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1.
David B. Morton James W. Truman 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1985,157(4):423-432
Summary The action of the peptide, eclosion hormone (EH) on the CNS ofManduca sexta appears to be mediated via the second messenger cGMP. Injections of EH or release of endogenous EH cause a rapid increase in cGMP in the CNS. Cyclic GMP, 8-bromo-cGMP and the phosphodiesterase inhibitors IBMX and theophylline mimic the action of EH in triggering premature ecdysis behavior.The CNS is only sensitive to EH just before ecdysis, both in triggering ecdysis and increasing endogenous cGMP levels. The development of the ability to increase cGMP levels occurs earlier than the behavioral sensitivity and the relative timing of these events is discussed in terms of the likely site for the block in behavioral sensitivity.The steroid hormone 20-hydroxyecdysone is shown to regulate the ability of EH to elevate cGMP levels in the CNS.Abbreviations
AS
anterior shrink
-
CAMP
adenosine 3,5cyclic monophosphate
-
cGMP
guanosine 3,5 cyclic monophosphate
-
CNS
central nervous system
-
EH
eclosion hormone
-
20-HE
20-hydroxyecdysone
-
HPLC
high performance liquid chromatography
-
IBMX
3-isobutyl 1-methyl xanthine
-
OT
oxytocin
-
PDE
phosphodiesterase
-
RIA
radioimmunoassay
-
TB
trace bars 相似文献
2.
P. K. O'Connor B. Reich M. A. Sheridan 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1993,163(5):427-431
Rainbow trout were used to characterize the direct influence of growth hormone on hepatic lipid mobilization in vitro. Liver was removed from fish fasted 72 h, sliced into 1-mm3 pieces and incubated in Hanks' medium containing ovine or salmon growth hormone (0.28 ng·ml-1–28 g·ml-1). Lipid mobilization, resulting from triacylglycerol hydrolysis, was evaluated by fatty acid and glycerol release into culture medium. Control rates of fatty acid release and glycerol release were 0.95±0.16 (mean ± SE) and 0.88±0.28 mol·l-1·mg fresh weight, respectively. Both ovine growth hormone (28 ng·ml-1) and salmon growth hormone (28 ng·ml-1) stimulated fatty acid release into culture medium, increasing rates by 112% and 97%, respectively, during the course of a 24-h incubation. Glycerol release was similarly augmented by growth hormone treatment. Growth hormone-stimulated metabolite release became evident within 12 h and persisted for up to 72 h. The presence of amino acids in the culture medium potentiated the lipolytic action of growth hormone. Ovine growth hormone (28 ng·ml-1) in the presence of amino acids stimulated a 53% increase in fatty acid, and a 108% increase in glycerol, release over rates observed in the absence of amino acids. Salmon growth hormone (28 ng·ml-1) in the presence of amino acids stimulated a 53% increase in fatty acid, and a 44% increase in glycerol, release over rates observed in the absence of amino acids. Ovine growth hormone (28 ng·ml-1) also stimulated gluconeogenesis, as indicated by a 75% increase in phosphoenolpyruvate carboxykinase activity in liver pieces incubated in the presence of amino acids. These results indicate that growth hormone directly stimulates lipid breakdown in the liver of trout and that amino acids potentiate growth hormone-stimulated lipolysis.Abbreviations AA
amino acid(s)
- dGDP
deoxy-guanosine diphosphate
-
ED
50
50% effective dose
- FA
fatty acid(s)
- fw
fesh weight
- GH
growth hormone
- Hepes
4-(2-hydroxyethyl)-1-piperazineethanesulphonic acid
- MS-222
tricaine methanesulfonate
- MEM
minimum essential medium
- oGH
ovine growth hormone
- PEPCK
phosphoenolpyruvate carboxykinase
- PKc
protein kinase C
- rpm
revolutions per minute
- sGH
salmon growth hormone
- TG
triacylglycerol
- w/v
weight per volume
This paper was presented in abstract form at the Annual Meeting of the American Society of Zoologists, Dec. 26–30, 1991, Atlanta, GA 相似文献
3.
