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1.
In recent years, the enzyme Ca2+/calmodulin-stimulated protein kinase II1 (CaM-PK II) as attracted a great deal of interest. CaM-PK II is the most abundant calmodulin-stimulated protein kinase in brain, where it is particularly enriched in neurons (Ouimet et al., 1984; Erondu and Kennedy, 1985; Lin et al., 1987; Scholz et al., 1988). Neuronal CaM-PK II has been suggested to be involved in several phenomena associated with synaptic plasticity (Lisman and Goldring, 1988; Kelly, 1992), including long-term potentiation (Malinow et al., 1988; Malenka et al.,1989), neurotransmission (Nichols et al., 1990; Siekevitz, 1991), and learning (for review, see Rostas, 1991). This enzyme has also been postulated to be selectively vulnerable in several pathological condition, including epilepsy/kindling (Bronstein et al.,1990; Wu et al., 1990), cerebral ischemia (Taft et al., 1988), and organophosphorus toxicity (Abou-Donia and Lapadula, 1990).  相似文献   

2.
The S6 kinase signaling pathway in the control of development and growth   总被引:15,自引:0,他引:15  
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3.
Nonhistone protein BA has been shown to decrease in amount in the chromatin of growth- stimulated normal rat liver (Yeoman et al. 1975. Cancer Res. 35:1249-1255) and in mitogen-stimulated normal human lymphocytes (Yeoman et al. 1976. Exp. Cell Res. 100:47- 55.). Subsequently, protein BA was purified and was shown to prefer to bind to double- stranded A-T-rich DNAs (Catino et al. 1978. Biochemistry. 17:983-987.). Immunization of rabbits with highly purified protein BA has resulted in the production of a specific antibody. A specific immunoreactivity for chromosomal protein BA has been demonstrated by immunoelectrophoresis and double antibody immunoprecipitation analysis with rabbit anti-BA immunoglobulin and IgG fractions. Light microscope examination of normal rat liver crysections by the indirect immunofluorescence procedure has demonstrated a cytoplasmic as well as a nuclear localization for protein BA with a pronounced perinucleolar fluorescence. Immunoelectron microscopy employing the peroxidase antiperoxidase method of antigen localization has confirmed the immunofluorescence data and has show a heterochromatin localization for protein BA. The relationship of the localization of protein BA to gene control in quiescent cells or to configurations of heterochromatin as well as the marked reduction in the amounts of protein BA which occur in stimulated growth states remains to be defined.  相似文献   

4.
5.
MOTIVATION: The PFDB (Protein Family Database) is a new database designed to integrate protein family-related data with relevant functional and genomic data. It currently manages biological data for three projects-the CATH protein domain database (Orengo et al., 1997; Pearl et al., 2001), the VIDA virus domains database (Albà et al., 2001) and the Gene3D database (Buchan et al., 2001). The PFDB has been designed to accommodate protein families identified by a variety of sequence based or structure based protocols and provides a generic resource for biological research by enabling mapping between different protein families and diverse biochemical and genetic data, including complete genomes. RESULTS: A characteristic feature of the PFDB is that it has a number of meta-level entities (for example aggregation, collection and inclusion) represented as base tables in the final design. The explicit representation of relationships at the meta-level has a number of advantages, including flexibility-both in terms of the range of queries that can be formulated and the ability to integrate new biological entities within the existing design. A potential drawback with this approach-poor performance caused by the number of joins across meta-level tables-is avoided by implementing the PFDB with materialized views using the mature relational database technology of Oracle 8i. The resultant database is both fast and flexible. This paper presents the principles on which the database has been designed and implemented, and describes the current status of the database and query facilities supported.  相似文献   

6.
<正>Dear Editor,As a major protein of cypovirus capsid shell,VP5 performs as the clamp protein to stabilize the capsid shell structure(Yu et al.,2008).And as a part of viral RNA(vRNA)replication machinery,VP5 has been found to possess an ATP-independent RNA chaperoning activity(Yang et al.,2014).Here,we report that VP5 also has the  相似文献   

7.
An almost complete cDNA copy of human growth hormone has been cloned and sequenced. The nucleotide sequence confirms the known protein sequence and predicts the sequence of a precursor region of 26 amino acids. We have compared the nucleotide sequence to that for the homolgous proteins, rat growth hormone and human chorionic somatomammotropin (Seeburg et al. and Shine et al., Nature 270, 486 (1977)). There appears to be evolutionary conservation of mRNA sequence features not related to protein structure.  相似文献   

