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Farnesylated Lamins, Progeroid Syndromes And Farnesyl Transferase Inhibitors, Michael Sinensky, A. E. Rusinol
Farnesylated Lamins, Progeroid Syndromes And Farnesyl Transferase Inhibitors, Michael Sinensky, A. E. Rusinol
Michael Sinensky
Three mammalian nuclear lamin proteins, lamin B1, lamin B2 and the lamin A precursor, prelamin A, undergo canonical farnesylation and processing at CAAX motifs. In the case of prelamin A, there is an additional farnesylation-dependent endoproteolysis, which is defective in two congenital diseases: Hutchinson-Gilford progeria (HGPS) and restrictive dermopathy (RD). These two diseases arise respectively from defects in the prelamin A substrate and the enzyme (ZmpSte24) that processes it. Recent work has shed light on the roles of the lamin proteins and the enzymes involved in their farnesylation-dependent maturation. Other experimental work, including mouse model studies, have examined the possibility …
Dna Damage Responses In Progeroid Syndromes Arise From Defective Maturation Of Prelamin A, Michael Sinensky, Y. Liu, A. Rusinol, Y. Wang, Y. Zou
Dna Damage Responses In Progeroid Syndromes Arise From Defective Maturation Of Prelamin A, Michael Sinensky, Y. Liu, A. Rusinol, Y. Wang, Y. Zou
Michael Sinensky
The genetic diseases Hutchinson-Gilford progeria syndrome (HGPS) and restrictive dermopathy (RD) arise from accumulation of farnesylated prelamin A because of defects in the lamin A maturation pathway. Both of these diseases exhibit symptoms that can be viewed as accelerated aging. The mechanism by which accumulation of farnesylated prelamin A leads to these accelerated aging phenotypes is not understood. Here we present evidence that in HGPS and RD fibroblasts, DNA damage checkpoints are persistently activated because of the compromise in genomic integrity. Inactivation of checkpoint kinases Ataxia-telangiectasia-mutated (ATM) and ATR (ATM- and Rad3-related) in these patient cells can partially overcome their …
Interpolation Of Tracking Data In A Fluid Environment, Y Tremblay, Scott A. Shaffer, S L. Fowler, C E. Kuhn, B I. Mcdonald, M J. Weise, C -A Bost, H Weimerskirch, D E. Crocker, M E. Goebel, D P. Costa
Interpolation Of Tracking Data In A Fluid Environment, Y Tremblay, Scott A. Shaffer, S L. Fowler, C E. Kuhn, B I. Mcdonald, M J. Weise, C -A Bost, H Weimerskirch, D E. Crocker, M E. Goebel, D P. Costa
Scott A. Shaffer
Interpolation of geolocation or Argos tracking data is a necessity for habitat use analyses of marine vertebrates. In a fluid marine environment, characterized by curvilinear structures, linearly interpolated track data are not realistic. Based on these two facts, we interpolated tracking data from albatrosses, penguins, boobies, sea lions, fur seals and elephant seals using six mathematical algorithms. Given their popularity in mathematical computing, we chose Bézier, hermite and cubic splines, in addition to a commonly used linear algorithm to interpolate data. Performance of interpolation methods was compared with different temporal resolutions representative of the less-precise geolocation and the more-precise Argos …
Slate-Throated Redstarts (Myioborus Miniatus) Breeding In Maderas Del Carmen, Coahuila, Mexico, John Mccormack
Slate-Throated Redstarts (Myioborus Miniatus) Breeding In Maderas Del Carmen, Coahuila, Mexico, John Mccormack
John E. McCormack
The breeding range of the slate-throated redstart (Myioborus miniatus) stretches from South America to Mexico, where it extends northward along the Sierra Madre Oriental to southeastern Coahuila and along the Sierra Madre Occidental to southern Chihuahua and Sonora. We report the discovery of slate-throated redstarts breeding in the Maderas del Carmen mountains in Coahuila. This represents a range extension of approximately 400 km and is, to our knowledge, the northernmost breeding record for this species.