The phospholipase C (PLC; EC 3.1.4.3) activity in isolated plasma membranes of light-grown wheat (Triticum aestivum L. cv. Prelude) leaves was investigated. The activity against the polyphosphoinositides was strongly dependent on Ca2+ and was affected by the anionic detergent deoxycholate (DOC). In the presence of 20 M Ca2+ the PLC activity preferred phosphatidylinositol 4,5-bisphosphate (PIP2) over phosphatidylinositol 4-monophosphate (PIP) as a substrate. Instead, with 1 mM Ca2+ the enzyme clearly favoured PIP. In addition, the PIP2-PLC activity was increased by Mg2+ and in the presence of GTP, guanosine 5-(-thio)-triphosphate as well as ATP, CTP, guanosine 5-diphosphate and guanosine 5-(-thio)-diphosphate. Further analysis showed that a molybdate-sensitive phosphatase activity catalysing the dephosphorylation of inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) is also associated with the plasma-membrane vesicles. Dephosphorylation of Ins(1,4,5)P3 was reduced in the presence of GTP or by inclusion of the unspecific phosphatase inhibitor molybdate. The results indicate the presence of a PIP2-PLC activity and the presence of a molybdate-sensitive phosphatase activity in wheat plasma-membrane vesicles.Abbreviations DOC
deoxycholate
- IDPase
inosine 5-diphosphatase
- InsPs
inositol phosphates, the numbering at the end indicates the number of phosphate residues and when their positions on the inositol ring are known they are indicated in parentheses, i.e.
- Ins(1,4,5)P3
inositol 1,4,5-trisphosphate
- PIP
phosphatidylinositol 4-monophosphate
- PIP2
phosphatidylinositol 4,5-bisphosphate
- PLC
phospholipase C
This work was financially supported by grant from the Deutsche Forschungsgemeinschaft (DFG). M. C. Arz gratefully acknowledges the support of a Graduiertenstipendium des Landes Nordrhein-Westfalen (Germany). We wish to thank S. Laden and G.E. Grambow for assistance. 相似文献
4.
The neuropeptide eclosion hormone acts directly on the nervous system of the tobacco hornworm, Manduca sexta, to trigger ecdysis behavior at the end of each molt. Previous studies have shown that the action of eclosion hormone is mediated via the intracellular messenger cyclic GMP. In the present study we have investigated the mechanisms involved in the eclosion hormone-stimulated increases in cyclic GMP. No stimulation of guanylate cyclase was seen in homogenized nervous tissue, suggesting that eclosion hormone does not directly stimulate a membrane-bound form of guanylate cyclase. Nitric oxide synthase inhibitors, N-methylarginine and nitroarginine, had no effect on eclosion hormone-stimulated cyclic GMP levels. By contrast, 4-bromophenacyl bromide, an inhibitor of arachidonic acid release, and nordihydroguaiaretic acid, an inhibitor of arachidonic acid metabolism, almost completely abolished the eclosion hormone-stimulated cyclic GMP increase. We hypothesize that eclosion hormone receptors are coupled to a lipase, activation of which causes the release of arachidonic acid. Either the arachidonic acid directly stimulates the soluble guanylate cyclase or further metabolism of arachidonic acid yields compounds that activate guanylate cyclase. 相似文献
5.