8.
RIP3 finds partners in crime   总被引:1,自引:0,他引:1  
Chan FK  Baehrecke EH 《Cell》2012,148(1-2):17-18
Programmed necrosis has long been recognized as a crucial component of animal development; however, the signaling pathway beyond the protein kinases RIP1 and RIP3 remains largely unknown. Sun et?al. and Wang et?al. now identify critical factors downstream of RIP1 and RIP3 in programmed necrosis, extending our understanding of this form of cell death.  相似文献   

9.
Folin and Ciocalteu's phenol reagent may be reduced by a variety of compounds, which therefore interfere with the Lowry method of protein determination (1,2). Peters and Fouts (3) reported that two of the zwitterionic biological buffers described by Good et al. (4) reacted strongly with the Folin reagent and thus seriously interfered with protein determinations. The zwitterionic buffers have many properties which lead to their use in biological work, where protein estimations will be required. Since the publication of Good et al. (4), the range of zwitterionic buffers has been increased. The possibility that these other buffers may also produce artefacts has therefore been investigated.  相似文献   

10.
11.
In the last few years special interest has been focused on enteric diseases localized to the lower alimentary tract, especially the ileum of weaned pigs. An increasing frequency of disorders of unknown aetiology described as regional ileitis (Emsbo 1951), necrotic enteritis (Jubb & Kennedy 1970), and intestinal adenomatosis (Rowland et al. 1973) has been reported. The changes include thickening of the ileal mucosa with hypertrophy of the muscular wall. The normal structure of villi is replaced by a proliferation of crypt cells. Necrosis of the mucosa and granulation-tissue proliferation in the submucosa occur in later stages. Regional ileitis in man (Crohn et al. 1932) which is described as a chronic enteric disease with granulomatous inflammatory changes localized to segments of the ileum is also attracting increasing attention in medical research (Liljefors 1972). The lesions are also found in the colon, and the presence of a transmissible agent involved in the aetiology of Crohn's disease has been discussed on the basis of animal experiments (Cave et al. 1973). The disease in pigs is accompanied by haematological changes, including decreased concentration of total serum protein, albumin, alkaline phosphatase, and zinc (Martinsson et al. 1974, 1976).  相似文献   

12.
The existence of a fifth essential protein for pantothenate biosynthesis in some enteric bacteria has recently been reported by Stuecker et al. [10] and Nozaki et al. (in press) [9]. This protein, PanZ, catalyses the activation of the PanD zymogen to form ADC and is essential for prototrophic growth. In this paper, we characterise the interaction of PanZ with coenzyme A and a constitutively inactive mutant of PanD using a combination of isothermal titration calorimetry and mass spectrometry. These approaches reveal that the two proteins interact with nanomolar affinity in a CoA-dependent fashion to form a heterooctameric complex.  相似文献   

13.
JAK2 is a cytoplasmic tyrosine kinase whose gene is located on chromosome 9p24. It is involved in the regulation of different cytokines and growth factors and plays an important role in the diagnosis and treatment of myeloproliferative neoplasms (Smith et al., 2008). Translocations involving the JAK2 locus are uncommon with just a few cases described in the literature, and they usually lead to a fusion protein with JAK2 (Patnaik et al., 2010). Chromosome 9p24 abnormalities have been described in myeloid and lymphoid neoplasms including chronic myelogenous leukemia (CML), acute megakaryoblastic leukemia, CD10+ B-cell acute lymphoblastic leukemia, T-cell ALL and chronic myeloproliferative disorders (CMD) (Smith et al., 2008; Lacronique et al., 1997). Although the breakpoints of each translocation are known, characterization of the partner gene has not been done in many of the cases reported due to insufficient sample or other factors. In the present study we review all translocations involving JAK2 that have been reported in the literature.  相似文献   

