DOCSLIB.ORG

Neurotransmitter Coupling Through Gap Junctions in the Retina

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Neurotransmitter Coupling Through Gap Junctions in the Retina The Journal of Neuroscience, December 15, 1998, 18(24):10594–10602 Neurotransmitter Coupling through Gap Junctions in the Retina David I. Vaney, J. Charles Nelson, and David V. Pow Vision, Touch and Hearing Research Centre, Department of Physiology and Pharmacology, The University of Queensland, Brisbane 4072, Australia Although all bipolar cells in the retina probably use the excita- glycine-uptake inhibitor, carbenoxolone blocks the subsequent tory transmitter glutamate, approximately half of the cone bi- glycine replenishment of the bipolar cells but not the amacrine polar cells also contain elevated levels of the inhibitory trans- cells. Third, intracellular injection of rod amacrine cells with the mitter glycine. Some types of cone bipolar cells make gap-junction permeant tracer Neurobiotin secondarily labels a heterologous gap junctions with rod amacrine cells, which heterogenous population of cone bipolar cells, all of which contain elevated levels of glycine, leading to the hypothesis that show glycine immunoreactivity. Taken together, these findings the bipolar cells obtain their glycine from amacrine cells. Ex- indicate that the elevated glycine in cone bipolar cells is not perimental support for this hypothesis is now provided by three derived by high-affinity uptake or de novo synthesis but is independent lines of evidence. First, the glycine transporter obtained by neurotransmitter coupling through gap junctions GLYT1 is expressed by the glycine-containing amacrine cells with glycinergic amacrine cells. Thus transmitter content may but not by the glycine-containing bipolar cells, suggesting that be an unreliable indicator of transmitter function for neurons only the amacrine cells are functionally glycinergic. Second, the that make heterologous gap junctions. gap-junction blocker carbenoxolone greatly reduces exoge- nous 3H-glycine accumulation into the bipolar cells but not the Key words: gap junction; neurotransmitter coupling; glycine; amacrine cells. Moreover, when the endogenous glycine stores glycine transporter; GLYT1; retina; amacrine cell; bipolar cell; in both cell classes are depleted by incubating the retina with a tracer coupling; Neurobiotin; carbenoxolone; sarcosine Gap junctions between neurons serve two distinct functions (for into depolarizing cone bipolar cells, which then convey the rod review, see Spray, 1996). First, gap junctions are readily perme- signal to the retinal ganglion cells (for review, see Vaney, 1997). able to small ions and thus function as electrical synapses, allow- The AII amacrine cells appear to be functionally glycinergic in ing current carried largely by potassium ions to pass directly that (1) they contain elevated levels of glycine but negligible between neurons. Second, gap junctions are also permeable to amounts of g-aminobutyric acid (Pourcho and Goebel, 1987b; metabolites with molecular weights below ;1000 Da. Such met- Wright et al., 1997), (2) their chemical transmission is blocked by abolic coupling is dependent on molecules diffusing down a the glycinergic antagonist strychnine (Mu¨ller et al., 1988), and (3) concentration gradient, whereas electrical coupling is dependent their output synapses are immunoreactive for the a1 subunit of on ions moving down a potential gradient. It has been shown that the glycine receptor (Sassoe`-Pognetto et al., 1994). Although it gap junctions in various systems are permeable to amino acids appears that all bipolar cells in the retina use the excitatory (Rieske et al., 1975; Finbow and Pitts, 1981; Brissette et al., 1994) transmitter glutamate (for review, see Massey, 1990), approxi- and to many second-messenger molecules, including cyclic nucle- mately half of the cone bipolar cells also contain and accumulate otides, inositol triphosphate, and calcium ions (Tsien and Wein- elevated levels of the inhibitory transmitter glycine (for review, gart, 1976; Brehm et al., 1989; Sa´ez et al., 1989; Kandler and Katz, see Pourcho and Goebel, 1990). It has been proposed that the 1998). The amino acid transmitters glycine (75 Da), glycine in the AII amacrine cells diffuses through the heterolo- g-aminobutyric acid (103 Da), and glutamate (147 Da) should gous gap junctions into the cone bipolar cells (Marc, 1984, 1989; pass