A method for long-term plant regeneration of Phaseolus coccineus L, is described. Shoot-tips and cotyledonary nodes cultured on a Murashige and Skoog medium supplemented with N6-benzylaminopurine, 10 M, and -naphthaleneacetic acid, 1M, formed multiple bud-shoots. These shoots were transferred to medium containing BAP 1 M, NAA 0.1 M, and gibberellic acid 3 M to promote shoot growth and further shoot multiplication. Rooting was achieved in medium with 11 M indole-3-acetic acid. Rooted plants grew to maturity and were fertile. Cultures have maintained their ability to regenerate plants for more than two years. A sample of 30 regenerated plants (R0) was tested for chromosome number, all of them being diploid; seven isozymatic systems were electrophpretically analyzed in 82 R0 regenerated plants. No differences were observed in their electrophoretic patterns in comparison with those shown by seedlings. Histological studies revealed the origin of buds from calluses via organogenesis.Abbreviations BAP
N6-benzylaminopurine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- GA3
gibberellic acid
- IAA
indole-3-acetic acid
- MS
Murashige and Skoog (1962) medium
- NAA
-naphthaleneacetic acid
- ADH
alcohol dehydrogenase
- GOT
glutamic-oxaloacetic transaminase
- MDH
malate dehydrogenase
- 6PGD
6-phosphogluconate dehydrogenase
- PGI
Phosphoglucose isomerase
- PGM
phosphoglucose mutase
- SK
shikimate dehydrogenase 相似文献
6.
Phospholipid metabolism is required for M<Subscript>1</Subscript> muscarinic inhibition of N-type calcium current in sympathetic neurons 总被引:1,自引:0,他引:1
The signal transduction cascade mediating muscarinic receptor modulation of N-type Ca2+ channel activity by the slow pathway has remained incompletely characterized despite focused investigation. Recently we confirmed a role for the G-protein Gq and identified phospholipase C (PLC), phospholipase A2 (PLA2), and arachidonic acid (AA) as additional molecules involved in N-current inhibition in superior cervical ganglion (SCG) neurons by the slow pathway. We have further characterized this signal transduction cascade by testing whether additional molecules downstream of phosphatidylinositol-4,5-bisphosphate (PIP2) are required. The L-channel antagonist nimodipine was bath-applied to block L-current. Pretreating cells with pertussis toxin (PTX) minimized M2/M4 muscarinic receptor inhibition of N-current by the membrane-delimited pathway. Consistent with our previous studies, pharmacologically antagonizing M1 muscarinic receptors (M1Rs), Gq, PLC, PLA2, and AA minimized N-current inhibition by the muscarinic agonist oxotremorine-M (Oxo-M). When cells were left untreated with PTX, leaving the membrane-delimited pathway intact and the same antagonists retested, Oxo-M decreased whole cell currents. Moreover, inhibited currents displayed slowed activation kinetics, indicating intact N-current inhibition by the membrane-delimited pathway. These findings indicate that the antagonists used to block the slow pathway acted selectively. PLA2 cleaves AA from phospholipids, generating additional metabolites. We tested whether the metabolite lysophosphatidic acid (LPA) mimicked the inhibitory actions of Oxo-M. In contrast to AA, applying LPA did not inhibit whole cell currents. Taken together, these findings suggest that the slow pathway requires M1Rs, Gq, PLC, PIP2, PLA2, and AA for N-current inhibition.Abbreviations AA arachidonic acid - BAPTA 1,2-bis(2-aminophenoxy)ethane-N,N,N,N-tetraacetic acid - BSA bovine serum albumin - DAG diacylglycerol - DEDA 7,7-dimethyleicosadienoic acid - ETYA 5,8,11,14-eicosatetraynoic acid - FPL FPL 64176 - IP3 inositol-1,4,5-trisphosphate - L-channel L-type calcium channel - L-current L-type calcium current - LPA lysophosphatidic acid - M1R M1 muscarinic receptor - N-channel N-type calcium channel - N-current N-type calcium current - NMN nimodipine - OAG 1-(cis-9-octadecenoyl)-2-acetyl-sn-glycerol - OPC oleoyloxyethyl phosphorylcholine - Oxo-M oxotremorine methiodide - PIP2 phosphatidylinositol-4,5-bisphosphate - PLC phospholipase C - PLA2 phospholipase A2 - PTX pertussis toxin - SCG superior cervical ganglion 相似文献
7.
