Abstract:
:Biochemical studies using highly condensed Xenopus sperm chromatin and protein extracts prepared from multiple systems have lead to the identification of conserved proteins involved in chromosome decondensation. However, mutations to these proteins are unavailable as the systems used are not amenable to genetic studies. We took a genetic approach to isolating chromosome decondensation mutants by incubating Xenopus sperm chromatin with whole-cell extracts prepared from the Hartwell library of random temperature sensitive (ts) yeast cells. We show that decondensation of Xenopus sperm chromatin using wild type yeast extracts was rapid, ATP- and extract-dependent, and resistant to heat, N-ethylmaleimide, protease K, RNase A, and micrococcal nuclease. From 100 mutant extracts screened, we obtained one strain, referred to as rmc4, that was chromosome decondensation defective. The mutant was slow growing and exhibited germination defects. Low concentrations of rmc4 extract would eventually decondense sperm heads, and fractionation of the mutant extract produced a decondensation competent fraction, suggesting the presence of an overactive inhibitor in rmc4 cells. We performed a multicopy suppressor screen that identified PDE2, a gene encoding a protein that inhibits protein kinase A (PKA) activity. As PKA was previously shown in human cells to maintain condensed chromatin, our results suggest that PKA activity is elevated in rmc4 cells, causing a decondensation defect. Thus, our experiments reveal that yeast encodes an evolutionarily conserved chromosome decondensation activity that can be genetically manipulated.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Harkness TAdoi
10.1139/y05-042subject
Has Abstractpub_date
2006-03-01 00:00:00pages
451-8issue
3-4eissn
0008-4212issn
1205-7541pii
y05-042journal_volume
84pub_type
杂志文章abstract::In the mesenteric circulation of the rat a myogenic autoregulatory system operates at 0.1-0.15 Hz. Negative admittance phase in the region above 0.2 Hz suggested operation of an arterial baroreflex. The present study was designed to test this interpretation and to identify the neurotransmitter involved. In rats anesth...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-78-1-54
更新日期:2000-01-01 00:00:00
abstract::When isolated rat adipocytes were incubated with increasing concentrations of levamisole (0.5-5 mM), basal glucose oxidation decreased by almost 50% and insulin-stimulated glucose oxidation decreased by 90%. The decrease in glucose oxidation correlated with an inhibition of glucose transport, since levamisole at 5.0 m...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-165
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-187
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y94-001
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1996-11-01 00:00:00
abstract::The long noncoding RNA (lncRNA) GAS5 has been found to act as a decoy for the glucocorticoid receptor (GR), thus implicating GAS5 as a potential regulator of glucocorticoid sensitivity and resistance. Airway smooth muscle (ASM) cells and airway epithelial cells (AEC) play an important role in the pathogenesis and pers...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2014-0391
更新日期:2015-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-76-5-539
更新日期:1998-05-01 00:00:00
abstract::We compared the determinants of spontaneous activity in explanted neonatal (2-day-old) rat ventricle cells and in reaggregates derived from 15-day-old chick embryos. We studied the beating rate with an optical recording method and the underlying electrical activity with glass microelectrodes using the K current blocke...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-126
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y08-090
更新日期:2008-11-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
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更新日期:1995-01-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-215
更新日期:1980-12-01 00:00:00
abstract::Resting membrane potentials and membrane conductances of chick skeletal muscle in culture were determined from the 3rd to the 10th day after plating. The effect of tetraethylammonium (TEA) and of replacement of potassium with caesium on these parameters was investigated. Resting membrane potential (Em) rises during my...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-100
更新日期:1980-06-01 00:00:00
abstract::Kinins are the endogenous ligands of the constitutive B2 receptor (B2R) and the inducible B1 receptor (B1R). Whereas B2R prevents insulin resistance, B1R is involved in insulin resistance and metabolic syndrome. However, the contribution of B1R in type 2 diabetes associated with obesity remains uncertain. The aim of t...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2016-0063
更新日期:2016-07-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2014-0009
更新日期:2014-08-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y75-020
更新日期:1975-02-01 00:00:00
abstract::The disruption to glucose homeostasis upon glucocorticoid (GC) treatment in adult male rats has not been fully characterized in older rats or in females. Thus, we evaluated the age- and gender-related changes in glucose homeostasis in GC-treated rats. We injected male and female rats at 3 months and 12 months of age w...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2014-0259
更新日期:2014-10-01 00:00:00
abstract::Transactivation of epidermal growth factor receptor (EGFR) is a well-documented mechanism by which vasoactive peptides and H2O2 elicit their cellular responses. However, a role for the insulin-like growth factor type-1 receptor (IGF-1R) transactivation in mediating the effects of angiotensin II (Ang II) and H2O2 in va...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/Y06-101
更新日期:2007-01-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-76-5-469
更新日期:1998-05-01 00:00:00
abstract::The kinetics of sodium gradient dependent phosphate uptake by the renal brush border membrane vesicles of the rat have ben studied under various conditions of temperature and pH. From 7 to 30 degrees C the Lineweaver-Burk plots are linear, and the apparent Km progressively increases from 54 to 91 microM. Above 30 degr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-034
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-107
更新日期:1989-06-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y95-116
更新日期:1995-07-01 00:00:00
abstract::In the present study we have compared the effect of intravenous infusion of a calcium channel blocker, nifedipine (1.0 micrograms.kg-1.min-1 for 20 min), with that of isoproterenol (0.1 micrograms.kg-1.min-1 for 20 min) on the hemodynamic parameters and the vascular response of different locations and tissue layers of...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-238
更新日期:1990-12-01 00:00:00
abstract::Rats fed a polychlorinated biphenyl (PCB) mixture in a high- or low-iodine diet (HID or LID respectively) for 15 days had thyroid enlargement, low serum thyroxine (T4), and high serum thyrotropin concentrations. Although binding of thyroid hormones to serum proteins was reduced in PCB-fed animals, the free T4 index (r...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y77-041
更新日期:1977-04-01 00:00:00
abstract::The responses of the circular muscle of canine colon to stimulation of intrinsic nerves and to the probable mediators of these nerves were studied in vivo. In vivo studies were carried out using close intra-arterial injections and local field stimulation of proximal, mid-, and distal colon while recording circumferent...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y88-060
更新日期:1988-04-01 00:00:00
abstract::To determine the effects of chronic hyperinsulinemia on glucagon release, rats were made hyperinsulinemic for 14 days by supplementation of drinking water with sucrose (10%; sucrose-fed) to increase endogenous release or by implantation of osmotic minipumps (subcutaneous, s.c.; or intraperitoneal, i.p.) to deliver exo...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y91-066
更新日期:1991-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y77-138
更新日期:1977-10-01 00:00:00
abstract::Thymic stromal lymphopoietin (TSLP) was reported to induce mast cell proliferation and aggravate allergic reactions through activation of mouse double minute 2 (MDM2). We aimed to ascertain that β-sitosterol (SI), which is one of the several phytosterols found mostly in foods, would regulate TSLP-induced mast cell pro...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2015-0166
更新日期:2015-11-01 00:00:00
abstract::The effect of adrenaline on the membrane transport of 3-methylglucose was studied in perifused isolated rat left atria that had been fully arrested. In this preparation a high concentration of adrenaline stimulated and a low one decreased sugar transport. The stimulatory effect was strongly inhibited by the beta-adren...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y76-099
更新日期:1976-10-01 00:00:00