scholarly journals Influence of change in the proportion of H1 histone variants on microsporogenesis and development of male gametophyte in transgenic plants of tobacco (Nicotiana tabacum L.)

2011 ◽  
Vol 72 (1) ◽  
pp. 25-35 ◽  
Author(s):  
Joanna Ślusarczyk ◽  
Andrzej Wierzbicki ◽  
Marcin Przewłoka ◽  
Teresa Tykarska ◽  
Andrzej Jerzmanowski ◽  
...  
Keyword(s):  
Male Gametophyte ◽  
Pollen Grains ◽  
Histone Variants ◽  
Ultrastructural Changes ◽  
Control Group ◽  
H1 Histone ◽  
Nicotiana Tabacum L ◽  
Sterile Pollen ◽  
Different Levels

As continuation of investigations in to the mechanism of the role of the H1 histone, which is a crucial protein component chromosomes of all eukaryotes, transgenic tobacco plants with different levels of the H1 histone variants were examined. Tobacco has six sequential variants of the H1 histone: two major ones (H1A and H1B), constituting ca. 90% of all H1, and four minor ones (H1C, H1D, H1E and H1F), occurring in very small quantities. The following groups of plants were examined: K - control group with a full set of histone variants; -AB -with the A and B variants removed; -ABCD - with the A, B, C and D variants removed; and -CD - with the C and D variants removed. The analysis of microsporogenesis in those plants, based on preparations squeezed in acetoorcein, revealed the asynchronous course of meiosis in -AB and -ABCD plants, occurrence of chromosomal aberration, and, consequently, the formation of sterile pollen grains (accordingly: 84,4% and 81,4%). In -CD plants, the percentage of aberration and sterile pollen grains was similar to the control material. Electron microscope observations of microsporogenesis showed ultrastructural changes. In -AB and -ABCD plants, a major portion of the pollen grains were degraded. The smallest number of degraded pollen grains, in comparison with the control, was found in the -CD group.

scholarly journals Tapetum development in transgenic tobacco (Nicotiana tabacum L.) plants with modlfied level of histone H1 variants

2011 ◽  
Vol 75 (2) ◽  
pp. 95-105
Author(s):  
Joanna Ślusarczyk ◽  
Teresa Tykarska ◽  
Andrzej Wierzbicki ◽  
Andrzej Jerzmanowski
Keyword(s):  
Transgenic Tobacco ◽  
Tapetal Cell ◽  
Histone H1 ◽  
Histone Variants ◽  
Control Group ◽  
Nicotiana Tabacum L ◽  
Fertile Pollen ◽  
Tapetal Cells ◽  
Secretory Tissue

The phenomenon of male sterility has often been observed in investigations on the role of histone H1 in regulation of morphogenetic and cytological processes in transgenic tobacco plants. These changes were accumulated by disturbances in flower development, consisting in lengthening of the pistil style in relation to stamen heads. This prevented pollination and production of seeds. As similar abnormalities occurred also in the present investigations (depending on combination, the sterility% was 84.4 to 19.9, at only 8.1 in the control), the main problem of our investigations was an attempt to explain their reasons. It is commonly known that one of the conditions for formation of fertile pollen is the properly functioning tapetum. Here, we carried out observations of ultrastructure of anther tapetum control cells in respect of abnormalities which occurred during microsporogenesis of transgenic plants with inactivated expression of two major (A, B) and two minor (C, D) histone H1 variants. The investigations were carried out on the following groups of plants: (1) control group with a full set of histone variants (K), (2) with inactivated A and B variants (-AB); (3) with inactivated A, B, C and D variants (-ABCD), (4) with inactivated C and D variants (-CD). It was found that tapetal development was normal in all the investigated groups of plants, and the sequence of changes was similar as in the control. However, certain ultrastructural differences appeared when tapetum functioned as secretory tissue, and in the degeneration phase. In tapetal cell cytoplasm, with participation of rER, lipid bodies were formed, which, having penetrated to the cell surface and to locules, took part in formation of pollen grain sporoderm. Both in the control and in the remaining combination, excluding -ABCD, these bodies looked similar: they were grey, homogenous and surrounded by black jagged deposits. In -ABCD plants, these bodies were more translucent, slightly rarefied, and not surrounded by the deposits. Moreover, in -CD plants, large lipid deposits were frequently observed between remainders of degraded tapetal cells. They did not occur in the control and the remaining combinations.

scholarly journals Effect of Phoenix dactylifera pollen grains suspension in fertility of male rats.