Garnham BM Fitzpatrick-Wong S Schunack W Nürnberg B Sorrentino G Parkinson FE Kanfer JN Sitar DS 《Neurochemical research》2002,27(12):1613-1618
Compound 24, an alkyl-substituted amino acid amide, previously found to activate pertussis toxin-sensitive G proteins in cell membranes and membrane protein fractions, was used as a tool to determine the mechanism/location of nicotine inhibition of amyloid peptide-stimulated phospholipase A2 and D activities in a human neuroblastoma cell line, LA-N-2, in vitro. In contrast to our previous findings with amyloid peptide, these phospholipase activations by compound 24 were not inhibited by (–)-nicotine, cholera toxin or tetanus toxin pretreatment. The contrasting activation of these phospholipases by amyloid peptide and compound 24 are discussed. 相似文献
8.
David B. Morton 《Developmental neurobiology》1996,29(3):341-353
The neuropeptide eclosion hormone acts on the nervous system of the tobacco hornworm, Manduca sexta, to increase cyclic guanosine monophosphate (cGMP) levels. In this study I describe the localization of some of the sites where these increases occur. Prior to pupal ecdysis, eclosion hormone stimulates an increase in cGMP in a network of fibers in the transverse nerve of each abdominal ganglion. Double-label experiments with propidium iodide suggest that the cGMP immunoreactivity is primarily localized in neurosecretory nerve endings. The time course of the increase in cGMP immunoreactivity and its requirement for lipid metabolism is similar to that of the cGMP increase measured by radioimmunoassay. The cGMP response in the transverse nerve is stage-specific, occurring prior to pupal ecdysis and not prior to larval or adult ecdysis. © 1996 John Wiley & Sons, Inc. 相似文献
9.
Takako Sakai Jun Imamura 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1992,84(7-8):923-929
Summary We have investigated the fate of the mitochondrial genomes of cybrids derived from donor-recipient protoplast fusion between X-irradiated Raphanus sativus (cms line) and iodoacetamide-treated Brassica napus cv. Westar. Two out of ten fusion products were male-sterile with the diploid chromosome number of B. napus. The mitochondrial (mt) genomes of the cybrids and their progeny were further analyzed by DNA-DNA hybridizaion using the pea mitochondrial ATPase subunit gene (atpA) as a probe. One cybrid, 18-3, had a 3.0 kb fragment characteristic of B. napus and a 2.0 kb non-parental fragment when the BamHI-digested DNA was hybridized with the probe. In the first-backcrossed progeny of this cybrid, the hybridization pattern was not stably inherited. A 4.0 kb radish fragment, not detectable in the cybrid, appeared in one of the BC1 generation siblings, and the 2.0 kb non-parental fragment was lost in another. The hybridization patterns in BC1 progeny siblings of cybrid 12-9 were also varied. The alteration of mtDNA in the cybrid progeny continued to the BC2 generation. There was no clear evidence of a heteroplasmic state or of sub-stoichiometric molecules in the mt genome of cybrid 18-3. A possible cause of the observed alteration in the mt genome is discussed. 相似文献
10.