readily through neuronal gap junctions, but there is no Cohen and Sterling, 1986; for review, see Vaney, 1994). experimental evidence that neurotransmitter coupling occurs nat- We have tested this hypothesis from three independent per- urally in the nervous system. spectives. First, we examined whether the glycine-containing bi- In the mammalian retina, the extensive gap junctions between polar cells express the high-affinity glycine transporter GLYT1. the rod (AII) amacrine cells and cone bipolar cells (Kolb and Second, we determined whether gap-junction blockers affect the Famiglietti, 1974) potentially provide a pathway for neurotrans- accumulation of glycine by the bipolar cells, both exogenously and mitter coupling. Stimulation of the rod photoreceptors leads to after depletion of the endogenous glycine stores. Third, we ver- depolarization of the AII amacrine cells, and this response is ified directly that the bipolar cells coupled to the AII amacrine transmitted electrically through the heterologous gap junctions cells contain elevated levels of glycine. Received Aug. 26, 1998; revised Sept. 25, 1998; accepted Sept. 30, 1998. MATERIALS AND METHODS This work was supported by the National Health and Medical Research Council (Australia). All experiments were approved by the University of Queensland animal Correspondence should be addressed to Dr. D. I. Vaney, Vision, Touch and experimentation ethics committee and were conducted in accord with the Hearing Research Centre, Department of Physiology and Pharmacology, The Uni- Australian code of practice for the care and use of animals for scientific versity of Queensland, Brisbane 4072, Australia. purposes. Adult pigmented rabbits and Dark Agouti rats were obtained Copyright © 1998 Society for Neuroscience 0270-6474/98/1810594-09$05.00/0 from the University of Queensland Central Animal House. Biochemical Vaney et al. • Neurotransmitter Coupling through Gap Junctions J. Neurosci., December 15, 1998, 18(24):10594–10602 10595 reagents were obtained from Sigma (St. Louis, MO) unless indicated cells showing the capacity to synthesize glycine (Pow, 1998). otherwise. Under these circumstances, the cellular localization of a high- Immunocytochemistry. The GLYT1 antigen was a synthetic peptide (Auspep, Melbourne, Australia) corresponding to the final 15 amino affinity glycine transporter assumes special importance in identi- acids in the C terminus, which is common to both splice variants fying glycinergic neurons. For most neurons, the presence of a (GLYT1a and GLYT1b) (Liu et al., 1993). The peptide (2 mg) was glycine transporter can be inferred from the high-affinity uptake coupled to porcine thyroglobulin (20 mg) using formaldehyde, and a of radiolabeled glycine. However, this does not hold for the guinea pig was immunized by our standard techniques (Pow and Crook, glycine-accumulating cone bipolar cells, which could obtain the 1993). Specificity was initially assessed by Western blotting using homog- enates of retina and spinal cord. This revealed a single immunoreactive exogenous glycine indirectly via the glycine-accumulating AII band with a molecular weight of ;68 kDa, corresponding to the pre- amacrine cells (or vice versa). dicted molecular weight of GLYT1 (Zafra et al., 1995). Dot blots using In the rabbit retina, the immunocytochemical localization of the synthetic peptide coupled to bovine serum albumin demonstrated the high-affinity glycine transporter GLYT1 resulted in specific that the antiserum recognized formaldehyde conjugates of the peptide, ; and that this labeling was abolished after preabsorption of the antiserum labeling of the plasma membranes of 60% of the neurons with the peptide conjugate used for immunization. The rat antiserum located at the inner margin of the inner nuclear layer (the ama- against a formaldehyde conjugate of glycine has been characterized crine sublayer). The GLYT1-immunoreactive cells branched only previously (Pow et al., 1995). Formaldehyde-fixed retinal whole mounts in the inner plexiform layer, confirming that they were amacrine and vibratome sections were double-labeled for GLYT1- and glycine- cells, in agreement with an earlier study on the rat retina (Zafra immunofluorescence, as described elsewhere (Pow et al., 1995; Wright et al., 1997). Images of the preparations were acquired with a Bio-Rad et al., 1995). Whole mounts and transverse sections were double- MRC 600 confocal microscope, analyzed using NIH Image 