scholarly journals Different mRNAs have different nuclear transit times in Dictyostelium discoideum aggregates.

1983 ◽  
Vol 3 (8) ◽  
pp. 1511-1517 ◽  
Author(s):  
G Mangiarotti ◽  
C Zuker ◽  
R L Chisholm ◽  
H F Lodish
Keyword(s):  
Dictyostelium Discoideum ◽  
Repetitive Dna ◽  
Mrna Species ◽  
Processing Times ◽  
Cytoplasmic Rna ◽  
Transit Times ◽  
Different Types ◽  
Nuclear Processing

Nuclear processing of mRNA precursors in differentiating multicellular Dictyostelium discoideum aggregates is markedly slower than in growing amoebae. Thus, we have been able to determine the time of nuclear processing of individual mRNA species in postaggregating cells by following the incorporation of 32PO4 into nuclear and cytoplasmic RNA complementary to cloned cDNAs. Precursors of mRNAs synthesized during both growth and differentiation remain in the nucleus for about 25 to 60 min. By contrast, typical mRNAs which are synthesized only by postaggregative cells have nuclear processing times between 50 and 100 min. Depending on the particular mRNA, between 20 and 60% of nuclear transcripts are converted into cytoplasmic mRNA. A third class of mRNAs are transcribed from a set of repetitive DNA segments and are expressed predominantly during differentiation. Nuclear precursors of these mRNAs are extensively degraded within the nucleus or very rapidly after transport to the cytoplasm. Those sequences that are stable in the cytoplasm exit from the nucleus only after a lag of over 2 h. Thus, mRNAs encoded by different genes that are subject to different types of developmental controls display different times of transit to the cytoplasm and different efficiencies of nuclear processing. Differential nuclear processing may contribute to the regulation of the level of individual cytoplasmic mRNAs.

Different mRNAs have different nuclear transit times in Dictyostelium discoideum aggregates

1983 ◽  
Vol 3 (8) ◽  
pp. 1511-1517
Author(s):  
G Mangiarotti ◽  
C Zuker ◽  
R L Chisholm ◽  
H F Lodish
Keyword(s):  
Dictyostelium Discoideum ◽  
Repetitive Dna ◽  
Mrna Species ◽  
Processing Times ◽  
Cytoplasmic Rna ◽  
Transit Times ◽  
Different Types ◽  
Nuclear Processing

Nuclear processing of mRNA precursors in differentiating multicellular Dictyostelium discoideum aggregates is markedly slower than in growing amoebae. Thus, we have been able to determine the time of nuclear processing of individual mRNA species in postaggregating cells by following the incorporation of 32PO4 into nuclear and cytoplasmic RNA complementary to cloned cDNAs. Precursors of mRNAs synthesized during both growth and differentiation remain in the nucleus for about 25 to 60 min. By contrast, typical mRNAs which are synthesized only by postaggregative cells have nuclear processing times between 50 and 100 min. Depending on the particular mRNA, between 20 and 60% of nuclear transcripts are converted into cytoplasmic mRNA. A third class of mRNAs are transcribed from a set of repetitive DNA segments and are expressed predominantly during differentiation. Nuclear precursors of these mRNAs are extensively degraded within the nucleus or very rapidly after transport to the cytoplasm. Those sequences that are stable in the cytoplasm exit from the nucleus only after a lag of over 2 h. Thus, mRNAs encoded by different genes that are subject to different types of developmental controls display different times of transit to the cytoplasm and different efficiencies of nuclear processing. Differential nuclear processing may contribute to the regulation of the level of individual cytoplasmic mRNAs.

The ribosenucleic acid content of isolated cell nuclei

1952 ◽  
Vol 214 (1118) ◽  
pp. 427-427
Keyword(s):  
Nucleic Acids ◽  
Acid Content ◽  
Isolation Procedure ◽  
Cell Nuclei ◽  
Isolated Nuclei ◽  
Rna Content ◽  
Cytoplasmic Rna ◽  
Different Types ◽  
Isolated Cell

A method is described for the estimation, by furfural formation, of small amounts of ribosenucleic acid (RNA) in the presence of large amounts of deoxyribosenucleic acid. Evidence is produced to show that the Schmidt and Thannhauser method does not give a satisfactory separation of the two types of nucleic acids. The method has been applied to the estimation of the RNA content of nuclei isolated from a number of different types of cell, and the values reported. It is concluded that the nuclei as isolated contain small amounts of RNA, but the possibility of adsorption of cytoplasmic RNA by the nuclei during the isolation procedure cannot be excluded. No correlation was found between the RNA content of the isolated nuclei and the prominence of their nucleolar systems.