Carrier-mediated uptake of indole-3-acetic acid (IAA) by microsomal vesicles from Cucurbita pepo L. hypocotyls was strongly inhibited by 2,4-dichlorophenoxyacetic acid (2,4-D; i
50= 0.3 M) but only weakly by 1-naphthylacetic acid (NAA). The fully ionised auxin indol-3-yl methanesulphonic acid also inhibited (i
50=3 M). The same affinity ranking of these auxins for the uptake carrier, an electroimpelled auxin anion-H+ symport, is demonstrable in hypocotyl segments. The specificity of the auxin-anion eflux carrier was tested by the ability of different nonradioactive auxins to compete with [3H]IAA and reduce the stimulation of net radioactive uptake by N-1-naphthylphthalamic acid (NPA), a noncompetitive inhibitor of this carrier. By this criterion, NAA and IAA had comparable affinities, with 2,4-D interaction more weakly. Stimulation of [3H]IAA uptake by NAA, as a result of competition for the efflux carrier, could also be demonstrated when a suitable concentration of 2,4-D was used selectively to inhibit the uptake carrier. However, when [3H]NAA was used, no stimulation of its association with vesicles by NPA, 2,3,5-triiodobenzoic acid, or nonradioactive NAA was found. In hypocotyl segments, [3H]NAA net uptake was much less sensitive to NPA stimulation than was [14C]IAA uptake. The apparent contradictions concerning NAA could be explained by carrier-mediated auxin efflux making a smaller relative contribution to the overall transport of NAA than of IAA. The relationship between carrier specificity as manifested in vitro and the specificity of polar auxin transport is discussed.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- IAA
indole-3-acetic acid
- ION3
mixture of 4 M carbonylcyanide m-chlorophenylhydrazone, nigericin and valinomycin
- IMS
indol-3-yl methanesulphonic acid
- NAA
1-naphthylacetic aci
- NPA
N-1-naphthylphthalamic acid 相似文献
11.
T. Bagarinao R. D. Vetter 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,160(5):519-527
Summary Earlier whole-animal experiments have shown that the California killifish (Fundulus parvipinnis) from tidal marshes is highly tolerant to sulfide while the speckled sanddab (Citharichtys stigmaeus) from the open coast is intolerant to sulfide. In the present paper, we demonstrate that the liver mitochondria of the California killifish detoxify sulfide by oxidizing it to thiosulfate and produce ATP in the process. Sulfide oxidation is obligately and stoichiometrically linked to mitochondrial electron transport to oxygen. Concentrations up to 20 M sulfide stimulate mitochondrial respiration while 50 M sulfide causes half-inhibition. Sulfide oxidation by mitochondria is adversely affected at pH<7.4. ATP production is maximal at 10 M sulfide. The finding of sulfide oxidation coupled to ATP production by killifish mitochondria is unprecedented among vertebrates. In comparison, mitochondria of the specked sanddab oxidize sulfide at a much lower rate. This is the first demonstration of biochemical adaptation to sulfide among coastal marine fishes.Abbreviations
ADP
adenosine diphosphate
-
APHA
American Public Health Association
-
ATP
adenosine triphosphate
-
BSA
bovine serum albumin
-
EGTA
ethyleneglycol-bis-(-aminoethyl-ether) N,N,N,N-tetraacetic acid
-
G-6-PDH
glucose-6-phosphate dehydrogenase
-
HEPES
N-2-hydroxyethylpiperazine-N-2-ethane-sulfonic acid
-
HPLC
high-performance liquid chromatography; mBBr monobromobimane
-
NADP
nicotinamide adenine dinucleotide phosphate, oxidized form
- NADPH
reduced form
-
RCR
respiratory control ratio 相似文献
12.
Marie Doleželová Jaroslav Doležel Milan Neštický 《Plant Cell, Tissue and Organ Culture》1992,31(3):215-221
Axillary bud explants of 11 selected mature waratah clones were established in vitro on a modified Murashige & Skoog medium. Adequate proliferation of axillary shoots was achieved by optimisation of the growth regulator status of the culture medium. For the majority of clones, a three to six times rate of proliferation was achieved with 1.25 M BA and 1.0 M GA3 without the occurrence of abnormalities. The white flowering clone did not respond favourably to the addition of GA3 to the medium.Abbreviations BA
benzyladenine
- GA3
gibberellic acid
- IBA
indole-3-butyric acid
- LSD
least significant difference
- MS
Murashige & Skoog medium 相似文献
13.