2012 ◽  
Vol 9 (4) ◽  
pp. 575-583
Author(s):  
Baghdad Science Journal
Keyword(s):  
Body Weight ◽  
Prostate Gland ◽  
White Male ◽  
Pollen Grains ◽  
Phoenix Dactylifera ◽  
Male Rats ◽  
Reproductive Efficiency ◽  
Control Group ◽  
Hormonal Levels

This study was conducted to determine the role of Phoenix dactylifera pollen grains suspension in improving reproductive efficiency of white male rats. In thisexperiment 40 adult male rats were divided randomly into five equal groups and by following oral administration:the first group was given Phoenix d. pollen grains suspension with concentration 18 mg/kg body weight daily, the second group was given 54 mg/kg, the third group was given 108 mg/kg and fourth group 216 mg/kg body weight, and the last group which represented a control group administrated distilled water only, the administration continued for 40 consecutive days. The effect of Phoenix d. pollen grains in reproductive efficiency was evaluated depending on some parameters such as: weights of (testes, epididymes, seminal vesicle and prostate gland), Some testes parameters of epididymis sperms (sperms concentration, percentage of both sperms motility and viability and percentage of normal sperms).and measuring of some hormonal levels which affect on spermatogenesis like [Luteinizing hormone(LH), Follicle stimulating hormone(FSH) and Testosterone hormone(T)]. The results showed a significant increase (P

scholarly journals AtPIG-S, a predicted Glycosylphosphatidylinositol Transamidase Subunit, is critical for pollen tube growth in Arabidopsis

2020 ◽  
Author(s):  
Nick Desnoyer ◽  
Greg Howard ◽  
Emma Jong ◽  
Ravishankar Palanivelu
Keyword(s):  
Pollen Tube ◽  
Male Fertility ◽  
Male Gametophyte ◽  
Pollen Grains ◽  
Unexpected Finding ◽  
Gpi Anchor ◽  
Developmental Defects ◽  
Post Translational Modifications ◽  
Gpi Transamidase

AbstractBackgroundGlycosylphosphatidylinositol (GPI) addition is one of the several post-translational modifications to proteins that increase their affinity for membranes. In eukaryotes, the GPI transamidase complex (GPI-T) catalyzes the attachment of pre-assembled GPI anchors to GPI-anchored proteins (GAPs) through a transamidation reaction. A mutation in AtGPI8 (gpi8-2), the putative catalytic subunit of GPI-T in Arabidopsis, is transmitted normally through the female gametophyte (FG), indicating the FG tolerates loss of GPI transamidation. In contrast, gpi8-2 almost completely abolishes male gametophyte (MG) function. Still, the unexpected finding that gpi8-2 FGs function normally requires further investigation. Additionally, specific developmental defects in the MG caused by loss of GPI transamidation remain poorly characterized.ResultsHere we investigated the effect of loss of AtPIG-S, another GPI-T subunit, in both gametophytes. Like gpi8-2, we showed that a mutation in AtPIG-S (pigs-1) disrupted synergid localization of LORELEI (LRE), a putative GAP critical for pollen tube reception by the FG, yet is transmitted normally through the FG. Conversely, pigs-1 severely impaired male gametophyte (MG) function during pollen tube emergence and growth in the pistil. A pPIGS:PIGS-GFP transgene complemented these MG defects and enabled generation of pigs-1/pigs-1 seedlings, but seemingly failed to rescue the function of AtPIG-S in the sporophyte, as pigs-1/pigs-1, pPIGS:PIGS-GFP seedlings died soon after germination.ConclusionsCharacterization of pigs-1 provided further evidence that the FG tolerates loss of GPI transamidation more than the MG and that the MG compared to the FG may be a better haploid system to study the role of GPI-anchoring. pigs-1 pollen develops normally and thus represent a tool in which GPI anchor biosynthesis and transamidation of GAPs have been uncoupled, offering a potential way to study free GPI in plant development. While previously reported male fertility defects of GPI biosynthesis mutants could have been due either to loss of GPI or GAPs lacking the GPI anchor, our results clarified that the loss of mature GAPs underlie male fertility defects of GPI-deficient pollen grains, as pigs-1 is defective only in the downstream transamidation step. Our study also provided further evidence that GPI transamidation is essential in seedling development.