1.62, and labeled for GLYT1- and glycine-immunofluorescence, which prepared for publication using Adobe Photoshop 4. In most cases, digital were visualized sequentially under a high-power objective using processing was confined to adjusting the origin and slope of the linear fluorescence filter sets that were selective for FITC or Texas Red. input–output curve, thus manipulating the brightness and contrast of the image. In Figure 5, the variations command of Photoshop was used to This revealed that most of the glycine-containing cells in the add red (or green) to the midtones and shadows, and to add cyan (or amacrine sublayer expressed GLYT1, although the levels of im- magenta) to the highlights. munofluorescence varied widely (Fig. 1A–D). Consequently, the Tracer-coupling experiments. The detailed procedures have been de- GLYT1-immunofluorescence
Load more

Recommended publications
  • United States Patent Office Patented Apr
    2,881,193 United States Patent Office Patented Apr. 7, 1959 2 propionic acid, glutamic acid, aspartic acid and the like. 2,881,193 Particularly satisfactory results are obtained in the PURIFICATION OF N-HIGHER FATTY ACED purification of N-higher fatty acyl sarcosine compounds AMDES OF LOWER MONOAMINOCAR such as salts of N-lauroyl sarcosine, N-myristoyl sarcosine BOXYFLIC ACDS and N-palmitoyl sarcosine, e.g., sodium, potassium salts thereof. Morton Batlan Epstein, Linden, N.J., assignor to Colgate While the present invention is broadly applicable to Palmolive Company, Jersey City, N.J., a corporation mixtures of the amide and higher fatty acid material of Delaware as indicated, it is effective particularly with the reaction No Drawing. Application May 9, 1955 product produced in the following manner and results Serial No. 507,177 in an amide material substantially free from soap and the like. Thus, the amide may be formed by condensing 6 Claims. (C. 260-404) a higher fatty acyl halide with a salt of said amino car boxylic acid, which has a primary or secondary amino The present invention relates to a novel process for 5 group, in an aqueous alkaline medium. purifying N-higher. acyl amide compounds. More This condensation reaction may be performed under specifically the invention is of a method for removing various suitable conditions. The reaction may be con impurities of the fatty acid or soap type from compounds ducted by mixing suitable proportions of the reactants which are N-higher fatty amides of lower monoamino in an aqueous medium. In general, the reaction is effected carboxylic acids or salts thereof.
    [Show full text]
  • The Impact of D-Cycloserine and Sarcosine on in Vivo Frontal Neural
    Yao et al. BMC Psychiatry (2019) 19:314 https://doi.org/10.1186/s12888-019-2306-1 RESEARCH ARTICLE Open Access The impact of D-cycloserine and sarcosine on in vivo frontal neural activity in a schizophrenia-like model Lulu Yao1, Zongliang Wang1, Di Deng1, Rongzhen Yan1, Jun Ju1 and Qiang Zhou1,2* Abstract Background: N-methyl-D-aspartate receptor (NMDAR) hypofunction has been proposed to underlie the pathogenesis of schizophrenia. Specifically, reduced function of NMDARs leads to altered balance between excitation and inhibition which further drives neural network malfunctions. Clinical studies suggested that NMDAR modulators (glycine, D-serine, D-cycloserine and glycine transporter inhibitors) may be beneficial in treating schizophrenia patients. Preclinical evidence also suggested that these NMDAR modulators may enhance synaptic NMDAR function and synaptic plasticity in brain slices. However, an important issue that has not been addressed is whether these NMDAR modulators modulate neural activity/spiking in vivo. Methods: By using in vivo calcium imaging and single unit recording, we tested the effect of D-cycloserine, sarcosine (glycine transporter 1 inhibitor) and glycine, on schizophrenia-like model mice. Results: In vivo neural activity is significantly higher in the schizophrenia-like model mice, compared to control mice. D-cycloserine and sarcosine showed no significant effect on neural activity in the schizophrenia-like model mice. Glycine induced a large reduction in movement in home cage and reduced in vivo brain activity in control mice which prevented further analysis of its effect in schizophrenia-like model mice. Conclusions: We conclude that there is no significant impact of the tested NMDAR modulators on neural spiking in the schizophrenia-like model mice.
