Stimulation of tubulin gene transcription by deciliation of sea urchin embryos

1987 ◽  
Vol 7 (12) ◽  
pp. 4238-4246
Author(s):  
Z Y Gong ◽  
B P Brandhorst
Keyword(s):  
Gene Transcription ◽  
Sea Urchin ◽  
Elevated Level ◽  
Elevated Concentration ◽  
Tubulin Gene ◽  
Lytechinus Pictus ◽  
Tubulin Genes ◽  
Tubulin Mrna ◽  
Hypertonic Shock ◽  
Stimulation Of

Deciliation by hypertonic shock of embryos of the sea urchin Lytechinus pictus resulted in an increase in synthesis of alpha- and beta-tubulins, the consequence of an increased concentration of RNA encoding the tubulins. RNA run-on assays in isolated nuclei indicated that this response is due to a transient increase in the rate of synthesis of tubulin RNA beginning within 5 min of deciliation. This enhancement of tubulin gene transcription also occurred in deciliated embryos treated with the microtubule-depolymerizing agent colcemid; thus the reaction to deciliation is not a response to a reduction in concentration of unpolymerized tubulin utilized for ciliogenesis. In deciliated embryos treated with colcemid, the elevated level of tubulin RNA declined rapidly, due to its destabilization by the elevated concentration of unpolymerized tubulin. The increased transcription of tubulin genes is a response to the loss of cilia, not to the hypertonic shock, and occurs even when cilium regeneration is prevented. Inhibition of protein synthesis with puromycin or emetine did not prevent the transcriptional enhancement but stabilized tubulin mRNA, resulting in increased accumulation of tubulin mRNA after deciliation.

scholarly journals Stimulation of tubulin gene transcription by deciliation of sea urchin embryos.

1987 ◽  
Vol 7 (12) ◽  
pp. 4238-4246 ◽  
Author(s):  
Z Y Gong ◽  
B P Brandhorst
Keyword(s):  
Gene Transcription ◽  
Sea Urchin ◽  
Elevated Level ◽  
Elevated Concentration ◽  
Tubulin Gene ◽  
Lytechinus Pictus ◽  
Tubulin Genes ◽  
Tubulin Mrna ◽  
Hypertonic Shock ◽  
Stimulation Of

Deciliation by hypertonic shock of embryos of the sea urchin Lytechinus pictus resulted in an increase in synthesis of alpha- and beta-tubulins, the consequence of an increased concentration of RNA encoding the tubulins. RNA run-on assays in isolated nuclei indicated that this response is due to a transient increase in the rate of synthesis of tubulin RNA beginning within 5 min of deciliation. This enhancement of tubulin gene transcription also occurred in deciliated embryos treated with the microtubule-depolymerizing agent colcemid; thus the reaction to deciliation is not a response to a reduction in concentration of unpolymerized tubulin utilized for ciliogenesis. In deciliated embryos treated with colcemid, the elevated level of tubulin RNA declined rapidly, due to its destabilization by the elevated concentration of unpolymerized tubulin. The increased transcription of tubulin genes is a response to the loss of cilia, not to the hypertonic shock, and occurs even when cilium regeneration is prevented. Inhibition of protein synthesis with puromycin or emetine did not prevent the transcriptional enhancement but stabilized tubulin mRNA, resulting in increased accumulation of tubulin mRNA after deciliation.

Metabolic importance of Na+/K+-ATPase activity during sea urchin development.

1997 ◽  
Vol 200 (22) ◽  
pp. 2881-2892 ◽  
Author(s):  
P Leong ◽  
D Manahan
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Sea Urchin ◽  
Sodium Pump ◽  
Sea Water ◽  
Strongylocentrotus Purpuratus ◽  
Lytechinus Pictus ◽  
Stimulation Of