scholarly journals DYNAMICS BETWEEN ORDER AND CHAOS IN A SIMPLE REENTRANT MODEL OF PRODUCTION DYNAMICS

2003 ◽  
Vol 13 (05) ◽  
pp. 1343-1351 ◽  
Author(s):  
I. KATZORKE ◽  
A. PIKOVSKY
Keyword(s):  
Autocorrelation Function ◽  
Manufacturing Process ◽  
Processing Times ◽  
Different Types ◽  
One Machine ◽  
Production Dynamics

We consider a simple reentrant model of a manufacturing process, consisting of one machine at which two different types of items have to be processed. The model is completely deterministic: all delivery and processing times are fixed, and are generally incommensurate. Dependent on the arrival and processing times, a queue of waiting items grows, remains constant or disappears. We demonstrate that the dynamics of the system crucially depends on the queue type. Complexity is most observed for the case of growing queue. We characterize this dynamics between order and chaos with the T-entropy and the autocorrelation function.

scholarly journals Study of RBC Histograms and Its Correlation with Etiopathogenesis and Other Parameters in Various Anemias

2021 ◽  
pp. 66-82
Author(s):  
A. P. Gokula Kannan ◽  
R. Govindarajan ◽  
J. Thanka
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Blood Cell ◽  
Red Blood Cell ◽  
Pluripotent Stem Cells ◽  
Morphological Features ◽  
Peripheral Smear ◽  
Smear Examination ◽  
Cytoplasmic Rna ◽  
Different Types

The pluripotent stem cells which are present in the bone marrow renew by its own and differentiate into mature cells. These stem cells undergo division by the presence of erythropoietin, where the nucleus is extruded out from the cell during the end of differentiation, thereby retaining cytoplasmic RNA to form a reticulocyte. The reticulocyte i s a precursor to red blood cell and on losing the RNA it matures into a Red Blood Cell. The present study aimed to analyze the correlation between the automated histogram patterns along with morphological features of RBC‘s prepared from peripheral smear examination in different types of anemia. viz., MCV, MCH, MCHC & RWD- CV.

HISTOCHEMICAL CHANGES IN MELOLONTHA MELOLONTHA (LINNAEUS) (COLEOPTERA) INFECTED BY A NEW VIRUS

1966 ◽  
Vol 12 (5) ◽  
pp. 965-971 ◽  
Author(s):  
Oswald N. Morris
Keyword(s):  
Protein Content ◽  
Nuclear Protein ◽  
Fat Body ◽  
Disease Process ◽  
Cytoplasmic Inclusions ◽  
Virus Particles ◽  
Melolontha Melolontha ◽  
Cytoplasmic Rna ◽  
Different Types ◽  
Histochemical Changes

Changes in DNA, RNA, protein, and glycogen in the fat body of a beetle, Melolontha melolontha (Linnaeus), were studied histochemically at intervals of 15, 23, 75, and 195 days after intrahemocoelic injection of a cytoplasmic polyhedrosis virus, Vagoiavirus melolonthae. As the disease progressed, the average nuclear diameter increased considerably without any apparent change in DNA content. Cytoplasmic RNA increased progressively for about 75 days and then decreased slightly. Nuclear protein content increased during the first 23 days after virus inoculation. Cytoplasmic protein content progressively increased throughout the disease process. There was no significant change in glycogen reserves 23 days after inoculation; thereafter, glycogen was drastically reduced.Three morphologically different types of cytoplasmic inclusions all staining intensely with naphthol yellow S (thus establishing their proteinaceous nature) were observed. The pyroninophilic "round" type is considered to be "mature" inclusions containing the virus particles demonstrated by electron microscopy. The resemblances between this virus and some viruses of higher animals are discussed.

scholarly journals Changes in mRNA levels of the sarcoplasmic/endoplasmic-reticulum Ca2+-ATPase isoforms in the rat soleus muscle regenerating from notexin-induced necrosis

1996 ◽  
Vol 320 (1) ◽  
pp. 107-113 ◽  
Author(s):  
Ernö ZÁDOR ◽  
Luca MENDLER ◽  
Mark VER HEYEN ◽  
László DUX ◽  
Frank WUYTACK
Keyword(s):  
Endoplasmic Reticulum ◽  
Mrna Level ◽  
The Other ◽  
Mrna Levels ◽  
Advanced Stage ◽  
Endoplasmatic Reticulum ◽  
Mrna Species ◽  
Different Types ◽  
Rat Soleus Muscle ◽  
Fast Twitch

