scholarly journals CHANGES IN PLASTID ULTRASTRUCTURE AND PROTEINS DURING THE DEVELOPMENT OF SQUASH FRUITS

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 591d-591
Author(s):  
Haktae Lim

We first investigated the ultrastructural changes of plastids of two fruit pigment genotypes of squash with isogenic backgrounds (YY and BB). In YY ovaries at anthesis chloroplasts contained granular osmiophilic bodies and a few thylakoids, having two features of chromoplasts and chloroplasts in the same organs. After anthesis grana structure gradually disappeared and the typical membranous chromoplasts formed at fruit maturity. On the other hand, proplastids observed in BB ovaries transformed directly into chromoplasts as fruits matured. The same fruits at different developmental stages were also used for protein analysis to provide the relationship between changes in ultrastructure and in protein profiles during plastid differentiation. SDS-PAGE showed that qualitatively similar total plasstid polypeptides for two lines at all stages of growth even though there were quantitative decreases or increases in the contents of a few polypeptides. Soluble and membrane associated proteins were extracted from total tissue of subepidermis of squash and showed remarkable differences regarding the relative amounts of many protein species from ovaries and mature fruits. Reduced amounts of the large and small subunits of RuBPCO were obvious especially in immature fruits compared with LS and SS of RuBPCO of squash leaves.

1987 ◽  
Vol 105 (1) ◽  
pp. 277-290 ◽  
Author(s):  
J M Aletta ◽  
L A Greene

Chartins are a unique class of three families of microtubule-associated proteins, each consisting of several isoforms possessing varying degrees of phosphorylation. The most highly phosphorylated chartin isoforms are highly enriched in neuronal cell fractions containing microtubules and there is evidence that their phosphorylation may play a role in promoting neurite outgrowth. The present work describes the relationship between the phosphorylation state of chartins and the presence of intact microtubules in long-term cultures of NGF-treated, neurite-bearing PC12 cells. Cultures were depleted of microtubules by exposure to high concentrations of depolymerizing agents for 2-24 h. Radiolabeling of cellular proteins with [32P]orthophosphate or [35S]methionine revealed that both the ongoing and steady-state phosphorylation of chartins is markedly altered under these conditions. Two-dimensional isoelectric focusing by SDS-PAGE of whole cell extracts demonstrated that the more acidic, highly phosphorylated isoforms are diminished with a concomitant increase in the more basic, less phosphorylated isoforms. These phosphorylation changes were relatively specific for the chartins and were not observed for phosphorylated MAP 1.2, phospho-beta-tubulin, or most other phosphoproteins. Thus, the phosphorylation state of chartins, but not of other phosphoproteins, is regulated by the presence of native microtubules. Despite depolymerization of microtubules, neurites remained extended for at least 24 h. Neurite elongation, however, was arrested. Microtubules, therefore, may be required for extension, but not for short-term maintenance of well-established neurites. Taxol, which promotes tubule assembly and stability, does not, conversely, drive phosphorylation of the chartins. Instead, taxol appeared to decrease the turnover of phosphate in microtubule-associated, acidic chartin isoforms. These data suggest several models as to how chartin phosphorylation is regulated in neurite-bearing cells and indicate that phosphorylation of cytoplasmic and microtubule-associated chartins occurs via different mechanisms.


2010 ◽  
Vol 66 (1) ◽  
Author(s):  
Estelle Dannhauser

The article is a lengthy review of the book Jesus’ resurrection in Joseph’s garden by P.J.W. (Flip) Schutte. The book represents a quest to trace the relationship between Jesus’ resurrection, myth and canon. Schutte finds the origin of events underlying the biblical canon in proclamation. His focus in the book is the proclamation of the death and resurrection of Christ, which, in its developmental stages, hinged on the life and death of the historical Jesus. Proclamation developed into a mythical narrative that became the foundational myth for the Christ cult, validating its existence and rituals. With the growth and institutionalisation of the faith community (church), came an increased production of literature, causing the power-wielding orthodoxy to identify a body of literature containing the ‘truth’ and ‘correct teaching’, thus establishing the authoritative canon. In, through, behind and beyond Jesus of Nazareth, Schutte has perceived a canon behind the canon: a God of love. In Jesus, the man of myth with historical roots who has become to us the observable face of God, Schutte confesses the kerygma to open up before him. The proclamation therefore extends an invitation to join in a mythological experience and an encounter with God whose love is preached in the metaphor called Easter.