Early stages of animal development have high mass-specific rates of metabolism. The biochemical processes that establish metabolic rate and how these processes change during development are not understood. In this study, changes in Na+/K+-ATPase activity (the sodium pump) and rate of oxygen consumption were measured during embryonic and early larval development for two species of sea urchin, Strongylocentrotus purpuratus and Lytechinus pictus. Total (in vitro) Na+/K+-ATPase activity increased during development and could potentially account for up to 77 % of larval oxygen consumption in Strongylocentrotus purpuratus (pluteus stage) and 80 % in Lytechinus pictus (prism stage). The critical issue was addressed of what percentage of total enzyme activity is physiologically active in living embryos and larvae and thus what percentage of metabolism is established by the activity of the sodium pump during development. Early developmental stages of sea urchins are ideal for understanding the in vivo metabolic importance of Na+/K+-ATPase because of their small size and high permeability to radioactive tracers (86Rb+) added to sea water. A comparison of total and in vivo Na+/K+-ATPase activities revealed that approximately half of the total activity was utilized in vivo. The remainder represented a functionally active reserve that was subject to regulation, as verified by stimulation of in vivo Na+/K+-ATPase activity in the presence of the ionophore monensin. In the presence of monensin, in vivo Na+/K+-ATPase activities in embryos of S. purpuratus increased to 94 % of the maximum enzyme activity measured in vitro. Stimulation of in vivo Na+/K+-ATPase activity was also observed in the presence of dissolved alanine, presumably due to the requirement to remove the additional intracellular Na+ that was cotransported with alanine from sea water. The metabolic cost of maintaining the ionic balance was found to be high, with this process alone accounting for 40 % of the metabolic rate of sea urchin larvae (based on the measured fraction of total Na+/K+-ATPase that is physiologically active in larvae of S. purpuratus). Ontogenetic changes in pump activity and environmentally induced regulation of reserve Na+/K+-ATPase activity are important factors that determine a major proportion of the metabolic costs of sea urchin development.

Autogenous regulation of tubulin synthesis via RNA stability during sea urchin embryogenesis

Development ◽  
1988 ◽  
Vol 102 (1) ◽  
pp. 31-43
Author(s):  
Z.Y. Gong ◽  
B. Brandhorst
Keyword(s):  
Rna Stability ◽  
Rapid Decline ◽  
Lytechinus Pictus ◽  
Tubulin Genes ◽  
Low Concentrations ◽  
Rate Of Decay ◽  
Tubulin Mrna ◽  
High Concentrations ◽  
Autogenous Regulation ◽  
Microtubule Stabilizing Agent

When pluteus embryos of Lytechinus pictus were treated with colcemid, the incorporation of [35S]methionine into tubulin declined by 5- to 15-fold within 4 h. This was mostly accounted for by a rapid decline in the concentration of alpha- and beta-tubulin mRNA in the cytoplasm. Treatment with other microtubule depolymerizing agents (colchicine, nocodazole, low concentrations of vinblastine) had similar effects. Treatment of embryos with the microtubule-stabilizing agent, taxol, or high concentrations of vinblastine resulted in increased synthesis of tubulin. The concentration of tubulin mRNA increases during development and becomes increasingly sensitive to colcemid and decreasingly sensitive to taxol. The transcriptional activity of tubulin genes, estimated by an RNA run-on assay in isolated nuclei, was not altered after colcemid treatment. On the other hand, the rate of decay of tubulin mRNA in prism embryos treated with actinomycin D was increased several fold by colcemid treatment, while taxol treatment led to an increased half-life of tubulin mRNA. These observations suggest that tubulin synthesis is autogenously regulated at the level of mRNA stability by the level of unpolymerized tubulin. The increasing polymerization of microtubules and declining level of unpolymerized tubulin during embryogenesis would result in a stabilization of tubulin mRNA accounting for the increasing concentration of tubulin mRNA and rate of tubulin synthesis, as well as the increasing sensitivity of tubulin synthesis to microtubule-depolymerizing agents. Evidence is also presented for a rapid influence of the level of unpolymerized tubulin on the efficiency of translation of tubulin mRNA.

Differential regulation of beta III and other tubulin genes during peripheral and central neuron development

1992 ◽  
Vol 103 (3) ◽  
pp. 643-651
Author(s):  
Y.Q. Jiang ◽  
M.M. Oblinger
Keyword(s):  
Postnatal Development ◽  
Developmental Stages ◽  
Specific Class ◽  
Mrna Levels ◽  
Neuron Development ◽  
Tubulin Gene ◽  
Opposite Pattern ◽  
Peripheral Neurons ◽  
Tubulin Genes ◽  
Tubulin Mrna