Reduced Macrophage Apoptosis Is Associated With Accelerated Atherosclerosis In Low-Denstiy Lipoprotein Receptor-Null Mice, Michael Sinensky, J. Liu, D. P. Thweke, Y. R. Su, M. F. Linton, S. Fazio
Reduced Macrophage Apoptosis Is Associated With Accelerated Atherosclerosis In Low-Denstiy Lipoprotein Receptor-Null Mice, Michael Sinensky, J. Liu, D. P. Thweke, Y. R. Su, M. F. Linton, S. Fazio
Michael Sinensky
Objective— The majority of apoptotic cells in atherosclerotic lesions are macrophages. However, the pathogenic role of macrophage apoptosis in the development of atherosclerosis remains unclear. Elevated expression of Bax, one of the pivotal proapoptotic proteins of the Bcl-2 family, has been found in human atherosclerotic plaques. Activation of Bax also occurs in free cholesterol-loaded and oxysterol-treated mouse macrophages. In this study, we examined the effect of Bax deficiency in bone marrow-derived leukocytes on the development of atherosclerosis in low-density lipoprotein receptor-null (LDLR−/−) mice. Methods and Results— Fourteen 8-week-old male LDLR−/− mice were lethally irradiated and reconstituted with either wild-type (WT) …
An Evaluation Of The Potential Of Atriplex Nummualria For Sheep Production In Arid Jordanian Rangelands, Raed Al-Tabini, A. Younger
An Evaluation Of The Potential Of Atriplex Nummualria For Sheep Production In Arid Jordanian Rangelands, Raed Al-Tabini, A. Younger
Raed Al-Tabini
No abstract provided.
The Comparative Energetics And Growth Strategies Of Sympatric Antarctic And Sub Antarctic Fur Seal Pups, At Iles Crozet, J Py Arnould, S P. Luque, C Guinet, D P. Costa, J Kingston, Scott A. Shaffer
The Comparative Energetics And Growth Strategies Of Sympatric Antarctic And Sub Antarctic Fur Seal Pups, At Iles Crozet, J Py Arnould, S P. Luque, C Guinet, D P. Costa, J Kingston, Scott A. Shaffer
Scott A. Shaffer
The period of maternal dependence is a time during which mammalian infants must optimise both their growth and the development of behavioural skills in order to successfully meet the demands of independent living. The rate and duration of maternal provisioning, post-weaning food availability and climatic conditions are all factors likely to influence the growth strategies of infants. While numerous studies have documented differences in growth strategies at high taxonomic levels, few have investigated those of closely related species inhabiting similar environments. The present study examined the body composition, metabolism and indices of physiological development in pups of Antarctic fur seals …
Heart Rate And Energy Expenditure Of Incubating Wandering Albatrosses: Basal Levels, Natural Variation, And The Effects Of Human Disturbance, H Weimerskirch, Scott A. Shaffer, G Mabille, J Martin, O Boutard, J-L Rouanet
Heart Rate And Energy Expenditure Of Incubating Wandering Albatrosses: Basal Levels, Natural Variation, And The Effects Of Human Disturbance, H Weimerskirch, Scott A. Shaffer, G Mabille, J Martin, O Boutard, J-L Rouanet
Scott A. Shaffer
We studied the changes in heart rate (HR) associated with metabolic rate of incubating and resting adult wandering albatrosses (Diomedea exulans) on the Crozet Islands. Metabolic rates of resting albatrosses fitted with external HR recorders were measured in a metabolic chamber to calibrate the relationship between HR and oxygen consumption (V̇O2) (V̇O2=0.074×HR+0.019, r2=0.567, P<0.001, where V̇O2 is in ml kg–1 min–1 and HR is in beats min–1). Incubating albatrosses were then fitted with HR recorders to estimate energy expenditure of albatrosses within natural field conditions. We also examined the natural variation in HR and the effects of human disturbance on nesting birds by monitoring the changes in HR. Basal HR was positively related to the mass of the individual. The HR of incubating birds corresponded to a metabolic rate that was 1.5-fold (males) and 1.8-fold (females) lower than basal metabolic rate (BMR) measured in this and a previous study. The difference was probably attributable to birds being stressed while they were held in the metabolic chamber or wearing a mask. Thus, previous measurements of metabolic rate under basal conditions or for incubating wandering albatrosses are likely to be overestimates. Combining the relationship between HR and metabolic rate for both sexes, we estimate that wandering albatrosses expend 147 kJ kg–1 day–1 to incubate their eggs. In addition, the cost of incubation was assumed to vary because (i) HR was higher during the day than at night, and (ii) there was an effect of wind chill (<0°C) on basal HR. The presence of humans in the vicinity of the nest or after a band control was shown to increase HR for extended periods (2–3 h), suggesting that energy expenditure was increased as a result of the disturbance. Lastly, males and females reacted differently to handling in terms of HR response: males reacted more strongly than females before handling, whereas females took longer to recover after being handled.
Browsing Behaviour Of Awassi Ewes On Atriplex Nummularia, Raed Al-Tabini, A. Younger
Browsing Behaviour Of Awassi Ewes On Atriplex Nummularia, Raed Al-Tabini, A. Younger
Raed Al-Tabini
No abstract provided.
