献
10.
B. Bengtsson 《Plant Ecology》1992,101(1):35-41
Beech seedlings (Fagus sylvatica L. provenance Västra Torup) were grown in nutrient solution at low pH (4.2) and exposed to AlCl3 and different concentrations of nitrogen. The effects of AlCl3 and nitrogen on uptake of Ca2+ (45Ca) and H2PO4
- (32P) in roots of intact beech were studied. Crossections of roots were analyzed with respect to element concentrations, by use of Mikro-PIXE (particle induced X-ray emission). The distribution of Al, Ca, P, Mg, K, and S was analysed. The experiments were designed to evaluate the effects of aluminium on localization of elements in plant root tissue.Aluminium reduced the concentration of Ca in plants and increased that of K. High nitrogen levels in the solution further decreased the concentration of Ca in the roots. Aluminium (1.0 mM) effectively reduced the Ca2+ (45Ca) uptake in short time experiments. Aluminium accumulated in high concentration (up to 500 mol/g dry weight in areas of 30×30 m2) on the root surface, epidermis and outer layers of cortex. Corresponding areas had an extremely low Ca concentration (ca 5 mol/g dry weight) which could be harmful for regulation of mineral uptake and development of roots.It is concluded that the calcium concentration in roots was reduced by aluminium. The combination with high nitrogen levels further reduced calcium changing the mineral balance which could result in deficiency conditions of calcium in the root. 相似文献
11.
Panagakos Fotinos S. Fernandez Cesar Kumar Suriender 《Molecular and cellular biochemistry》1996,159(1):81-84
The study, addressed to understand whether or not human platelets possess a unique thiol-oxidase whose activity could be modulated by signalling pathway initiated upon the activation of Receptor-Ck revealed the existence of disulphide-dependent oxidation within these cells and this phenomenon was regulated by Receptor-Ck-dependent generation of second messengers especially phosphatidic acid (PA); cAMP and cGMP. Purification of this activity revealed the existence of 47 kDa protein having thiol-oxidase activity. Keeping in view these results we propose that the existence of this novel 47 kDa Thiol-oxidase within human platelets may provide a crucial switch for the regulation of Receptor-Ck-dependent mevalonate pathway in human platelets. 相似文献
12.
David R. Wolstenholme 《Chromosoma》1971,33(4):396-402
DNA molecules from lysates of microsporocytes at different stages of meiosis of Lilium longiflorum were examined in the electron microscope. In all of the preparations, only linear (non-circular) molecules were found. They had a mean length of between 59 and 75 , and a range of lengths which varied from 1 to 115 , to 1 to 210 . From the data obtained, there was no indication of a change in molecular form or size of DNA molecules associated with the process of meiosis. 相似文献
13.
The antigenic relationships between the prolamins of barley, rye and wheat have been studied by examining the specificity of an antibody to C hordein in a quantitative study using a laser nephelometer. The antibody reacts weakly with B hordein and strongly with 75-kdalton and 40-kdalton -secalins from rye and 3 some -gliadins from wheat. Absorption experiments and immunodiffusion tests indicate that there are shared antigenic determinants for most of the prolamins. All the species with reacting prolamins belong to the sub-family Festucoideae of the Gramineae. The prolamins of maize, pearl millet and sorghum, species of the sub-family Panicoideae, do not react. The results confirm the known lack of homology between the prolamins of the two sub-families and also indicate the presence of relationships not yet established between C hordein, the 75-kdalton and 40-kdalton -secalins and also 3 gliadin.Abbreviations HMW
high molecular weight
- PAGE
polyacnylamide-gel electrophoresis
- PBS
phosphate-buffered saline
- RLS
relative light scattering
- SDS
sodlum dodecyl sulphate 相似文献
14.
According to their respective elution order, specificity for cAMP and cGMP, their sensitivity to calmodulin, and their modulation by cGMP and rolipram, four cyclic nucleotide phosphodiesterases (PDE) were separated from the cytosol: PDE I (calmodulin-sensitive), PDE II (stimulated by cGMP, PDE IV (cGMP specific-PDE and inhibited by rolipram) and PDE V (cGMP specific). PDE IV (Km=1.4 M) was competitively inhibited rolipram (Ki=1.2 M) whereas PDE V (Km=0.83 M) was competitively inhibited by zaprinast in the molar range (Ki=0.12 M). Moreover the microsomal fraction contained three PDE isoforms: PDE II, PDE III (inhibited by cGMP or indolidan) and PDE IV. These results show that cAMP degradation in cytosolic and membrane fractions is modulated by cGMP and selectively inhibited by rolipram and, in addition, by indolidan in membrane fractions. (Mol Cell Biochem140: 171–175, 1994) 相似文献
15.
Mass spectrometric analysis of genetic and post-translational heterogeneity in the lectins Jacalin andMaclura pomifera agglutinin 总被引:1,自引:0,他引:1
Jacalin andM. pomifera agglutinin are T-antigen specific lectins with 44 structures that show far greater microheterogeneity than plant lectins from other families, due to multiple genetic isoforms and post-translational processing. Electrospray mass spectrometry and combined liquid chromatography-electrospray mass spectrometry were used to characterize the various forms. For both lectins, the mass data were consistent with previous protein sequencing of the major -chain species of 133 residues and three -chain species of 20 or 21 residues. In addition, for jacalin the mass of one minor -chain species was consistent with a second of the four reported gene sequences. However, the glycopeptide -chain form and one -chain form did not match any of the genes, suggesting a fifth gene remains to be found. ForM. pomifera agglutinin, three more -chain forms were found, but all six could arise from only two genes, with additional post-translational proteolysis and post-translational substitution with an unidentified component of 106 Da creating the set of six forms. Only two -chain forms were found also, with no glycosylation. 相似文献
16.