14.
The Hedgehog (HH) signaling pathway is a central regulator of embryonic development, controlling the pattern and proliferation of a wide variety of organs. Previous studies have implicated the secreted protein, Scube2, in HH signal transduction in the zebrafish embryo (Hollway et al., 2006; Kawakami et al., 2005; Woods and Talbot, 2005) although the nature of the molecular function of Scube2 in this process has remained undefined. This analysis has been compounded by the fact that removal of Scube2 activity in the zebrafish embryo leads to only subtle defects in HH signal transduction in vivo (Barresi et al., 2000; Hollway et al., 2006; Ochi and Westerfield, 2007; van Eeden et al., 1996; Wolff et al., 2003). Here we present the discovery of two additional scube genes in zebrafish, scube1 and scube3, and demonstrate their roles in facilitating HH signal transduction. Knocking down the function of all three scube genes simultaneously phenocopies a complete loss of HH signal transduction in the embryo, revealing that Scube signaling is essential for HH signal transduction in vivo. We further define the molecular role of scube2 in HH signaling.  相似文献   

15.
Microinjection of antipain, an inhibitor of thiol and Ca2+-dependent proteases, in immature Xenopus oocytes inhibited meiotic maturation induced by progesterone, but not by transfer of cytoplasm taken from maturing oocytes. Oocytes could be released from antipain inhibition by increasing progesterone concentration. alpha-32P-ATP was microinjected to study adenylcyclase in ovo. As already reported, neosynthesis of cAMP was decreased following progesterone application. This decrease was not observed, or it was considerably reduced, in oocytes previously injected with antipain. In amphibian, full-grown ovarian oocytes are arrested at first meiotic prophase, and have a large nucleus known as the germinal vesicle. Progesterone induces the production of a cytoplasmic maturation-promoting factor (MPF), which itself triggers germinal vesicle breakdown (GVBD), and subsequent events of meiotic maturation (Masui and Markert, 1971; Gerhart et al., 1984). A considerable body of evidences support the view that release from prophase block is due to inactivation of a cAMP-dependent protein kinase (reviewed by Maller, 1983). On the other hand, progesterone has been shown to induce a transient decrease in cAMP level (Speaker and Butcher, 1977; Schorderet-Slatkine et al., 1982; Cicirelli et al., 1985), and this initial drop of cAMP, along with a number of studies indicating a decrease in adenylate cyclase activity (Mulner et al., 1979; Baltus et al., 1981; Sadler and Maller, 1981; Finidori-Lepicard et al., 1981; Jordana et al., 1981), provided key support to the theory that an early drop in cAMP led to the dephosphorylation of a hypothetical protein which initiates maturation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
Escherichia coli haemolysin (Hlya) is a pore-forming protein which belongs to the family of 'Repeat-toxins' (RTX) (Lo et al., 1987; Lally et al., 1989; Kraig et al., 1990). A model for the pore-forming structure of HlyA has been proposed (Ludwig et al., 1991) which consists of eight transmembrane segments all present in this hydrophobic region of HlyA. We report here that two synthetic peptides of 10 and 8 amino acids in length (Pep1 and Pep2, respectively), which are derived from transmembrane segment V, are able to form pores in an artificial lipid bilayer. In addition, Pep1 exhibits strong haemolytic activity when tested on human red blood cells (HRBCs). The haemolytic activity of Pep1 and of E. coli haemolysin is completely inhibited by antibodies raised against Pep1.  相似文献   

17.
Blaner WS 《Cell metabolism》2007,5(3):164-166
How retinol (vitamin A) is taken up by cells has been an area of active research since the first report of a cell-surface receptor for retinol-binding protein (RBP) in the mid-1970s. Two recent reports, by Kawaguchi et al. (2007) and Pasutto et al. (2007), provide compelling data regarding the molecular identity and properties of a RBP receptor and open new research avenues for a better understanding of retinoid biology.  相似文献   

18.
Summary Pieces of coverslip glass coated with various proteins were implanted under one edge of a fresh skin wound on adult newt hind limbs so that the implant served as wound bed for the migrating wound epithelium. Laminin, a protein that has been implicated as an epithelial-specific adhesin, was a moderately good migration substrate. Type-IV collagen, fibrinogen and fibronectin, however, were significantly better. Fetuin, myoglobin, and casein all proved to be very poor substrates, allowing practically no migration. The inability of fetuin, myoglobin, and casein to support migration is further evidence that the considerable migration that occurs on collagen (Donaldson et al. 1982) fibrinogen and fibronectin (Donaldson and Mahan 1983) and the moderate migration on laminin, is a relatively specific response to these proteins and is therefore of special significance. The fact that laminin is a poorer migration substrate than collagen, fibrinogen or fibronectin suggests that the absence of cell surface laminin that has been associated with epithelial movement in several studies (Stanley et al. 1981; Clark et al. 1982; Madri and Stenn 1982; Gulati et al. 1983) may promote motility by allowing epithelial cells to interact directly with other extracellular macromolecules.  相似文献   

