The nucleolar cycle in man

1977 ◽  
Vol 25 (1) ◽  
pp. 103-110
Author(s):  
M. Anastassova-Kristeva
Keyword(s):  
Gene Expression ◽  
Mitotic Division ◽  
Tissue Cultures ◽  
Nucleolar Number ◽  
Satellite Chromosomes ◽  
Nucleolar Cycle ◽  
Group D ◽  
Secondary Constrictions ◽  
Nucleolus Organizers

Tissue cultures of human embryonal kidney and ovary were examined. In the nuclei of both tissues, one to ten nucleoli have been found. The maximum number of nucleoli is connected with the gene expression of rDNA of the 10 nucleolus organizers of chromosome pairs Nos. 13, 14, 15, 21 and 22, which have secondary constrictions and are the satellite chromosomes in man. The small percentage of cells with 10, 9 and 8 nucleoli is attributed to the rapid association of 3 of the homologous acrocentrics (perhaps of group D). Two of the satellite (SAT) pairs probably associate later after mitosis. The process of fusion is dynamic, resulting in one interphase nucleous—a manifestation of the association of all SAT chromosomes. Dissociation of the nucleolus occurs upon entering prophase, due to the condensation of the chromosomes and retreat of rDNA to the respective secondary constrictions. As a result, the nucleolar number increases again. The pattern of the nucleolar kinetics within the course of one mitotic division is described.

Ontogeny of clock and KiSS-1 metastasis-suppressor (Kiss1) gene expression in the prepubertal mouse hypothalamus

2017 ◽  
Vol 29 (10) ◽  
pp. 1971 ◽  
Author(s):  
Cassandra C. Yap ◽  
Peter J. Mark ◽  
Brendan J. Waddell ◽  
Jeremy T. Smith
Keyword(s):  
Gene Expression ◽  
Clock Gene ◽  
Quantitative Polymerase Chain Reaction ◽  
Time Of Day ◽  
Metastasis Suppressor ◽  
Aryl Hydrocarbon ◽  
Gonadotrophin Releasing Hormone ◽  
Polymerase Chain ◽  
Group D ◽  
Nuclear Receptor Subfamily

Kisspeptin is crucial for the generation of the circadian-gated preovulatory gonadotrophin-releasing hormone (GnRH)–LH surge in female rodents, with expression in the anteroventral periventricular nucleus (AVPV) peaking in the late afternoon of pro-oestrus. Given kisspeptin expression is established before puberty, the aim of the present study was to investigate kisspeptin and clock gene rhythms during the neonatal period. Anterior and posterior hypothalami were collected from C57BL/6J mice on Postnatal Days (P) 5, 15 and 25, at six time points across 24 h, for analysis of gene expression by reverse transcription–quantitative polymerase chain reaction. Expression of aryl hydrocarbon receptor nuclear translocator-like gene (Bmal1) and nuclear receptor subfamily 1, group D, member 2 (Rev-erbα) in the anterior hypothalamus (containing the suprachiasmatic nucleus) was not rhythmic at P5 or P15, but Bmal1 expression exhibited rhythmicity in P25 females, whereas Rev-erbα expression was rhythmic in P25 males. KiSS-1 metastasis-suppressor (Kiss1) expression did not exhibit time-of-day variation in the anterior (containing the AVPV) or posterior (containing the arcuate nucleus) hypothalami in female and male mice at P5, P15 or P25. The data indicate that the kisspeptin circadian peak in expression observed in the AVPV of pro-oestrous females does not manifest at P5, P15 or P25, likely due to inadequate oestrogenic stimuli, as well as incomplete development of clock gene rhythmicity before puberty.

Yeast RAS2 affects cell viability, mitotic division and transient gene expression in Nicotiana species

1990 ◽  
Vol 14 (5) ◽  
pp. 669-685 ◽  
Author(s):  
Pierre Hilson ◽  
Jocelyne Dewulf ◽  
Fabienne Delporte ◽  
Patrick Install� ◽  
Jean-Marie Jacquemin ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Viability ◽  
Transient Gene Expression ◽  
Mitotic Division ◽  
Nicotiana Species

Comparison between single-cell cultures and tissue cultures as model systems for evaluating the modulation of gene expression by food bioactives