Mammalian peripheral and central neurons differ considerably in the composition and properties of their axonal cytoskeletons. Recent reports of the selective expression of a high molecular weight (HMW) tau protein in neurons with peripherally projecting axons have furthered the idea that the microtubules in central and peripheral neurons are disparate. In the present study, we examined the possibility that the various tubulin genes are differentially expressed in central versus peripheral neurons. To examine this, we compared the expression of four of the beta-tubulin mRNAs (classes beta I, beta II, beta III, beta IV) and the alpha 1-tubulin mRNA in rat dorsal root ganglion (DRG) neurons with their expression in cerebral cortex during postnatal development (P5-90), using northern blots and in situ hybridization. We document both similarities and differences in tubulin gene expression in these two regions of the neuraxis during postnatal development. In both DRG and cortex, the expression of the class beta I- and beta II-tubulin mRNAs and the alpha 1-tubulin mRNA was higher at earlier stages of postnatal development than in the adult. However, class beta IV-tubulin mRNA levels increased during cortical development but decreased during DRG postnatal development. The opposite pattern was found for the neuron-specific class beta III-tubulin gene, the mRNA levels of which were high in cortex, at birth and then decreased with increasing postnatal development. In DRG, the beta III-tubulin mRNA levels generally increased during postnatal development. Beta III-tubulin protein levels were examined qualitatively at different developmental stages (5-90 days) by immunoblotting and immunocytochemistry.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals The alpha-tubulin gene family expressed during cell differentiation in Naegleria gruberi.

1988 ◽  
Vol 106 (6) ◽  
pp. 2035-2046 ◽  
Author(s):  
E Y Lai ◽  
S P Remillard ◽  
C Fulton
Keyword(s):  
Gene Family ◽  
Gene Organization ◽  
Cdna Clones ◽  
Tubulin Gene ◽  
Alpha Tubulin ◽  
Tubulin Genes ◽  
Tubulin Mrna ◽  
Protein Conservation ◽  
Naegleria Gruberi

Genes that direct the programmed synthesis of flagellar alpha-tubulin during the differentiation of Naegleria gruberi from amebae to flagellates have been cloned, and found to be novel with respect to gene organization, sequence, and conservation. The flagellar alpha-tubulin gene family is represented in the genome by about eight homologous DNA segments that are exceptionally similar and yet are neither identical nor arrayed in a short tandem repeat. The coding regions of three of these genes have been sequenced, two from cDNA clones and one from an intronless genomic gene. These three genes encode an identical alpha-tubulin that is conserved relative to the alpha-tubulins of other organisms except at the carboxyl terminus, where the protein is elongated by two residues and ends in a terminal glutamine instead of the canonical tyrosine. In spite of the protein conservation, the Naegleria DNA sequence has diverged markedly from the alpha-tubulin genes of other organisms, a counterexample to the idea that tubulin genes are conserved. alpha-Tubulin mRNA homologous to this gene family has not been detected in amebae. This mRNA increases markedly in abundance during the first hour of differentiation, and then decreases even more rapidly with a half-life of approximately 8 min. The abundance of physical alpha-tubulin mRNA rises and subsequently falls in parallel with the abundance of translatable flagellar tubulin mRNA and with the in vivo rate of flagellar tubulin synthesis, which indicates that flagellar tubulin synthesis is directly regulated by the relative rates of transcription and mRNA degradation.

Transcriptional regulation of tubulin gene expression in differentiating trochoblasts during early development of Patella vulgata

Development ◽  
1994 ◽  
Vol 120 (10) ◽  
pp. 2835-2845
Author(s):  
W.G. Damen ◽  
L.A. van Grunsven ◽  
A.E. van Loon
Keyword(s):  
Gene Expression ◽  
Gene Product ◽  
Cell Lines ◽  
Upstream Region ◽  
Tubulin Gene ◽  
Beta Tubulin ◽  
Cell Stage ◽  
Alpha Tubulin ◽  
Tubulin Genes ◽  
Tubulin Mrna

The expression of alpha- and beta-tubulin genes during the early development of the marine mollusk Patella vulgata has been investigated. From the 32-cell stage onwards, an enhanced expression of both alpha- and beta-tubulin mRNAs was detected in the primary trochoblasts. After one additional cleavage, these cells become cleavage-arrested and then form cilia. They are the first cells to differentiate during Patella development. Later, alpha- and beta-tubulin mRNA is also found in the accessory and secondary trochoblasts. Together these three cell-lines form the prototroch, the ciliated locomotory organ of the trochophore larva. The early and abundant expression of tubulin genes precede and accompany cilia formation in the trochoblasts and provides us with an excellent molecular differentiation marker for these cells. Apart from the trochoblasts, tubulin gene expression was also found in other cells at some stages. At the 88-cell stage, elevated tubulin mRNA levels were found around the large nucleus of the mesodermal stem cell 4d. In later stages, tubulin gene expression was detected in the cells that form the flagella of the apical tuft and in the refractive bodies. An alpha-tubulin gene was isolated and characterized. A lacZ fusion gene under control of the 5′ upstream region of this tubulin gene was microinjected into embryos at the two-cell stage. The reporter gene product was only detected in the three trochoblast cell-lines at the same time as tubulin genes were expressed in these cells. Reporter gene product was not detected in any other cells. Thus, this 5′ upstream region of this alpha-tubulin gene contains all the elements required for the correct spatiotemporal pattern of expression.

scholarly journals Gene-specific signal transduction between microtubules and tubulin genes in Tetrahymena thermophila.