In order to produce explants of Mandevilla illustris (Vell) Woodson for the Cerrado in vitro, the Germplasm Bank of UNAERP, we carried out a micropropagation protocol using MS or MS/3 medium supplemented with different concentrations of 6-benzyladeninepurine (BA), Zeatin or 2-isopentenyladenine for nodal segment growth, and -naphthaleneacetic acid, indole-3-butyric acid (IBA) or 1,4 dithiothreitol for rooting. For nodal segments, all the cytokinins tested yielded similar results. However, 2.22 µM BA is more economical to use. MS/3 medium supplemented with 0.49 µM IBA was the most appropriate medium for rooting, resulting in 29% rooted explants. The crude aqueous extract from the subterranean system (SS) of M. illustris was assayed for its inhibitory action on the enzymatic activity of Crotalus durissus terrificus snake venom, isolated basic phospholipase A2 (CB) and crotoxin. It totally inhibited the phospholipase activity of crude Cdt venom and CB toxin and inhibited the phospholipase activity of crotoxin by 49%. The toxic action of both the crude venom and crotoxin was partially inhibited—there was a prolonged survival time and a 40.0% decrease in lethality.Abbreviations
BA:
6-Benzyladeninepurine
-
CB:
Crotalus durissus terrificus basic phospholipase A2
-
Cdt:
Crotalus durissus terrificus crude venom
-
DTT:
1,4 Dithiothreitol
-
IBA:
Indole-3-butyric acid
-
2ip:
2-Isopentenyladenine
-
MiHD:
Minimum indirect hemolytic dose
-
NAA:
-Naphthaleneacetic acid
-
PBS:
Phosphate-buffered saline solution
-
Spermidine:
(n-[3-Aminopropyl]-1,4-butanediamine)
-
SS:
Subterranean system
-
TDZ:
Thidiazuron
-
Zeatin:
(6-[4-Hydroxy-3-methylbut-2-enylamino]purine)
Communicated by C.F. Quiros 相似文献
14.
Mark J. Birnbaum Lawrence I. Gilbert 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,160(2):145-151
Summary The activity of ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis, becomes elevated in intact female Drosophila melanogaster shortly after adult eclosion. This activity reaches a peak at 24 h following eclosion, and then drops to lower levels by 48 h. This pattern is not observed in males, consistent with the hypothesis that polyamine synthesis is involved in ovarian maturation in Drosophila. Abdomens isolated within 2 h of adult eclosion do not display elevated ODC activity or ovarian maturation. However, a 250-ng dose of the juvenile hormone analog methoprene (ZR-515) applied in acetone to these abdomens, recovers ovarian maturation and causes a 5–10 fold increase in enzyme activity over controls treated with acetone alone. The same dose of the inactive precursor methyl farnesoate caused no such increase, whereas a 500-ng dose of the newly discovered natural Drosophila JHB3 stimulated a four-fold response. The response to methoprene was dose-dependent, showing stimulatory activity at a dose as low as 10 ng. This stimulation by JHA is rapid, occurring between 1 and 3 h following hormone treatment, reminiscent of JH induction of fat body vitellogenin synthesis in Drosophila. Elevated ODC activity appeared to be localized in the adult fat body. During embryogenesis, ODC activity remained undetectable until just prior to hatching, when a large increase was detected. We postulate that JH may, either directly or indirectly, regulate polyamine biosynthesis in vivo, and that this synthesis may be required for the production of macromolecules during Drosophila vitellogenesis or embryogenesis.Abbreviations
JH
juvenile hormone
-
JHA
juvenile hormone analog
-
ODC
ornithine decarboxylase
-
SAMDC
S-adenosyl-methionine decarboxylase
-
JHB
3
juvenile hormone III bisepoxide 相似文献
15.