The Role of Peripheral Feedback in Emotional Experience With Music

2004 ◽  
Vol 22 (1) ◽  
pp. 79-115 ◽  
Author(s):  
Nicola Dibben
Keyword(s):  
Positive Emotions ◽  
Emotional Experience ◽  
Physiological Arousal ◽  
Situational Factors ◽  
Control Group ◽  
Body State ◽  
Different Types ◽  
Intensity Of Emotion ◽  
Different Levels

Given evidence from other domains that peripheral feedback can influence emotional experience, two experiments are reported that investigate the role of physiological arousal in determining the intensity and valence of emotion experienced when listening to music. In the first experiment, two groups of participants, with different levels of induced physiological arousal, rated four excerpts of music on 10 emotion scales in terms of the emotion they felt while listening to the music and the emotion they thought the music was intended to express. Participants who had exercised immediately before making the emotion judgments reported more intense experiences of emotion felt while listening to the music than did participants who had relaxed. Arousal manipulation had no effect on ratings of the emotion thought to be expressed by the music. These results suggest that arousal influences the intensity of emotion experienced with music and therefore that people use their body state as information about the emotion felt while listening to music. A second experiment investigated this effect in more detail. Independent groups were used to test three different types of induced arousal, with separate groups for ratings of emotion felt and emotion expressed by the music. Participants who had exercised reported intensified experience of positive emotions, in response to pieces that were positive in valence, than did a control group. The article concludes that body state can influence emotional experience with music and presents this as evidence for the role of personal and situational factors in the emotional experience of music.

An ultrastructural study of pollen development in tomato (Lycopersicon esculentum). II. Pollen maturation

1993 ◽  
Vol 71 (8) ◽  
pp. 1048-1055 ◽  
Author(s):  
P. L. Polowick ◽  
V. K. Sawhney
Keyword(s):  
Lycopersicon Esculentum ◽  
Vegetative Cell ◽  
Generative Cell ◽  
Pollen Grains ◽  
Mature Pollen ◽  
Ultrastructural Changes ◽  
Second Phase ◽  
Cell Cytoplasm ◽  
Pollen Maturation

The maturation of tomato pollen grains encompassed several ultrastructural changes. The generative cell separated from the intine and was free in the cytoplasm of the vegetative cell. This process coincided with the appearance of starch in plastids and the division of elongated mitochondria. This stage was followed by a second phase of vacuolation in the vegetative cell cytoplasm. Starch was still abundant at this stage, as were mitochondria, endoplasmic reticulum (ER), and ribosomes. Lipid droplets were the prominent feature of mature pollen grains. Each droplet was surrounded by rough ER (RER), suggesting the role of RER in lipid accumulation and mobilization. Long stretches of ER were present at early stages of maturation, and stacks of up to 50 strands of RER were abundant in mature pollen. The plastids in mature pollen were devoid of starch and had few internal membranes. Mitochondria were abundant and spherical with parallel cristae. In many cases, the cytoplasm at the periphery of the mature pollen grain was dense, forming a distinct zone, and contained only ER. The generative cell cytoplasm had mitochondria, ER, and actin-like filaments but no plastids. The pollen wall at maturity had a lamellated foot layer, a lightly sculptured tectum, and broad intine. The intine was layered in the region of the pollen aperture. Key words: Lycopersicon esculentum, pollen grains, tomato, ultrastructure.

scholarly journals Histone supply: Multitiered regulation ensures chromatin dynamics throughout the cell cycle

2018 ◽  
Vol 218 (1) ◽  
pp. 39-54 ◽  
Author(s):  
Shweta Mendiratta ◽  
Alberto Gatto ◽  
Genevieve Almouzni
Keyword(s):  
Cell Cycle ◽  
Current Knowledge ◽  
Building Blocks ◽  
Histone Variants ◽  
Cell Fates ◽  
Chromatin Dynamics ◽  
Posttranscriptional Processing ◽  
Cellular Dysfunction ◽  
Different Levels

As the building blocks of chromatin, histones are central to establish and maintain particular chromatin states associated with given cell fates. Importantly, histones exist as distinct variants whose expression and incorporation into chromatin are tightly regulated during the cell cycle. During S phase, specialized replicative histone variants ensure the bulk of the chromatinization of the duplicating genome. Other non-replicative histone variants deposited throughout the cell cycle at specific loci use pathways uncoupled from DNA synthesis. Here, we review the particular dynamics of expression, cellular transit, assembly, and disassembly of replicative and non-replicative forms of the histone H3. Beyond the role of histone variants in chromatin dynamics, we review our current knowledge concerning their distinct regulation to control their expression at different levels including transcription, posttranscriptional processing, and protein stability. In light of this unique regulation, we highlight situations where perturbations in histone balance may lead to cellular dysfunction and pathologies.