    [Show full text]
  • Incorporation of Sarcosine Into the Actinomycins Synthesized by Streptomyces Antibioticus
    82 Biochem. J. (1964) 90, 82 Incorporation of Sarcosine into the Actinomycins Synthesized by Streptomyces antibioticus By 0. CIFERRI, A. ALBERTINI AND G. CASSANI Department of Genetics, University of Pavia, Italy (Received 3 April 1963) Sarcosine is an amino acid apparently not Micro-organism. Streptomyces antibioticus (no. 1692 of widely distributed in Nature. As a free amino acid, the Culture Collection of the Botanical Institute of this sarcosine has been demonstrated in the radial University) was maintained on slants ofEmerson's medium caeca of the starfish Astropecten aurantiacus (Emerson, Whiffen, Bohonas & DeBoer, 1946). A suspen- sion of spores from such slants was used to inoculate the (Kossel & Edlbacher, 1915), in the muscles of vegetative medium: soya-bean flour 20 g., glucose 10 g., Elasmobranchii (Tarr, 1958) and in the reindeer tap water 1000 ml. (adjusted to pH 7-4 with N-NaOH). The moss, Cladonia itlvatica (Linko, Alfthan, Miettinen culture was incubated at 280 for 48 hr. on an alternating & Virtanen, 1953). Sarcosine has been found shaker. The cells were recovered by centrifuging in the bound in peptides in the antibiotics of the actino- cold, washed twice with the fermentation medium (see mycin (Dalgliesh, Johnson, Todd & Vining, 1950) below) and suspended in the same solution to give a cell and etamycin (Sheehan, Zachau & Lawson, 1957) concentration twice that of the vegetative-medium suspen- groups. The reported presence of sarcosine in the sion. A portion (5 ml.) of this suspension was used to hydrolysate of groundnut protein (Haworth, inoculate 100 ml. of the synthetic galactose-glutamic acid ('fermentation') medium (Katz & Goss, 1960).
    [Show full text]
  • 230 Subpart K—Indirect Discharge Point Sources
    § 414.110 40 CFR Ch. I (7±1±00 Edition) [52 FR 42568, Nov. 5, 1987, as amended at 58 PSES and PSNS 1 FR 36893, July 9, 1993] Maximum Effluent characteristics Maximum for any for any monthly Subpart KÐIndirect Discharge one day average Point Sources Acenaphthene ................................... 47 19 Anthracene ........................................ 47 19 SOURCE: 58 FR 36893, July 9, 1993, unless Benzene ............................................ 134 57 otherwise noted. Bis(2-ethylhexyl) phthalate ................ 258 95 Carbon Tetrachloride ......................... 380 142 § 414.110 Applicability; description of Chlorobenzene .................................. 380 142 Chloroethane ..................................... 295 110 the subcategory of indirect dis- Chloroform ......................................... 325 111 charge point sources. Di-n-butyl phthalate ........................... 43 20 1,2-Dichlorobenzene .......................... 794 196 The provisions of this subpart are ap- 1,3-Dichlorobenzene .......................... 380 142 plicable to the process wastewater dis- 1,4-Dichlorobenzene .......................... 380 142 charges resulting from the manufac- 1,1-Dichloroethane ............................ 59 22 ture of the OCPSF products and prod- 1,2-Dichloroethane ............................ 574 180 1,1-Dichloroethylene .......................... 60 22 uct groups defined by § 414.11 from any 1,2-trans-Dichloroethylene ................. 66 25 indirect discharge point source. 1,2-Dichloropropane .........................