Reproduction ◽  
2021 ◽  
Vol 162 (3) ◽  
pp. 181-191
Author(s):  
Jessica Ispada ◽  
Aldcejam Martins da Fonseca Junior ◽  
Otávio Luiz Ramos Santos ◽  
Camila Bruna de Lima ◽  
Erika Cristina dos Santos ◽  
...  

Metabolic and molecular profiles were reported as different for bovine embryos with distinct kinetics during the first cleavages. In this study, we used this same developmental model (fast vs slow) to determine if the relationship between metabolism and developmental kinetics affects the levels of acetylation or tri-methylation at histone H3 lysine 9 (H3K9ac and H3K9me3, respectively). Fast and slow developing embryos presented different levels of H3K9ac and H3K9me3 from the earliest stages of development (40 and 96 hpi) and up to the blastocyst stage. For H3K9me3, both groups of embryos presented a wave of demethylation and de novo methylation, although it was more pronounced in fast than slow embryos, resulting in blastocysts with higher levels of this mark. The H3K9ac reprogramming profile was distinct between kinetics groups. While slow embryos presented a wave of deacetylation, followed by an increase in this mark at the blastocyst stage, fast embryos reduced this mark throughout all the developmental stages studied. H3K9me3 differences corresponded to writer and eraser transcript levels, while H3K9ac patterns were explained by metabolism-related gene expression. To verify if metabolic differences could alter levels of H3K9ac, embryos were cultured with sodium-iodoacetate (IA) or dichloroacetate (DCA) to disrupt the glycolytic pathway or increase acetyl-CoA production, respectively. IA reduced H3K9ac while DCA increased H3K9ac in blastocysts. Concluding, H3K9me3 and H3K9ac patterns differ between embryos with different kinetics, the second one explained by metabolic pathways involved in acetyl-CoA production. So far, this is the first study demonstrating a relationship between metabolic differences and histone post-translational modifications in bovine embryos.


1999 ◽  
Vol 202 (20) ◽  
pp. 2823-2830 ◽  
Author(s):  
O. Castanon-Cervantes ◽  
B. Battelle ◽  
M.L. Fanjul-Moles

The present study investigated developmental circadian changes in the content of 5-hydroxytryptamine (5-HT) in two structures proposed to contain pacemakers in crayfish Procambarus clarkii: the cerebral ganglion and the eyestalks. Crayfish (N=260) from three developmental stages were divided into two groups: (1) animals subjected to 12 h:12 h light:dark cycles for 10 days and (2) animals treated as described above, then exposed to 72 h of continuous dim light. Crayfish from both groups were killed at different times of day, and the cerebral ganglion and the eyestalks of each were assayed for 5-HT by reversed-phase HPLC with electrochemical detection. In all stages of development, 5-HT content (expressed as (μ)g g(−)(1)wet mass tissue) showed circadian variations in both structures analyzed; rhythms continued to free-run under constant illumination, and total 5-HT content was higher in the brain (0.581+/−0.36 (μ)g g(−)(1); mean +/− s.e.m.) than in the eyestalks (0.299+/−0.15 (μ)g g(−)(1)). As development advances, the percentage of the rhythm that shows periods of 24 h diminishes, while the percentage of the rhythm that shows periods of 9 to 12 h increases. This seems to indicate that pulsatile variations in 5-HT content are superimposed in a circadian component. The relationship between the 5-HT rhythm and electroretinogram and motor activity rhythms during development is discussed.