A Comparison Of Methods To Evaluate Energy Expenditure Of Incubating Wandering Albatrosses, Scott A. Shaffer, D P. Costa, H Weimerskirch
A Comparison Of Methods To Evaluate Energy Expenditure Of Incubating Wandering Albatrosses, Scott A. Shaffer, D P. Costa, H Weimerskirch
Scott A. Shaffer
Measurements of incubation energetics can vary depending on the method used to measure metabolism of an incubating bird. Therefore, we evaluated the energy expenditure of six male and four female wandering albatrosses (Diomedea exulans Linnaeus) using doubly labeled water (DLW), the rate of mass loss, and estimates of metabolic water production derived from water influx rate (WIR). Incubation metabolic rates (IMR) determined with DLW ( 169 ± 21 kJ kg d SD) were significantly lower than estimates derived from mass loss ( 277 ± 46kJ kg d SD) and WIR ( males=289 ± 60 kJ kg d vs. females = …
Precise, Highly Female-Biased Sex Ratios In A Social Spider, Leticia Avilés, John Mccormack, Asher Cutter, Todd Bukowski
Precise, Highly Female-Biased Sex Ratios In A Social Spider, Leticia Avilés, John Mccormack, Asher Cutter, Todd Bukowski
John E. McCormack
It has been recognized for some time that the risk of producing maleless clutches should select for a lower than binomial variance in the sex ratio of organisms with female–biased sex ratios, small clutches and breeding groups containing the clutch of a single female. However, to date, precise sex ratios have only been reported for organisms with haplodiploid sex determination, a system which allows direct control of the sex of individual offspring. In contrast, under heterogametic sex determination chance is expected to play a crucial role in determining the sex composition of any one family, in particular when males are …
Wool Production And Marketing, Raed Al-Tabini
The Nature And Significant Of Livestock Trading In The North – East Badia Of Jordan, Raed Al-Tabini, R. Oakley
The Nature And Significant Of Livestock Trading In The North – East Badia Of Jordan, Raed Al-Tabini, R. Oakley
Raed Al-Tabini
No abstract provided.
Chi Gong--An Exercise For Internal Health, G. Chen, Shirley H. M. Reekie
Chi Gong--An Exercise For Internal Health, G. Chen, Shirley H. M. Reekie
Shirley H. M. Reekie
No abstract provided.
Expression Of Prelamin A Confers Sensitivity Of Dna Biosynthesis To Lovastatin On F9 Teratocarcinoma Cells, Michael Sinensky, T. Mclain, K. Fantle
Expression Of Prelamin A Confers Sensitivity Of Dna Biosynthesis To Lovastatin On F9 Teratocarcinoma Cells, Michael Sinensky, T. Mclain, K. Fantle
Michael Sinensky
No abstract provided.
The Processing Pathway Of Prelamin A, Michael Sinensky, K. Fantle, M. Trujillo, T. Mclain, A. Kupfer, M. Dalton
The Processing Pathway Of Prelamin A, Michael Sinensky, K. Fantle, M. Trujillo, T. Mclain, A. Kupfer, M. Dalton
Michael Sinensky
The conversion of mammalian prelamin A to mature lamin A proceeds through the removal of 18 amino acids from the carboxyl terminus. The initial step in this processing is the isoprenylation of a CAAX box cysteine. This proteolytic event is distinctive for prelamin A among the known prenylated mammalian proteins. Since the carboxyl terminus of prelamin A is removed during maturation, it is not obvious that this protein would undergo the two reactions subsequent to prenylation observed in other CAAX box proteins-the endoproteolytic removal of the carboxyl-terminal 3 amino acids and the subsequent methylation of the now carboxyl-terminal cysteine. To …
Rounding Buoys Quickly And Cleanly, Shirley H. M. Reekie
Rounding Buoys Quickly And Cleanly, Shirley H. M. Reekie
Shirley H. M. Reekie
No abstract provided.
Physical Education And Social Studies: The Natural Alliance, C. M. Buell, Shirley H. M. Reekie
Physical Education And Social Studies: The Natural Alliance, C. M. Buell, Shirley H. M. Reekie
Shirley H. M. Reekie
No abstract provided.