    [Show full text]
  • A Pilot Open-Label Trial of Use of the Glycine Transporter I Inhibitor
    nal atio Me sl d n ic a in r e T Yang, et al., Transl Med (Sunnyvale) 2014, 4:2 Translational Medicine DOI: 10.4172/2161-1025.1000127 ISSN: 2161-1025 Research Article Open Access A Pilot Open-Label Trial of Use of the Glycine Transporter I Inhibitor, Sarcosine, in High-Functioning Children with Autistic Disorder Pinchen Yang1, Hsien-Yuan Lane2, Cheng-Fang Yen1, Chen-Lin Chang 3,4* 1Department of Psychiatry, College of Medicine, Kaohsiung Medical University and Kaohsiung Medical University Hospital, Kaohsiung, Taiwan 2Institute of Clinical Medical Science & Departments of Psychiatry, China Medical University and Hospital, Taichung, Taiwan 3Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University and Kaohsiung Medical University Hospital, Kaohsiung, Taiwan 4Department of Psychiatry, Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan *Corresponding author: Chen-Lin Chang, 100, Shin Chuan 1 st Rd, Kaohsiung 807, Taiwan, Graduate Institute of Medicine, Kaohsiung Medical University and Kaohsiung Medical University Hospital & Department of Psychiatry, Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan, Tel:+886-9-36360220; Fax: +886-7-3134761; E-mail: [email protected] Rec date: Apr 01, 2014; Acc date: Apr 17, 2014; Pub date: Apr 22, 2014 Copyright: © 2014 Yang P et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract This open-label trial examined the efficacy and safety of a glycine transporter I inhibitor, sarcosine, in the 24-week treatment of high-functioning children with autistic disorder.
    [Show full text]
  • Review of Toluene Actions: Clinical Evidence, Animal Studies, and Molecular Targets
    Ashdin Publishing Journal of Drug and Alcohol Research ASHDIN Vol. 3 (2014), Article ID 235840, 8 pages publishing doi:10.4303/jdar/235840 Review Article Review of Toluene Actions: Clinical Evidence, Animal Studies, and Molecular Targets Silvia L. Cruz,1 Mar´ıa Teresa Rivera-Garc´ıa,1 and John J. Woodward2 1Department of Pharmacobiology, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN), Calzada de los Tenorios 235, Col. Granjas Coapa, 14330 Mexico, DF, Mexico 2Department of Neurosciences, Medical University of South Carolina, Charleston, SC 29425, USA Address correspondence to Silvia L. Cruz, [email protected] Received 11 December 2013; Accepted 31 December 2013 Copyright © 2014 Silvia L. Cruz et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract It has long been known that individuals will engage in voluntary inhalation of volatile solvents for their rewarding effects. However, research into the neurobiology of these agents has lagged behind that of more commonly misused drugs such as psychostimu- lants, alcohol, and nicotine. This imbalance has begun to shift in recent years as the serious effects of misused inhalants, especially among children and adolescents, on brain function and behavior have become appreciated and scientifically documented. In this review, we discuss the physicochemical and pharmacological properties of toluene, a rep- resentative member of a large class of organic solvents commonly used as inhalants. This is followed by a brief summary of the clinical and preclinical evidence showing that toluene and related solvents produce significant effects on brain structures and processes involved in the rewarding aspects of drugs.