2006 ◽  
Vol 66 (1a) ◽  
pp. 85-93 ◽  
Author(s):  
M. I. Hamann

From December 1995 to November 2000, the seasonal maturation of Glypthelmins vitellinophilum Dobbin, 1958, in its definitive host, the frog Lysapsus limellus Cope, 1862, was studied in a subtropical permanent pond in northeastern Argentina. The objectives of this study were: 1) to determine the infrapopulation dynamics of the parasite, analyzing the seasonal maturation cycle throughout the years; and 2) to examine the relationship between the intensity of trematode infection in different developmental stages (recruitment, growth and maturation) and the host's body length. Of a total of 1,400 frogs examined over 60 months (5 years), 38% were found to be infected with G. vitellinophilum, and the intensity of infection was 1-15 trematodes per frog. Specimens of G. vitellinophilum were present in L. limellus throughout the years, but did not show a pronounced seasonal maturation cycle. Possible reasons for these findings are discussed with reference to climatic fluctuations and biotic factors. The infective period of the parasite (stage I) occurred in summer, autumn and spring, coinciding with the time each frog cohort appeared. These infections were found principally in small body sizes (classes 1 and 2) of L. limellus. Juvenile and nongravid specimens of worms (stage II and III) were found in frogs of different body sizes throughout the period of investigation. Gravid specimens of the parasite (stage IV) were generally recorded in autumn, winter and spring, mainly in the bodies of larger frogs. The body length of Trematodes in stages I and IV was significantly and positively correlated with that of the frogs.


2018 ◽  
Vol 11 (2) ◽  
pp. 114-120
Author(s):  
Lilis Maghfuroh

In general, the process of each child's developmental stages is the same, that is the result of the maturation process. But in accomplishment, every child has a different speed.  Based on the initial survey 5 (50%) children doubt in the development. The purpose of this study was to determine the relationship among nutritional status with the development of children age toddler. This research design using correlation analytical method with Cross Sectional approach. The number of 45 samples of children under five with simple random sampling technique with the independent variable of nutritional status and the dependent variable of development, analysis using Spearmen test with ρ <0.05. The test results obtained significant 0.002 (ρ <0.05).  Shows there is a relationship of nutritional status with the development of children age toddler. Mother's efforts to improve the development of toddler age children by improving nutritional status that includes 4 healthy 5 perfect in accordance with the needs of children aged toddler and provides stimulation of development through the provision of educational games and immediately bring the child to health personnel if there is suspected deviation of development


2006 ◽  
Vol 290 (6) ◽  
pp. F1295-F1302 ◽  
Author(s):  
Stan F. J. van de Graaf ◽  
Joost G. J. Hoenderop ◽  
René J. M. Bindels

The epithelial Ca2+ channels TRPV5 and TRPV6 are the most Ca2+-selective members of the TRP channel superfamily. These channels are the prime target for hormonal control of the active Ca2+ flux from the urine space or intestinal lumen to the blood compartment. Insight into their regulation is, therefore, pivotal in our understanding of the (patho)physiology of Ca2+ homeostasis. The recent elucidation of TRPV5/6-associated proteins has provided new insight into the molecular mechanisms underlying the regulation of these channels. In this review, we describe the various means of TRPV5/6 regulation, the role of channel-associated proteins herein, and the relationship between both processes.


2020 ◽  
Vol 75 (5) ◽  
pp. 1182-1186 ◽  
Author(s):  
Kelly M Hines ◽  
Tianwei Shen ◽  
Nathaniel K Ashford ◽  
Adam Waalkes ◽  
Kelsi Penewit ◽  
...  