2012 ◽  
Vol 64 (2) ◽  
pp. 194-201
Author(s):  
Elisa Boschetti ◽  
James R. Bacon ◽  
Felicity Meyer ◽  
Vitaliano Tugnoli ◽  
Alessandra Bordoni ◽  
...  
Keyword(s):  
Gene Expression ◽  
Single Cell ◽  
Cell Cultures ◽  
Model Systems ◽  
Tissue Cultures ◽  
Modulation Of Gene Expression

No evidence for HPA reset in adult sheep with high blood pressure due to short prenatal exposure to dexamethasone

2002 ◽  
Vol 282 (2) ◽  
pp. R343-R350 ◽  
Author(s):  
Miodrag Dodic ◽  
Arianne Peers ◽  
Karen Moritz ◽  
Vicky Hantzis ◽  
E. Marelyn Wintour
Keyword(s):  
Gene Expression ◽  
Blood Pressure ◽  
High Blood Pressure ◽  
Hpa Axis ◽  
Receptor Gene ◽  
Adult Offspring ◽  
Significant Difference ◽  
Group D ◽  
Receptor Gene Expression ◽  
Concentration Curves

Exposure of pregnant ewes to dexamethasone, for only 2 days (term ∼150 days) at 27 days of gestation ( group D), results in adult offspring with high blood pressure. In this study, hemorrhage stress has been used to see whether in these animals the responsiveness of the hypothalamo-pituitary-adrenal (HPA) axis is altered. In addition, we studied mineralocorticoid (MR) and glucocorticoid (GR) receptor gene expression in the hippocampus and GR gene expression in the hypothalamus using real-time PCR. Calculated areas under the adrenocorticotropin, arginine vasopressin, and cortisol plasma concentration curves in response to hemorrhage were similar between the control and group D. In addition, there was no significant difference in the expression of MR and GR in the hippocampus or GR in the hypothalamus between the control and group D. Taken together, it is unlikely that reset in the HPA axis plays a major role in this particular model of “programmed” hypertension.

scholarly journals Control of anthocyanin biosynthesis pathway gene expression by eutypine, a toxin fromEutypa lata, in grape cell tissue cultures

2003 ◽  
Vol 160 (8) ◽  
pp. 971-975 ◽  
Author(s):  
Maha Afifi ◽  
Ashraf El-Kereamy ◽  
Valérie Legrand ◽  
Christian Chervin ◽  
Marie-Carmen Monje ◽  
...  
Keyword(s):  
Gene Expression ◽  
Anthocyanin Biosynthesis ◽  
Biosynthesis Pathway ◽  
Tissue Cultures ◽  
Pathway Gene ◽  
Cell Tissue ◽  
Grape Cell

The Nucleolar Organizer in the Mitotic Chromosome Complement Of Xenopus Laevis

1962 ◽  
Vol s3-103 (64) ◽  
pp. 407-409
Author(s):  
J. KAHN
Keyword(s):  
Xenopus Laevis ◽  
Mitotic Chromosome ◽  
Chromosome Complement ◽  
Nucleolar Organizer ◽  
Interphase Nuclei ◽  
Nucleolar Number ◽  
Secondary Constrictions

The mutation which reduces nucleolar number in interphase nuclei of Xenopus laevisalso reduces the number of secondary constrictions in mitotic chromosome complements.

Studies on Nucleolar RNA Synthesis in Drosophila Melanogaster

1972 ◽  
Vol 11 (3) ◽  
pp. 675-687
Author(s):  
H. M. KRIDER ◽  
W. PLAUT
Keyword(s):  
Transcriptional Control ◽  
Rna Synthesis ◽  
Nucleolus Organizer ◽  
The Other ◽  
Wild Type ◽  
Acridine Orange Staining ◽  
Nucleolar Rna ◽  
Secondary Constrictions ◽  
Nucleolus Organizers

Nucleolar RNA synthesis in salivary glands from XX, XY, and XO larvae having different numbers of nucleolus organizers was examined autoradiographically following incubation of the tissues in [3H]uridine. In addition, the presence or absence of secondary constrictions was monitored in neuroblast preparations using acridine orange staining. It was observed that: (1) The rate of nucleolar [3H]uridine incorporation is independent of the number of nucleolus organizers in the cell; (2) nucleolar incorporation in XO tissues is elevated relative to that observed in XX or XY material; and (3) where the number of organizers is in excess of the wild type (2), secondary constrictions form at only 2 of the nucleolus organizer sites. From these and related observations we suggest that there are 2 forms of transcriptional control for nucleolar RNA synthesis. One acts as an on-off control, influencing the formation of secondary constrictions at the nucleolus organizers. The other form modulates rates of transcription at organizers where constrictions have been formed.