    [Show full text]
  • C4cc08387c1.Pdf
    Electronic Supplementary Material (ESI) for ChemComm. This journal is © The Royal Society of Chemistry 2014 Supporting Information for Chem. Commun. The Formation of Biodegradable Micelles from a Therapeutic Initiator for Enzyme-Mediated Drug Delivery Mthulisi Khuphea, Algy Kazlauciunasa, Martin Huscrofta and Paul D. Thornton*a School of Chemistry, the University of Leeds, LS2 9JT, U. K. Materials Triphosgene (98%), anhydrous ethyl acetate (99.8%), anhydrous tetrahydrofuran (THF) (≥99.9%), n-hexane (98%), anhydrous N,N-dimethylformamide (DMF) (99.8%), diethyl ether (99.8%) and the amino acids used were all acquired from Sigma Aldrich, U. K. α-Pinene (98%) and phosphate buffered saline (PBS) buffer (Dulbecco ‘A’ tablets) were supplied by Thermo Fisher Scientific Laboratories. Dopamine Hydrochloride (99%) was supplied by Alfa Aesar. HPLC grade water was supplied by VWR International. Instrumentation 1H NMR spectra were recorded at 500 MHz on a Brucker Avance 500 spectrometer, in DMSO-d6 at 25 °C, and analysed using the MestreNova® Research Lab software. The melting range of the NCAs were recorded using a Griffin Edulab 12/04/082 melting point apparatus. pH measurements were done using a Thermo Scientific pH/ mV/temperature meter UY-58800-04 and studies of the dopamine release from micelles were performed on an Agilent Infinity 1260 Series HPLC equipped with a C18 column and photodiode array UV detector. Scanning electron microscopy (SEM) studies were carried out using a JEOL JSM- 6610LV microscope. Dynamic light scattering studies (DLS) were performed using Zetasizer Nano ZS series instrument equipped with a 4 mW He-Ne laser operated at a wavelength of 633 nm.
    [Show full text]
  • Comparison of DNA Isolation Protocols from Soybean Abstract
    Revista Mexicana de Ciencias Agrícolas volume 9 number 8 November 12 - December 31, 2018 Article Comparison of DNA isolation protocols from soybean Luis Felipe Guzmán Rodríguez§ Moisés Alberto Cortés Cruz Juan Manuel Pichardo González Ramón Ignacio Arteaga Garibay 1National Center for Genetic Resources-INIFAP. Boulevard of Biodiversity 400, Tepatitlán de Morelos, Jalisco, Mexico. ZC. 47600. Tel. 01 (800) 0882222, ext. 84823. ([email protected]; [email protected]; [email protected]). §Corresponding author: [email protected]. Abstract The low efficiency of some nucleic acid extraction protocols and the high cost of commercial products, derives in the comparison between methods. In the present work three DNA extraction methods were compared from soybean, to obtain nucleic acids of adequate concentration and quality for PCR amplification. The protocols studied included the methods with 1% and 3% CTAB solutions, with 1% sarcosine and with phenol/chloroform. The experiments were carried out in the DNA and Genomics laboratory of the National Genetic Resources Center-INIFAP. The yield, purity, integrity and functionality of the obtained nucleic acids were evaluated. In all methods, adequate DNA yield was achieved, however, the required purity of the material was only obtained with the phenol/chloroform solution. With the methods of CTAB at 1% and 3% and sarcosine, PCR inhibiting substances were observed, while, with phenol/chloroform, the values of the A260/280 ratio were in a range of 1.96 to 2.00 and the A260/230 ratio in a range of 1.75 to 2.44, with significant differences (p< 0.0001) with the rest of the methods, in addition, the DNA was of high molecular weight and the rbcL gene was amplified by PCR in all the samples.