Light and ultrastructural study in the propylthiouracil-induced hypothyroid rat heart ventricles and the ameliorating role of folic acid

2012 ◽  
Vol 28 (3) ◽  
pp. 262-270 ◽  
Author(s):  
Ahmed A Massoud ◽  
Afaf El-Atrash ◽  
Ehab Tousson ◽  
Wafaa Ibrahim ◽  
Heba Abou-Harga
Keyword(s):  
Folic Acid ◽  
Acid Group ◽  
Ultrastructural Changes ◽  
Control Group ◽  
Albino Rats ◽  
Muscle Fibres ◽  
Cardiac Damage ◽  
Pubertal Stage ◽  
Group I

Thyroid hormones have marked effects on the growth, development, and metabolic function of virtually all organs and tissues. Thyroid status is an important determinant of cardiovascular function. The present work studied the histopathological and ultrastructural changes in the hypothyroid rat left ventricle at post-pubertal stage, in addition to the ameliorating role of folic acid. A total of 50 male albino rats were randomly divided into 5 groups (group I, control; group II, folic acid; group III, propylthiouracil-induced hypothyroid rats; group IV, co-treatment with folic acid; group V, post-treatment). In order to ensure the hypothyroid state, the level of serum triiodothyronine (T3) and thyroid stimulating hormone (TSH) through the dose period was regularly determined. The TSH levels were significantly higher while T3 levels were significantly lower in hypothyroid rats when compared to control group. The high-performance liquid chromatography analysis showed an increase in homocysteine (Hcy) in the hypothyroid rats group when compared to the control group. The histopathological studies of the ventricle in hypothyroid rats revealed hydrophobic changes in myofibrillar structure with striations, myocardial atrophy, nuclear pyknosis, cytoplasmic vacuoles, and cytoplasmic eosinophilia. Transmission electron micrographs in the myocardium of hypothyroid rats revealed a marked reduction in muscle fibre mass, a marked degeneration of muscle fibres, swollen mitochondria, dilated sarcoplasmic reticulum and more prominent perinuclear oedema observed in the cardiac myocytes. In co-treated hypothyroid rats with folic acid, a regular arrangement of muscle fibres, mild swelling of myofibrillar structure with striations and no continuity with adjacent myofibrils were observed while the post-treated hypothyroid rat with folic acid showed normal architecture of myofibrillar structure with striations and continuity with adjacent myofibrils. In conclusion, our results indicated that folic acid had ameliorative effect against cardiac damage induced by 6- n-propyl-2-thiouracil and the best results were found in case of using the folic acid as an adjuvant therapy after returning to the euthyroid state.

Protective role of quercetin against cisplatin-induced hair cell damage in zebrafish embryos

2015 ◽  
Vol 34 (11) ◽  
pp. 1043-1052 ◽  
Author(s):  
SK Lee ◽  
KH Oh ◽  
AY Chung ◽  
HC Park ◽  
SH Lee ◽  
...  
Keyword(s):  
Hair Cell ◽  
Hair Cells ◽  
Cell Damage ◽  
Protective Role ◽  
Ultrastructural Changes ◽  
Control Group ◽  
Zebrafish Embryos ◽  
Protective Effects ◽  
Hair Cell Damage

Background and objectives: The aim of this study was to evaluate the protective effects of quercetin on cisplatin-induced hair cell damage in transgenic zebrafish embryos. Materials and methods: Five days postfertilization zebrafish embryos were exposed to 1 mM cisplatin and quercetin at 10, 50, 100, or 200 μM for 4 h. Hair cells within neuromasts of the supraorbital, otic, and occipital lateral lines were analyzed by fluorescent microscopy ( n = 10). Survival of hair cells was calculated as the average number of hair cells in the control group that were not exposed to cisplatin. Ultrastructural changes were evaluated using scanning electron microscopy. Results: Hair cell damage in neuromasts was decreased by co-treatment of quercetin and cisplatin (quercetin 100 μM: 8.6 ± 1.1 cells; 1 mM cisplatin only: 5.0 ± 0.5 cells; n = 10, p < 0.05); apoptosis of hair cells examined by special stain was also decreased by quercetin. The ultrastructure of hair cells within neuromasts was preserved in zebrafish by the combination of quercetin (100 μM) and cisplatin (1 mM). Conclusion: In conclusion, quercetin showed protective effects against cisplatin-induced toxicity in a zebrafish model. The results of this study suggest the possibility of a protective role of quercetin against cisplatin-induced apoptotic cell death in zebrafish.