Phenylalanine ammonia-lyase (PAL; EC 4.3.1.5.) induction in cotyledons from 96-h dark-grown Lycopersicon esculentum Mill. was studied in response to continuous light and hourly light pulses (blue, red, far red). The increases of PAL promoted by blue and red pulses are reversed completely by immediately following 758 nm irradiations. The response to continuous red light could be substituted for by hourly 6-min red light pulses. The effect of continuous red treatments is mainly due to a multiple induction effect of phytochrome. In contrast to red light, hourly light pulses with far red and blue, light can only partially substitute for continuous irradiation. The continuous blue response could be due to a combination of a multiple induction response and of a high irradiance response of phytochrome. The continuous far red response, could represent a high irradiance response of phytochrome. Dichromatic irradiations indicate that phytochrome is the photoreceptor controlling the light response (PAL) in tomato seedlings.Abbreviations Norflurazon
NF-4-chloro-5-(methylamino)-2-(,,,-trifluoro-m-tolyl)-3 (2H) pyridazinone
- PAL
phenylalanine ammonia-lyase
-
phytochrome photoequilibrium Pfr/Ptot
- Pfr
far-red absorbing form of phytochrome
- Pr
red absorbing form of phytochrome
- Ptot
total phytochrome: Pr+Pfr 相似文献
16.
Günter Scholz 《Biometals》1989,2(2):89-91
Summary An exogenous supply of nicotianamine is essential for the redistribution of59iron via the symplast and the phloem to newly developing organs in de-rooted seedlings of the nicotianamine-less tomato mutantchloronerva. This observation supports the idea that nicotianamine could function as a translocator of iron within the symplast and the phloem.Abbreviations
EDDHA
ethylenediamine-N,N-bis(o-hydroxy-phenylacetic acid)
-
NA
nicotianamine=(2S, 3S,3S)-N-[N-(3-amino-3-carboxypropyl)-3-amino-3-carboxypropyl]-azetidine-2-carboxylic acid
This paper is part 36 in the seriesThe normalizing factor for the tomato mutant chloronerva. For part 35 see Stephan and Grün (1989) 相似文献
17.
Rosemary S. Gray David P. Muehleisen Eva J. Katahira Walter E. Bollenbacher 《Cellular and molecular neurobiology》1993,13(1):39-58
1. | A 28-kDa peptide from the brain of the tobacco hornworm,Manduca sexta, was purifiedvia HPLC. The peptide copurified with the insect neurohormone, prothoracicotropic hormone (PTTH), through two HPLC columns. |
2. | Immunocyctochemistry using polyclonal antibodies against the 28-kDa peptide revealed that the peptide was produced in the same protocerebral neurons that produce PTTH. Western blot analysis demonstrated that the 28-kDa peptide and big PTTH are different molecules. |
3. | A PTTHin vitro bioassay indicated that despite having chromatographic properties similar to those of big PTTH and being produced by the same neurons, the 28-kDa peptide did not have PTTH activity. |
4. | Amino acid sequence analysis yielded a 27 N-terminal amino acid sequence that had no similarity with known peptides. |
5. | Immunocytochemical studies revealed that the 28-kDa peptide is present as early as 30% embryonic development and is absent by adult eclosion. This is in contrast to big PTTH, which is expressed throughout theManduca life cycle. |
6. | These data suggest that the 28-kDa peptide is another secretory phenotype of the lateral neurosecretory cell group III (L-NSC III) which may have functions distinct from those for big PTTH or may act synergistically with big PTTH. |
18.
Z. Krupa 《Photosynthesis research》1983,4(3):229-239
Thylakoid membranes obtained from bean chloroplasts treated with bean galactolipase or phospholipase A2 (from Crotalus terr. terr.) showed marked changes in their polypeptide patterns when separated on SDS-PAGE. The obtained results have been discussed with regard to the relationship between chloroplast lipids and polypeptides originating from chlorophyll-protein complexes of bean thylakoids. A coexistence between galactolipids and the peripheral antennae in PS I complex and LHCP3 as well as a conspicuous role of phospholipids in PSI and PSII centre chlorophyll-protein complexes has to be underlined.Abbreviations CP1
chlorophyll a-protein complex of PSI
- CPa
chlorophyll a-protein complex of PSII
- D10
digitonin subchloroplast particles enriched in PSII
- D144
digitonin subchloroplast particles enriched in PSI
- DCMU
3-(3,4-dichlorophenyl)-1,1-dimethylurea
- LHCP1–3
light harvesting chlorophyll a/b protein complexes
- PAGE
polyacrylamide gel electrophoresis
- PSI
photosystem I
- PSII
photosystem II
- SDS
sodium dodecyl sulphate
- TCA
trichloroacetic acid
- Tricine
N-Tris-(hydroxymethyl)-methylglycine
- Tris
Tris-(hydroxymethyl)-aminomethan 相似文献
19.