    [Show full text]
  • A Comparison of Different Algorithms of Sarcosine in Urine
    Prostate Cancer and Prostatic Diseases (2011) 14, 166–172 & 2011 Macmillan Publishers Limited All rights reserved 1365-7852/11 www.nature.com/pcan ORIGINAL ARTICLE Efforts to resolve the contradictions in early diagnosis of prostate cancer: a comparison of different algorithms of sarcosine in urine D-L Cao1,2, D-W Ye1,2, Y Zhu1,2, H-L Zhang1,2, Y-X Wang3 and X-D Yao1,2 1Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China; 2Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China and 3Phase I clinical laboratory, Fudan University Shanghai Cancer Center, Shanghai, China Controversial data on sarcosine as a promising biomarker for prostate cancer (PCa) detection are present. The objective was to clarify these discrepancies and reevaluate the potential value of sarcosine in PCa. Sarcosine algorithms (supernatant and sediment sarcosine/creatinine, supernatant and sediment log2 (sarcosine/alanine)) in urine samples from 71 untreated patients with PCa, 39 patients with no evidence of malignancy (NEM) and 20 healthy women and men were quantified by liquid chromatography/tandem mass spectrometry. Although any sarcosine algorithms were significantly higher in PCa patients than in NEM patients (all Po0.05), comparable sarcosine values were measured in healthy women and men. Additionally, neither biopsy Gleason score nor clinical T-stage were correlated with sarcosine algorithms (all P40.05), and receiver operating characteristic curve analysis indicated that the diagnostic power of any of sarcosine algorithms was nonsignificantly higher than that of serum and urine PSA, but nonsignificantly lower than prostate cancer antigen 3 (PCA3) and the percent-free PSA (%fPSA).
    [Show full text]
  • Glycine Conversion to Sarcosine in the Aposymbiotic Weevil Sitophilus Oryzae L
    Symbiosis, 12 (1992) 261-274 261 Balaban, Philadelphia/Rehovot Glycine Conversion to Sarcosine in the Aposymbiotic Weevil Sitophilus oryzae L. B. DE LA CHAPELLE, J. GUILLAUD and P. NARDON Laboratoire de Biologie, UAINRA 227, INSA 406, 69621 Villeurbanne Cedez France Tel. (33-) 72438356, Fax (33-) 72438511 Received October 16, 1991; Accepted May 27, 1992 Abstract 14C-glycine was incorporated into the diet of an aposymbiotic strain of Sitophilus oryzae larvae and resulted in the labelling of sarcosine, a methylated amino acid uncommon in insects, in 90% of the larvae analyzed. The total sarcosine amount significantly increased as a function of the larval mean weight. If measured in larvae which received not only 14C-glycine but also unlabelled methionine, the total amount of sarcosine was significantly higher in larvae whose diet was sup• plemented by methionine compared to those with a normal diet. The early pupae showed a net significant decrease of the sarcosine level. All the results obtained confirmed those of Gasnier-Fauchet et al. (1986) and showed that sar• cosine is .synthesized by the methylation of glycine in an aposymbiotic strain of Sitophilus oryzae. Keywords: sarcosine, symbiosis, Sitophilus oryzae, methylation, glycine 1. Introduction In the destructive grain weevils Sitophilus, symbiosis was first described by Pierantoni (1927). Symbiotic bacteria were found at all stages of development (Mansour, 1930, 1934; Musgrave, 1964; Nardon, 1971). In larvae, the bacteria are harboured in a specialized organ called bacteriome. Their number is genet• ically controlled by the host (Nardon and Grenier, 1989). Viable aposymbiotic strains of Sitophilus have been obtained in our laboratory from some symbi• otic strains by keeping imagos at 35°0 and 90% relative humidity for about 0334-5114/92 /$03.50 @1992 Balaban l 262 B.