Tryptophan-Niacin Metabolism in Rat with Puromycin Aminonucleoside-Induced Nephrosis

2006 ◽  
Vol 76 (1) ◽  
pp. 28-33 ◽  
Author(s):  
Yukari Egashira ◽  
Shin Nagaki ◽  
Hiroo Sanada
Keyword(s):  
Body Weight ◽  
Urinary Excretion ◽  
Enzyme Activities ◽  
Treated Group ◽  
Control Group ◽  
Puromycin Aminonucleoside ◽  
Low Level ◽  
Key Enzyme

We investigated the change of tryptophan-niacin metabolism in rats with puromycin aminonucleoside PAN-induced nephrosis, the mechanisms responsible for their change of urinary excretion of nicotinamide and its metabolites, and the role of the kidney in tryptophan-niacin conversion. PAN-treated rats were intraperitoneally injected once with a 1.0% (w/v) solution of PAN at a dose of 100 mg/kg body weight. The collection of 24-hour urine was conducted 8 days after PAN injection. Daily urinary excretion of nicotinamide and its metabolites, liver and blood NAD, and key enzyme activities of tryptophan-niacin metabolism were determined. In PAN-treated rats, the sum of urinary excretion of nicotinamide and its metabolites was significantly lower compared with controls. The kidneyα-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) activity in the PAN-treated group was significantly decreased by 50%, compared with the control group. Although kidney ACMSD activity was reduced, the conversion of tryptophan to niacin tended to be lower in the PAN-treated rats. A decrease in urinary excretion of niacin and the conversion of tryptophan to niacin in nephrotic rats may contribute to a low level of blood tryptophan. The role of kidney ACMSD activity may be minimal concerning tryptophan-niacin conversion under this experimental condition.

The Use of Posterior Pericardiotomy Technique to Prevent Postoperative Pericardial Effusion in Cardiac Surgery

2012 ◽  
Vol 15 (2) ◽  
pp. 84 ◽  
Author(s):  
Canturk Cakalagaoglu ◽  
Cengiz Koksal ◽  
Ayse Baysal ◽  
Gokhan Alici ◽  
Birol Ozkan ◽  
...  
Keyword(s):  
Cardiac Surgery ◽  
Heart Surgery ◽  
Artery Bypass ◽  
Pericardial Tamponade ◽  
Anxiety Level ◽  
Control Group ◽  
Echocardiographic Study ◽  
Number Of Patients ◽  
Hospital Stays

<p><b>Aim:</b> The goal was to determine the effectiveness of the posterior pericardiotomy technique in preventing the development of early and late pericardial effusions (PEs) and to determine the role of anxiety level for the detection of late pericardial tamponade (PT).</p><p><b>Materials and Methods:</b> We divided 100 patients randomly into 2 groups, the posterior pericardiotomy group (n = 50) and the control group (n = 50). All patients undergoing coronary artery bypass grafting surgery (CABG), valvular heart surgery, or combined valvular and CABG surgeries were included. The posterior pericardiotomy technique was performed in the first group of 50 patients. Evaluations completed preoperatively, postoperatively on day 1, before discharge, and on postoperative days 5 and 30 included electrocardiographic study, chest radiography, echocardiographic study, and evaluation of the patient's anxiety level. Postoperative causes of morbidity and durations of intensive care unit and hospital stays were recorded.</p><p><b>Results:</b> The 2 groups were not significantly different with respect to demographic and operative data (<i>P</i> > .05). Echocardiography evaluations revealed no significant differences between the groups preoperatively; however, before discharge the control group had a significantly higher number of patients with moderate, large, and very large PEs compared with the pericardiotomy group (<i>P</i> < .01). There were 6 cases of late PT in the control group, whereas there were none in the pericardiotomy group (<i>P</i> < .05). Before discharge and on postoperative day 15, the patients in the pericardiotomy group showed significant improvement in anxiety levels (<i>P</i> = .03 and .004, respectively). No differences in postoperative complications were observed between the 2 groups.</p><p><b>Conclusion:</b> Pericardiotomy is a simple, safe, and effective method for reducing the incidence of PE and late PT after cardiac surgery. It also has the potential to provide a better quality of life.</p>

Sign in / Sign up

Export Citation Format

Share Document