Isoprenylation Is Required For The Processing Of The Lamin A Precursor, Michael Sinensky, L. A. Beck, T. J. Hosick
Isoprenylation Is Required For The Processing Of The Lamin A Precursor, Michael Sinensky, L. A. Beck, T. J. Hosick
Michael Sinensky
The nuclear lamina proteins, prelamin A, lamin B, and a 70-kD lamina-associated protein, are posttranslationally modified by a metabolite derived from mevalonate. This modification can be inhibited by treatment with (3-R,S)-3-fluoromevalonate, demonstrating that it is isoprenoid in nature. We have examined the association between isoprenoid metabolism and processing of the lamin A precursor in human and hamster cells. Inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase by mevinolin (lovastatin) specifically depletes endogenous isoprenoid pools and inhibits the conversion of prelamin A to lamin A. Prelamin A processing is also blocked by mevalonate starvation of Mev-1, a CHO cell line auxotrophic for mevalonate. …
Resistance-Training Techniques, L Kravitz, C J. Cisar
Resistance-Training Techniques, L Kravitz, C J. Cisar
Craig J. Cisar
No abstract provided.
Man Overboard Maneuvers, Shirley H. M. Reekie
Man Overboard Maneuvers, Shirley H. M. Reekie
Shirley H. M. Reekie
No abstract provided.
Capsizing: How To Prevent It/How To Recover From It, Shirley H. M. Reekie
Capsizing: How To Prevent It/How To Recover From It, Shirley H. M. Reekie
Shirley H. M. Reekie
No abstract provided.
Incorporation Of A Product Of Mevalonic Acid Metabolism Into Proteins Of Chinese Hamster Ovary Nuclei, Michael Sinensky, L. A. Beck, T. Hosick
Incorporation Of A Product Of Mevalonic Acid Metabolism Into Proteins Of Chinese Hamster Ovary Nuclei, Michael Sinensky, L. A. Beck, T. Hosick
Michael Sinensky
We have examined the nuclear localization of isoprenylated proteins in CHO-K1 cells labeled with [14C]mevalonate. Nuclear proteins of 68, 70, and 74 kD, posttranslationally modified by an isoprenoid, are also components of a nuclear matrix-intermediate filament preparation from CHO cells. Furthermore, the 68-, 70-, and 74-kD isoprenylated polypeptides are immunoprecipitated from cell extracts with two different anti-lamin antisera. Based on exact two-dimensional comigration with lamin B, both from rat liver lamin and CHO nuclear matrix-intermediate filament preparations, and its immunoprecipitation with anti-lamin antisera, we conclude that the 68-kD isoprenylated protein found in nuclei from [14C]mevalonate-labeled CHO cells is lamin B. …
Great Gains Or Weight Work, L Kravitz, C J. Cisar
Great Gains Or Weight Work, L Kravitz, C J. Cisar
Craig J. Cisar
No abstract provided.
Estimation Of Body Density In Adolescent Athletes, W G. Thorland, G O. Johnson, G D. Tharp, T J. Housh, C J. Cisar
Estimation Of Body Density In Adolescent Athletes, W G. Thorland, G O. Johnson, G D. Tharp, T J. Housh, C J. Cisar
Craig J. Cisar
National samples of 141 male and 133 female highly-trained adolescent athletes were studied to derive anthropometric-based equations predicting body density. Anthropometric measures included skinfold thicknesses at seven sites, circum- ferences at 14 sites, and diameters at nine sites. Criterion measures of body density were determined by underwater weighing with corrections for residual lung vol- ume based on the oxygen dilution method. Variable selection procedures included factor analysis followed by forward-stepping regression and polynomial analysis. For both the male and female samples, two quadratic equations utilizing either the sum of three or seven skinfold measures were derived. Within the male sample, …
Comparative Physical Education And Sport In Real Life, Shirley H. M. Reekie
Comparative Physical Education And Sport In Real Life, Shirley H. M. Reekie
Shirley H. M. Reekie
No abstract provided.
Youth Sports In England, Shirley H. M. Reekie
Youth Sports In England, Shirley H. M. Reekie
Shirley H. M. Reekie
No abstract provided.
Adaptative Alteration In Phospholipid Composition Of Plasma Membranes From A Somatic Cell Mutant Defective In The Regulation Of Cholesterol Biosynthesis, Michael Sinensky
Adaptative Alteration In Phospholipid Composition Of Plasma Membranes From A Somatic Cell Mutant Defective In The Regulation Of Cholesterol Biosynthesis, Michael Sinensky
Michael Sinensky
A somatic cell mutant (CR1) of a Chinese hamster ovary cell (CHO-K1) which has previously been shown to be defective in the regulation of cholesterol biosynthesis accumulates more cholesterol than the parental cell line in plasma membranes. Although such an increase in membrane cholesterol should lead to an increase in the order parameter of these membranes, as measured with an electron spin resonance spin probe, the order parameters of mutant and wild-type plasma membranes are identical--apparently because of an adaptive alteration in membrane phospholipid composition. The phospholipid compositions of mutant and wild-type cell plasma membranes are compared and the mutant …