    [Show full text]
  • Amino Acid Analysis
    Agilent Biocolumns Amino Acid Analysis "How-To" Guide Amino Acid Analysis: “How-To” Guide Accurate results with AdvanceBio end-to-end solution The Agilent AdvanceBio Amino Acid Analysis (AAA) end-to-end solution optimizes workflow efficiency by combining the advantages of the Agilent InfinityLab LC Series instrumentation and column technology with proven precolumn derivatization chemistry. It is part of the AdvanceBio family that delivers consistent, exceptional performance for the complete characterization of proteins, antibodies, conjugates, new biological entities, and biopharmaceuticals. This complete, single vendor solution (including The AdvanceBio AAA solution has evolved from proven chemicals/standards, columns, and application support) Agilent ortho-phthalaldehyde/ 9-fluorenyl-methyl provides fast, sensitive, and automated amino acid chloroformate (OPA/FMOC) reagents for amino acid analysis. It is based on the latest InfinityLab LC Series derivatization. Together with AdvanceBio AAA columns instrument and column technology. The automated and standards, these reagents provide an ideal, online derivatization in the Agilent 1290/1260 Infinity II quantitative and qualitative amino acid analysis that vialsampler eliminates tedious manual procedures and combines speed and sensitivity. When used according to delivers reproducible reaction results. AdvanceBio AAA the protocol described in this document, the AdvanceBio columns provide the speed and resolution of sub-2 μm AAA solution enables the user to separate the amino acids columns,
    [Show full text]
  • CAS Number Index 255
    CASNumber Index CAS numbers of the substances listed in Sections II to XV and on the yellow pages CAS number Substance 50-00-0 Formaldehyde 50-29-3 DDT (Dichlorodiphenyltrichloroethane) 50-32-8 Benzo[a]pyrene (pyrolysis product) 50-53-3 Chlorpromazine (2-Chloro-10-(3-dimethylaminopropyl)phenothiazine) 51-75-2 N-Methyl-bis(2-chloroethyl)amine (nitrogen mustard) 51-79-6 Carbamic acid ethyl ester 52-51-7 2-Bromo-2-nitro-1,3-propanediol 53-70-3 Dibenz[a,h]anthracene (pyrolysis product) 54-11-5 Nicotine 54-64-8 Thimerosal 55-18-5 N-Nitrosodiethylamine 55-38-9 Fenthion 55-63-0 Nitroglycerin 56-23-5 Carbon tetrachloride 56-24-6 Trimethyltinhydroxide (TMTOH) (Methyltin compounds) 56-35-9 Bis(tributyltin)oxide (Tri-n-butyltin compounds) 56-38-2 Parathion 56-55-3 Benz[a]anthracene (pyrolysis product) 56-81-5 Glycerin 57-10-3 Palmitic acid 57-11-4 Stearic acid 57-14-7 1,1-Dimethylhydrazine 57-24-9 Strychnine 57-55-6 Propylene glycol 57-57-8 b-Propiolactone 57-74-9 Chlordane 58-89-9 Lindane (g-Hexachlorocyclohexane) 59-50-7 p-Chloro-m-cresol 59-89-2 N-Nitrosomorpholine 60-00-4 Ethylenediaminetetraacetic acid (EDTA) 60-09-3 p-Aminoazobenzene 60-12-8 2-Phenylethanol 60-29-7 Ethyl ether 60-34-4 Monomethylhydrazine 60-35-5 Acetamide 60-57-1 Dieldrin 61-82-5 Amitrole 62-23-7 4-Nitrobenzoic acid (yellow pages) 62-50-0 Methanesulfonic acid ethyl ester (yellow pages) 62-53-3 Aniline 62-56-6 Thiourea 62-73-7 Dichlorvos (DDVP) 62-74-8 Sodium fluoroacetate 62-75-9 N-Nitrosodimethylamine 63-25-2 Carbaryl 64-02-8 Ethylenediaminetetraacetic acid tetrasodium salt (Na EDTA) (yellow pages) 64-17-5 Ethanol 64-18-6 Formic acid 64-19-7 Aceticacid 64-67-5 Diethylsulfate List of MAK and BATValues 2015.DFG,Deutsche Forschungsgemeinschaft Copyright 2015 WILEY-VCH Verlag GmbH &Co.
    [Show full text]