The relative mRNA levels corresponding to the different sarcoplasmic/endoplasmic-reticulum Ca2+-ATPase isoforms (SERCA1a, SERCA1b, SERCA2a, SERCA2b and SERCA3) were measured by reverse transcriptase–PCR in rat soleus muscles regenerating after notexin-induced necrosis. The succession of appearance of the different types of SERCA mRNA species in regenerating muscle largely recapitulates those observed during normal ontogenesis. The mRNA levels of the muscle-specific isoforms SERCA1a and SERCA2a became very low on the first and third days after injection of the snake venom. It was only on the fifth day of regeneration that the mRNA of the neonatal variant of the fast-twitch skeletal SERCA1b isoform began to rise, well before the other SERCA transcripts. At 7 and 10 days, i.e. at a time when the new myofibres normally become re-innervated, the mRNA level of SERCA1a and SERCA2a increased markedly, but the fast-twitch skeletal SERCA1a isoform was still the most prominent. On day 21, in the advanced stage of regeneration, a switch in the relative expression levels of SERCA1a and SERCA2a mRNA was observed and the ratio of both isoforms became similar to that found in the normal soleus muscles. This was followed by a decline in the level of all SERCA mRNA species, so that on day 28 the levels of the sarcoplasmic/endoplasmatic-reticulum Ca2+-pump RNAs was again lower but their ratio remained similar to that of the untreated control soleus.

Organization of highly repeated sequences in surface-spread pachytene chromosomes of rye

Genome ◽  
2000 ◽  
Vol 43 (6) ◽  
pp. 945-948 ◽  
Author(s):  
N Cuñado ◽  
J Barrios ◽  
J L Santos
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Repetitive Dna ◽  
Dna Sequences ◽  
Repeated Dna ◽  
Telomeric Sequences ◽  
Different Types ◽  
Surface Spread ◽  
Fish Signal

A method of preparing two-dimensional surface spreads of plant synaptonemal complexes (SCs) associated with fluorescence in situ hybridization (FISH) has been applied to analyze the location and organization of five different highly repeated DNA sequences in rye. Our observations indicate that, depending on the type of sequence, the chromatin displays different types of organization. Telomeric sequences were seen tightly associated with the SC while other repetitive DNA sequences were found to form loops that are associated with SCs only at their bases. On the contrary, the FISH signal of a centromeric satellite had a granular appearance, reflecting that the hybridization occurs only with parts of the chromatin loops.Key words: fluorescence in situ hybridization, meiosis, repetitive DNA, rye, synaptonemal complex.

scholarly journals Major changes in phosphorylation of chromatin-associated non-histone proteins accompany development in the slime mould Dictyostelium discoideum

1985 ◽  
Vol 229 (3) ◽  
pp. 771-778 ◽  
Author(s):  
J H Sinclair ◽  
D Rickwood
Keyword(s):  
Dictyostelium Discoideum ◽  
Blue Staining ◽  
Two Dimensional Gel Electrophoresis ◽  
Transcription Analysis ◽  
Slime Mould ◽  
Coomassie Blue Staining ◽  
Cytoplasmic Rna ◽  
Coomassie Blue ◽  
Protein And Rna Synthesis ◽  
Development Phases

Striking changes in protein and RNA synthesis were shown to accompany development in the slime mould Dictyostelium discoideum. These changes are, at least in part, directly attributable to control at the level of transcription. Analysis of nuclear proteins and their states of phosphorylation by two-dimensional gel electrophoresis and autoradiography showed only minor changes in the species of proteins detectable by Coomassie Blue staining during the vegetative growth and development phases. Major changes, however, were detected in their patterns of phosphorylation, with major differences from the vegetative pattern occurring during both early development (0-2h) and late development (8-12h). These changes coincide with major changes in polypeptide synthesis and in nuclear and cytoplasmic RNA complexity.

scholarly journals A review of the physiology of the canine digestive tract related to the development ofin vitrosystems

1998 ◽  
Vol 11 (1) ◽  
pp. 45-69 ◽  
Author(s):  
Marianne Smeets-Peeters ◽  
Tim Watson ◽  
Mans Minekus ◽  
Robert Havenaar
Keyword(s):  
Small Intestine ◽  
Gastrointestinal Tract ◽  
Digestive Tract ◽  
Healthy Adult ◽  
Human Beings ◽  
Ph Values ◽  
Transit Times ◽  
Food And Nutrition ◽  
Different Types

AbstractFood and nutrition studies in animals and human beings often meet with technical difficulties and sometimes with ethical questions. An alternative to research in living animals is the dynamic multicompartmentalin vitromodel for the gastrointestinal tract described by Minekuset al.(1995) and Havenaar & Minekus (1996). The dynamic conditions that are simulated in this model are peristaltic movements, transit times, pH responses, secretion of enzymes and electrolytes and absorption of nutrients and water. To obtain data for anin vitromodel of the dog gastrointestinal tract, the literature was surveyed for physiological responses to different types of dog food. These included: values of enzyme activities, electrolyte concentrations, gastric emptying and intestinal transit times, pH values, secretion and composition of bile and absorption rates in different parts of the dog gastrointestinal tract. The review focuses on research carried out on healthy, adult dogs of 10–20 kg and on parameters related to the oral cavity, stomach and small intestine. This literature research gives sufficient data on the physiology of the canine digestive tract for the development of anin vitrodynamic model that adequately simulates the functions of the stomach and small intestine of the dog.

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