19.
The tricarboxylate carrier has recently been purified from rat liver mitochondria by three distinct scientific groups using different methods. A 37–38-kDa protein has been prepared by silca gel 60 chromatography by our group (Claeys and Azzi, 1989; Glerumet al., 1990). The specific citrate transport activity of this preparation is not significantly different from that measured in mitochondria and it is inhibitable by 1,2,3-benzenetricarboxylic acid. Bisacciaet al. (1990) have reported the isolation of a 30-kDa protein by Celite 535 chromatography, and Kaplan's group (Kaplanet al., 1990) have isolated a 32.5-kDa protein by Matrex Orange, Matrex Blue, and Affi-Gel chromatography. Peptide mapping has failed to support any structural homologies between the 37–38-kDa and the 30–32.5-kD proteins. The 38-kD protein is N-terminally blocked. The peptides obtained by several cleavage procedures have been partially sequenced. Their sequence information has been used to obtain different cDNA clones by a dual approach, the polymerase chain reaction and screening of a ZAP cDNA library. The largest cDNA which could be isolated is 2,986 bp in length and contains a 1071-bp-long open reading frame and an unusually long 3 untranslated region, both of which have been completely sequenced. The protein sequence of the carrier from the first in-frame methionine is 322 amino acids in length and exhibits a molecular mass of 35,546. Comparison of the protein sequence to the sequences of the four members of the mitochondrial carrier protein family (ADP/ATP carrier, phosphate carrier, 2-oxoglutarate/malate carrier, and uncoupling protein) does not reveal significant similarity (cf. Walkeret al., 1987). A tripartite internal homology, which is a characteristic of these proteins, is not present in the sequence of the tricarboxylate carrier protein. The mRNA for the tricarboxylate carrier is expressed in rat liver and brain, but not in rat heart.  相似文献   

20.
《The New phytologist》1999,142(3):589-591
In the November 1998 issue of New Phytologist , we published the Tansley review 'Gibberellins: regulating genes and germination' by Sian Ritchie and Simon Gilroy ( New Phytol. (1998) 140 , 363–383). Since its publication, it has come to our attention that text associated with Fig. 4 was omitted during production. The correct figure is reprinted here in full.
We apologise to the author and to our readers for this mistake.
Figure 4. Promoter sequences of various genes expressed in the cereal aleurone and shown to be regulated by GA. The position of each sequence is indicated relative to the start codon. Regions identified as being involved in regulation of the genes are highlighted, as are similar regions in other genes. Sites at which protein has been shown to bind are also indicated. ( a ) Barley Amy 32b (Sutcliff et al ., 1993; Whittier et al ., 1987); wheat Amy 2/54 (Huttley et al ., 1992; Rushton et al ., 1992; Rushton et al ., 1995); barley Amy 46 (Khursheed & Rogers, 1988); barley Amy 2/p155 (Knox et al ., 1987); barley aleurain (Whittier et al ., 1987); barley β-glucanase II (Wolf, 1992); wheat cathepsin B-like (Cejudo et al ., 1992); rice ubiquitin-conjugating enzyme (Chen et al ., 1995). ( b ). Wheat Amy 1/18 (Rushton et al ., 1992); barley Amy pHV 19 (Jacobsen & Close, 1991; Gubler & Jacobsen, 1992)/ Amy 1 / 6-4 (Khursheed & Rogers, 1988; Rogers, Lanahan & Rogers 1994); rice OSamy-a / Amy 3c (Ou-Lee et al ., 1988; Sutcliff et al ., 1991; Yu et al ., 1992; Goldman et al ., 1994); rice Amy 3B (Sutcliffe et al ., 1991); rice OSamy-c (Kim et al ., 1992; Kim & Wu, 1992; Tanida et al ., 1994); rice Amy 1A (Huang et al ., 1990; Itoh et al ., 1995).
Figure 4 ( b ). For legend see facing page.  相似文献   

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