1995 ◽  
Vol 15 (9) ◽  
pp. 5173-5179 ◽  
Author(s):  
L Gu ◽  
J Gaertig ◽  
L A Stargell ◽  
M A Gorovsky
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Mammalian Cells ◽  
Tetrahymena Thermophila ◽  
Tubulin Gene ◽  
Beta Tubulin ◽  
Alpha Tubulin ◽  
Tubulin Genes ◽  
Cell Biol ◽  
Tubulin Mrna

Mammalian cells regulate tubulin mRNA abundance by a posttranscriptional mechanism dependent on the concentration of tubulin monomer. Treatment of mammalian cells with microtubule-depolymerizing drugs and microtubule-polymerizing drugs causes decreases and increases in tubulin mRNA, respectively (D. W. Cleveland, Curr. Opin. Cell Biol. 1:10-14, 1989). In striking contrast to the case with mammalian cells, perturbation of microtubules in Tetrahymena thermophila by microtubule-depolymerizing or -polymerizing drugs increases the level of the single alpha-tubulin gene message by increasing transcription (L. A. Stargell, D. P. Heruth, J. Gaertig, and M. A. Gorovsky, Mol. Cell. Biol. 12:1443-1450, 1992). In this report we show that antimicrotubule drugs preferentially induce the expression of one of two beta-tubulin genes (BTU1) in T. thermophila. In contrast, deciliation induces expression of both beta-tubulin genes. Tubulin gene expression was examined in a mutant strain created by transformation with an in vitro-mutagenized beta-tubulin gene that conferred resistance to microtubule-depolymerizing drugs and sensitivity to the polymerizing drug taxol and in a strain containing a nitrosoguanidine-induced mutation in the single alpha-tubulin gene that conferred the same pattern of drug sensitivities. In both cases the levels of tubulin mRNA expression from the drug-inducible BTU1 gene in the mutant cells paralleled the altered growth sensitivities to microtubule drugs. These studies demonstrate that T. thermophila has distinct, gene-specific mechanisms for modulating tubulin gene expression depending on whether ciliary or cytoplasmic microtubules are involved. They also show that the cytoplasmic microtubule cytoskeleton itself participates in a signal transduction pathway that regulates specific tubulin gene transcription in T. thermophila.

Activator protein-1 is necessary for angiotensin-II stimulation of human adrenocorticotropin receptor gene transcription

2001 ◽  
Vol 268 (6) ◽  
pp. 1802-1810
Author(s):  
Danielle Naville ◽  
Estelle Bordet ◽  
Marie-Claude Berthelon ◽  
Philippe Durand ◽  
Martine Begeot
Keyword(s):  
Angiotensin Ii ◽  
Gene Transcription ◽  
Receptor Gene ◽  
Activator Protein 1 ◽  
Activator Protein ◽  
Stimulation Of

Phylogeny of actin and tubulin gene homologs in diverse eukaryotic species

2019 ◽  
Vol 79 (01S) ◽  
Author(s):  
Pawan Kumar Jayaswal ◽  
Asheesh Shanker ◽  
Nagendra Kumar Singh
Keyword(s):  
Evolutionary Relationship ◽  
Genomic Data ◽  
Gene Clusters ◽  
Species Trees ◽  
Model Species ◽  
Tubulin Gene ◽  
Tubulin Genes ◽  
Eukaryotic Species ◽  
Relationship Of ◽  
Insight Into

Actin and tubulin are cytoskeleton proteins, which are important components of the celland are conserved across species. Despite their crucial significance in cell motility and cell division the distribution and phylogeny of actin and tubulin genes across taxa is poorly understood. Here we used publicly available genomic data of 49 model species of plants, animals, fungi and Protista for further understanding the distribution of these genes among diverse eukaryotic species using rice as reference. The highest numbers of rice actin and tubulin gene homologs were present in plants followed by animals, fungi and Protista species, whereas ten actin and nine tubulin genes were conserved in all 49 species. Phylogenetic analysis of 19 actin and 18 tubulin genes clustered them into four major groups each. One each of the actin and tubulin gene clusters was conserved across eukaryotic species. Species trees based on the conserved actin and tubulin genes showed evolutionary relationship of 49 different taxa clustered into plants, animals, fungi and Protista. This study provides a phylogenetic insight into the evolution of actin and tubulin genes in diverse eukaryotic species.

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