J. Zhang V. K. Tiwari T. J. Golds N. W. Blackhall E. C. Cocking B. J. Mulligan J. B. Power M. R. Davey 《Plant Cell, Tissue and Organ Culture》1995,41(2):125-138
Cat gene expression has been investigated following PEG-mediated plasmid uptake into barley protoplasts. The uptake conditions optimised for transient expression were employed for stable transformation. Transformed protoplast-derived calli of the cvs. Dissa and Igri, were selected on medium containing G418 at 40 g ml–1 or kanamycin sulphate at 250 g ml–1. Absolute transformation frequencies of 28.9×10–5 and 21.3×10–5 were recorded for Dissa with kanamycin sulphate and G418 selection, respectively. The frequency for Igri was 11.5×10–5 with G418 selection. Antibiotic resistant protoplast-derived colonies expressed NPTII activity; Southern hybridisation confirmed integration of the nptII gene into barley genomic DNA.Abbreviations ABA
abscisic acid
- AC-CAP
acetylated chloramphenicol
- BAP
6-benzylaminopurine
-
cat
chloramphenicol acetyltransferase gene
- CAT
chloramphenicol acetyltransferase activity
- CaMV
cauliflower mosaic virus
- CAP
chloramphenicol, 2,4-d-2,4-dichlorophenoxyacetic acid
- GA3
gibberellic acid
- G418
Geneticin
-
gus
-glucuronidase gene
- HEPES
(N[2-hydroxyethyl] piperazine-N-[2-ethanesulphonic acid])
- IAA
indole acetic acid
- MES
2-N-morpholinoethane sulphonic acid
- NAA
-naphthaleneacetic acid
-
npt II
neomycin phosphotransferase gene
- NPTH
neomycin phosphotransferase activity
- PEG
polyethylene glycol
- SCV
settled cell volume 相似文献
20.
Thermotolerance of photosystem II (PSII) in leaves of salt-adapted Artemisia anethifolia L. plants (100–400 mM NaCl) was evaluated after exposure to heat stress (30–45°C) for 30 min. After exposure to 30°C, salt adaptation had no effects on the maximal efficiency of PSII photochemistry (Fv/Fm), the efficiency of excitation capture by open PSII centers (Fv/Fm), or the actual PSII efficiency (PSII). After pretreatment at 40°C, there was a striking difference in the responses of Fv/Fm, Fv/Fm and PSII to heat stress in non-salt-adapted and salt-adapted leaves. Leaves from salt-adapted plants maintained significantly higher values of Fv/Fm, Fv/Fm and PSII than those from non-salt-adapted leaves. The differences in Fv/Fm, Fv/Fm and PSII between non-salt-adapted and salt-adapted plants persisted for at least 12 h following heat stress. These results clearly show that thermotolerance of PSII was enhanced in salt-adapted plants. This enhanced thermotolerance was associated with an improvement in thermotolerance of the PSII reaction centers, the oxygen-evolving complexes and the light-harvesting complex. In addition, we observed that after exposure to 42.5°C for 30 min, non-salt-adapted plants showed a significant decrease in CO2 assimilation rate while in salt-adapted plants CO2 assimilation rate was either maintained or even increased to some extent. Given that photosynthesis is considered to be the physiological process most sensitive to high-temperature damage and that PSII appears to be the most heat-sensitive part of the photosynthetic apparatus, enhanced thermotolerance of PSII may be of significance for A. anethifolia, a halophyte plant, which grows in the high-salinity regions in the north of China, where the air temperature in the summer is often as high as 45°C. 相似文献