scholarly journals Gene expression profiling of the SCN in young and old rhesus macaques

2018 ◽  
Vol 61 (2) ◽  
pp. 57-67 ◽  
Author(s):  
Dominique H Eghlidi ◽  
Selva L Luna ◽  
Donald I Brown ◽  
Vasilios T Garyfallou ◽  
Steven G Kohama ◽  
...  
Keyword(s):  
Gene Expression ◽  
Clock Genes ◽  
Rhesus Macaques ◽  
The Body ◽  
Transcriptional Level ◽  
Activity Levels ◽  
Age Related ◽  
Reverse Strand ◽  
Or Genes ◽  
Group D

In mammals, the suprachiasmatic nucleus (SCN) is the location of a master circadian pacemaker. It receives photic signals from the environment via the retinal hypothalamic tract, which play a key role in synchronizing the body’s endogenously generated circadian rhythms with the 24-h rhythm of the environment. Therefore, it is plausible that age-related changes within the SCN contribute to the etiology of perturbed activity–rest cycles that become prevalent in humans during aging. To test this hypothesis, we used gene arrays and quantitative RT-PCR to profile age-related gene expression changes within the SCN of male rhesus macaques – a pragmatic translational animal model of human aging, which similarly displays an age-related attenuation of daytime activity levels. As expected, the SCN showed high expression of arginine vasopressin, vasoactive intestinal polypeptide, calbindin and nuclear receptor subfamily 1, group D, member 1 (NR1D1) (also known as reverse strand of ERBA (REV-ERBα), both at the mRNA and protein level. However, no obvious difference was detected between the SCNs of young (7–12 years) and old animals (21–26 years), in terms of the expression of core clock genes or genes associated with SCN signaling and neurotransmission. These data demonstrate the resilience of the primate SCN to normal aging, at least at the transcriptional level and, at least in males, suggest that age-related disruption of activity–rest cycles in humans may instead stem from changes within other components of the circadian system, such as desynchronization of subordinate oscillators in other parts of the body.

scholarly journals YB-1 Knockdown Inhibits the Proliferation of Mesothelioma Cells through Multiple Mechanisms

Cancers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2285 ◽  
Author(s):  
Thomas G. Johnson ◽  
Karin Schelch ◽  
Kaitao Lai ◽  
Kamila A. Marzec ◽  
Marina Kennerson ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Death ◽  
Cell Line ◽  
Cell Cycle Control ◽  
Time Lapse ◽  
Bioinformatic Analysis ◽  
Mitotic Division ◽  
Migration And Invasion ◽  
G1 Arrest ◽  
Genetic Landscape

Y-box binding protein-1 (YB-1) is a multifunctional oncoprotein that has been shown to regulate proliferation, invasion and metastasis in a variety of cancer types. We previously demonstrated that YB-1 is overexpressed in mesothelioma cells and its knockdown significantly reduces tumour cell proliferation, migration, and invasion. However, the mechanisms driving these effects are unclear. Here, we utilised an unbiased RNA-seq approach to characterise the changes to gene expression caused by loss of YB-1 knockdown in three mesothelioma cell lines (MSTO-211H, VMC23 and REN cells). Bioinformatic analysis showed that YB-1 knockdown regulated 150 common genes that were enriched for regulators of mitosis, integrins and extracellular matrix organisation. However, each cell line also displayed unique gene expression signatures, that were differentially enriched for cell death or cell cycle control. Interestingly, deregulation of STAT3 and p53-pathways were a key differential between each cell line. Using flow cytometry, apoptosis assays and single-cell time-lapse imaging, we confirmed that MSTO-211H, VMC23 and REN cells underwent either increased cell death, G1 arrest or aberrant mitotic division, respectively. In conclusion, this data indicates that YB-1 knockdown affects a core set of genes in mesothelioma cells. Loss of YB-1 causes a cascade of events that leads to reduced mesothelioma proliferation, dependent on the underlying functionality of the STAT3/p53-pathways and the genetic landscape of the cell.

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