Abstract Background Glycopeptides (GPs), lipopeptides (LPs) and lipoglycopeptides (LGPs) are related antimicrobials important for the management of invasive MRSA infections. Cross-resistance among these antibiotics in MRSA is well documented, as is the observation that susceptibility of MRSA to β-lactams increases as susceptibility to GPs and LPs decreases (i.e. the seesaw effect). Efforts to understand the relationship between GP/LP/LGP cross-resistance and the seesaw effect have focused on the PBPs, but the role of lipid metabolism has not been investigated. Objectives Since the cell membrane is structurally and metabolically integrated with the cell wall and anchors associated proteins, including PBPs, we examined the relationship between membrane lipid composition and the phenomena of cross-resistance among GPs/LPs/LGPs and the β-lactam seesaw effect. Methods We selected for daptomycin, vancomycin and dalbavancin resistance using the USA300 strain JE2 and evaluated the resulting mutants by WGS, MS-based lipidomics and antimicrobial susceptibility testing to assess the relationship between membrane composition, cross-resistance, and the seesaw effect. Results We observed cross-resistance to GPs/LPs/LGPs among the selected strains and the seesaw effect against various β-lactams, depending on the PBP targets of the particular β-lactam. We found that modification of membrane composition occurs not only in daptomycin-selected strains, but also vancomycin- and dalbavancin-selected strains. Significantly, we observed that the abundance of most phosphatidylglycerols positively correlates with MICs of GPs/LPs/LGPs and negatively correlates with the MICs of β-lactams. Conclusions These studies demonstrate a major association between membrane remodelling, cross-resistance and the seesaw effect.


1980 ◽  
Vol 58 (9) ◽  
pp. 1101-1110 ◽  
Author(s):  
J. Roussaux ◽  
M. Hoffelt ◽  
N. Farineau

Etiolated cotyledons of cucumber (Cucumis sativus L.) were isolated and incubated for 15 h in the dark and 48 h in the light in the presence of 10−6 g/mL 6-benzylaminopurine (6-BAP) or 3.10−6 and 10−5 g/mL cycloheximide (CHX). Cotyledons were permanently maintained on these compounds or transferred from one medium to the other after the dark period or after 6 h of the light. 6-BAP stimulates both chlorophyll synthesis and plastid differentiation. Chlorophyll synthesis is more affected than differentiation in the presence of CHX. Only some thylakoids are present in plastids treated permanently with CHX at 10−5 g/mL. At 3.10−6 g/mL, CHX inhibits the development of the stroma thylakoids and the granal stacks. The effect of CHX is particularly important during the 1st h of light; it is partially reversible. During the treatment with 6-BAP followed by CHX (or conversely), the ultrastructural effect of 10−5 g/mL CHX is removed if 6-BAP is given before the inhibitor. After 48 h the plastid ultrastructure depends particularly on the compound applied during the 1st h of light. 6-BAP and CHX are not competitive during chlorophyllogenesis. 6-BAP increases and CHX decreases the incorporation of 32P into cytoplasmic and etioplastic rRNA during the dark. During the light, 6-BAP increases the incorporation in chloroplastic rRNA only and CHX decreases the incorporation in cytoplasmic rRNA only. The modes of action of CHX and its relations with 6-BAP are discussed.


2020 ◽  
Vol 35 (5) ◽  
pp. 640-640
Author(s):  
K Unjia ◽  
R Bennett ◽  
L Lashley

Abstract Objective This study aimed to examine the relationship between developmental stages and concussions that resulted in amnesia as measured by ImPACT. Method Participants were selected from an archival de-identified sports medicine ImPACT database. The sample (N = 4,200) was primarily male (62.2%) student athletes with ages ranging from 10 to 25 years. Participants were divided into three groups: Young athletes (n = 1,400), Adolescent (n = 1,400), and Adult (n = 1,400). A One-Way ANOVA was conducted to determine the relationship between age group and prevalence of concussions resulting in anterograde or retrograde amnesia. Results The One-Way ANOVA revealed significant differences between age group and anterograde F(2,4197) = 107.449, p &lt; .001 and retrograde amnesia F(2,4197) = 82.949, p &lt; .001. Bonferroni pairwise comparison revealed the adolescent athlete group experienced more concussions that result in both anterograde and retrograde amnesia compared to young and adult athletes. There was no significant difference between young and adult athletes. Additionally, there is a significant difference regarding total games missed following concussion F(2,4197) = 117.723, p &lt; .001, with adolescent athletes missing more games compared to young and adult athletes. Conclusions The findings of this study suggest adolescent athletes tend to experience more amnesia-related concussions compared to young and adult athletes. Additionally, adolescent athletes miss more games following these types of concussions. This study highlights the impact that certain types of concussions have on athletes across the developmental stages. Future research should analyze the cognitive effects of various types of concussions across the developmental stages.


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