The fine order of genes in the class III region of the swine major histocompatibility complex (MHC), the SLA complex, was examined by pulsed field gel electrophoresis (PFGE) and Southern blot analysis. Four genes, C2, HSP70, TNF, and CYP21, were analyzed. The CYP21, C2, and HSP70 genes were all located within a 200-kb NotI fragment. The C2, HSP70, and TNF genes cohybridized to a 420-kb SalI fragment. The TNF gene is linked to the class I region by a 390-kb NotI fragment. Combined with a previous study from our lab, the order of genes in the SLA complex is class II-class III [(CYP21/C4)-(Bf/C2/HSP70)-TNF]-class I. The size of the class III region from CYP21 to TNF is estimated to be 500 kb. This size and the order of the genes in the swine class III region are similar to those of human, mouse, goat, and rabbit, which confirms the high conservation of class III gene organization across species. 相似文献
17.
L. A. Kuznetsova S. A. Plesneva 《Journal of Evolutionary Biochemistry and Physiology》2001,37(5):520-527
The effects of biogenic amines, glucagon, and insulin on the cAMP-dependent protein kinase A (PKA) activity have been studied in the muscle tissue of the freshwater bivalve mollusc Anodonta cygnea. It was shown that serotonin, glucagon, and insulin both in vivo and in vitro stimulated PKA activity, whereas isoproterenol inhibited it. The stimulating effect of serotonin and inhibiting effect of isoproterenol was blocked by serotoninergic (cyproheptadine) and adrenergic (propranolol) inhibitors, which confirms specificity of the effect of biogenic amines on the PKA activity. Taking into account participation of adenylyl cyclase system in action of the above hormones, the revealed hormonal effects on the PKA activity produce metabolic effects via the following chain reaction. In the case of serotonin and glucagon: receptor Gs-protein AC cAMP PKA phosphorylation of glycogen synthase (GS) and glucose-6-phosphate dehydrogenase (G6PDH) and inhibition of their activity; in the case of isoproterenol: -adrenoreceptor Gi-protein AC inhibition decreasing PKA inhibition of phosphorylase and stimulation of GSI and G6PDH. A participation is suggested of the insulin-stimulated AC signaling system in the mechanism of the mitogenic insulin effect mediated, as shown in this work, via the PKA activation, but not of the metabolic effect of insulin. 相似文献
18.
Gaume V Figard H Mougin F Guilland JC Alberto JM Gueant JL Alber D Demougeot C Berthelot A 《Amino acids》2005,28(3):337-342
Summary. The purpose of this study was to investigate the effects of a 8-week of swim training on total plasma homocysteine and cysteine levels in 16 male Sprague-Dawley rats aged 17 weeks. We also evaluated the activity of hepatic cystathionine -synthase (CBS), an enzyme involved in the metabolism of Hcy, the concentration of plasma glutathione, taurine, and a fraction of vitamin B6: the pyridoxal 5-phosphate (PLP). After one week of acclimatization, rats were randomly divided into two groups: 8 non-trained (NTR) and 8 trained rats (TR). Following the training period, body weight gain was lower in TR than in NTR. Plasma homocysteine did not differ among groups while significantly lower plasma cysteine and taurine levels were found in TR (157.83±8.6mol/L; 133.01±9.32mol/L; P<0.05) compared with data of NTR (176.19±4.9mol/L; 162.57±8.16mol/L; P<0.05). No significant changes in hepatic CBS activity were observed in TR compared with NTR. Moreover, values for plasma glutathione and PLP concentrations were not affected by training.These results indicate that training reduces plasma cysteine and taurine levels whereas it does not modify other studied parameters. Thus, physical training may regulate cysteine metabolism. 相似文献
19.
Luciano Gastaldo Romeo Ciabatti Francesco Assi Ermenegildo Restelli Jurgen K. Kettenring Luigi F. Zerilli Gabriella Romanò Maurizio Denaro Bruno Cavalleri 《Journal of industrial microbiology & biotechnology》1992,11(1):13-18
Summary WhenActinoplanes strain ATCC 33076, the producer of A-16686 A1, A2 and A3 complex, is fermented in a suitable medium three additional factors, designated A1, A2 and A3 are produced. These were isolated and characterized, and were shown to differ from the parent components of the original complex by lacking one mannose unit. Bioconversion of A factors into A factors was achieved by incubation with the mycelium ofActinoplanes ATCC 33076. Factor A2 has better antibacterial activity than A2 against some bacteria. 相似文献
20.
Segarini PR 《Cytotechnology》1989,2(4):307-316
Transforming growth factor beta (TGF-) binds specifically and with high affinity to several different cell surface proteins. Low Mr proteins of 50,000 and 80,000 have been termed type I and type II receptors. Intermediate sized binding components of 115,000–140,000 Mr and a high binding components of approximately 250,000 Mr in subunit size have been termed type III receptors. The high Mr component is a proteoglycan containing the glycosaminoglycan chains of heparan sulfate and chondroitin sulfate and the intermediate sized components are its core proteins. Although almost all cells have TGF- receptors, binding of TGF- to the type III binding components is restricted to cells of fibroblastic, osteoblastic and chondroblastic origin. The physiological relevance of each individual binding class is unclear. However, recent data indicate that the type III protein does not transmit signals to inhibit cell proliferation, induce protein synthesis, or promote cytomorphological change and that these activities may be mediated through the type I receptor. The mechanism of signal transduction remains unknown, but it does not appear to be associated with tyrosine phosphorylation or phosphorylation of the 40s ribosomal protein S6.Abbreviations TGF
Transforming Growth Factor
- GAG
Glycosaminoglycan
- EGF
Epidermal Growth Factor 相似文献