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31.
Kachhap SK Faith D Qian DZ Shabbeer S Galloway NL Pili R Denmeade SR DeMarzo AM Carducci MA 《PloS one》2007,2(9):e844
Cell to cell adhesion is mediated by adhesion molecules present on the cell surface. Downregulation of molecules that form the adhesion complex is a characteristic of metastatic cancer cells. Downregulation of the N-myc down regulated gene1 (NDRG1) increases prostate and breast metastasis. The exact function of NDRG1 is not known. Here by using live cell confocal microscopy and in vitro reconstitution, we report that NDRG1 is involved in recycling the adhesion molecule E-cadherin thereby stabilizing it. Evidence is provided that NDRG1 recruits on recycling endosomes in the Trans Golgi network by binding to phosphotidylinositol 4-phosphate and interacts with membrane bound Rab4aGTPase. NDRG1 specifically interacts with constitutively active Rab4aQ67L mutant protein and not with GDP-bound Rab4aS22N mutant proving NDRG1 as a novel Rab4a effector. Transferrin recycling experiments reveals NDRG1 colocalizes with transferrin during the recycling phase. NDRG1 alters the kinetics of transferrin recycling in cells. NDRG1 knockdown cells show a delay in recycling transferrin, conversely NDRG1 overexpressing cells reveal an increase in rate of transferrin recycling. This novel finding of NDRG1 as a recycling protein involved with recycling of E-cadherin will aid in understanding NDRG1 role as a metastasis suppressor protein. 相似文献
32.
33.
Lapierre LA Dorn MC Zimmerman CF Navarre J Burnette JO Goldenring JR 《Experimental cell research》2003,290(2):322-331
The Rab11 family of small GTPases is composed of three members, Rab11a, Rab11b, and Rab25. While recent work on Rab11a and Rab25 has yielded some insights into their function, Rab11b has received little attention. Therefore, we sought to examine the distribution of endogenous Rab11b in epithelial cells. In rabbit gastric parietal cells, unlike Rab11a, Rab11b did not colocalize or coisolate with H(+)/K(+)-ATPase. In MDCK cells, endogenous Rab11b localized to an apical pericentrisomal region distinct from Rab11a. The microtubule agents nocodazole and taxol dramatically alter Rab11a's localization in the cell, while effects on Rab11b's distribution were less apparent. These results indicate that in contrast to Rab11a, the Rab11b compartment in the apical region is not as dependent upon microtubules. While Rab11a is known to regulate transferrin trafficking in nonpolarized cells and IgA trafficking in polarized cells, Rab11b exhibited little colocalization with either of these cargoes. Thus, while Rab11a and Rab11b share high sequence homology, they appear to reside within distinct vesicle compartments. 相似文献
34.
We suggest applying the log-periodic law formerly used to describe various crisis phenomena, in biology (evolutionary leaps), inorganic systems (earthquakes), societies and economy (economic crisis, market crashes) to the various steps of human ontogeny. We find a statistically significant agreement between this model and the data. 相似文献
35.
Myles S Faith Kathleen L Keller Patty Matz Susan L Johnson Rebecca Lewis Marie Alexandra Jorge Clare Ridley Helen Han Shoshanna Must Moonseong Heo Angelo Pietrobelli Steven B Heymsfield David B Allison 《Twin research》2002,5(5):472-475
"Project Grow-2-Gether" is a child nutrition study of same-sex, 3- to 7-year-old monozygotic and dizygotic twin pairs. The study attempts to bridge two bodies of literature that have rarely interfaced with respect to obesity and ingestive behavior: the first being behavioral genetic approaches to obesity-related traits, and the second being developmental approaches focusing on parent-child relationships. The overarching aim of Project Grow-2-Gether is to disentangle genetic from potential home-environmental influences on child eating behavior and body fat. This paper reviews the rationale for Project Grow-2-Gether, its procedures, and core phenotypic measurement battery. A focus of the study is acquisition of controlled food intake measurements obtained in the laboratory, measurement of specific home environmental variables, and multi-method evaluation of parent-child feeding relations. Future directions may involve longitudinal assessment of child growth and molecular analyses for specific genes that influence child eating behavior. 相似文献
36.
Markaverich BM Alejandro MA Markaverich D Zitzow L Casajuna N Camarao N Hill J Bhirdo K Faith R Turk J Crowley JR 《Biochemical and biophysical research communications》2002,291(3):692-700
A mitogenic agent in corncob bedding and fresh corn products disrupts sexual behavior and estrous cyclicity in rats. The mitogenic activity resides in an isomeric mixture of linoleic acid derivatives with a tetrahydrofuran ring and two hydroxyl groups (THF-diols) that include 9, (12)-oxy-10,13-dihydroxystearic acid and 10, (13)-oxy-9,12-dihydroxystearic acid. Synthetic THF-diols stimulated breast cancer cell proliferation in vitro and disrupted the estrous cycle in female rats at oral doses of approximately 0.30 mg/kg body weight/day. Exposure to THF-diols may disrupt endocrine function in experimental animals at doses approximately 200 times lower than classical phytoestrogens, promote proliferation of breast or prostate cancer, and adversely affect human health. 相似文献
37.
Joseph M. Culp Cheryl L. Podemski Kevin J. Cash Richard B. Lowell 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》2000,7(4):359-360
Authors Index
Author Index, Volume 7 相似文献38.
Effects of three different handling aids on calf behavior were determined. Group 1 calves were intensively-reared intact Holstein males (mean 180 days old); Group 2, extensively-reared beef-breed females (mean 230 days); Group 3, extensively-reared castrated beef-breed males (mean 253 days). Calves in each group were assigned to one of three handling aid treatments (n=5 per treatment subgroup; total n=45): electric prod (Prod), oar with rattles (Oar), manual urging (Manual). Treatments were applied only as needed to encourage forward movement of calves through the length of a solid-sided semicircular chute system. Number of treatment applications, length of time required to move through the entire chute system, and behavior during movement through the chute were recorded. An approach test was conducted 1 day before and 1 day and 1 week after chute tests to evaluate changes in behavior due to handling aid application. During chute tests, Group 1 Prod calves required the fewest treatment applications (4.9) vs. 23.5 (Oar) or 13.5 (Manual), ran most often (1.40 times) vs. 0.20 times (Manual) or 0.33 times (Oar), and made contact with chute sides most often (1.8 times vs. 0.2 times (Manual) or 0.7 times (Oar), respectively (all P<0.05). Similar trends were observed for calves in Groups 2 and 3. There were no significant differences between behaviors observed during the approach tests conducted before and after handling aid treatments had been imposed. Regardless of treatment, intensively-reared Group 1 calves appeared markedly less fearful of handlers during approach tests compared to extensively-reared calves in Groups 2 and 3, which demonstrated overt attempts to escape from the test facilities. One week after chute tests, 13 of 15 Prod calves from all three groups walked, rushed, or backed >1 m away from the handler when the prod was buzzed but not applied, suggesting that the buzzing sound alone may have sufficed to encourage movement by calves that had previously experienced both the sensation and sound associated with electric prodding. 相似文献
39.
Proteomic changes in the brain of the western painted turtle (Chrysemys picta bellii) during exposure to anoxia 下载免费PDF全文
During anoxia, overall protein synthesis is almost undetectable in the brain of the western painted turtle. The aim of this investigation was to address the question of whether there are alterations to specific proteins by comparing the normoxic and anoxic brain proteomes. Reductions in creatine kinase, hexokinase, glyceraldehyde‐3‐phosphate dehydrogenase, and pyruvate kinase reflected the reduced production of adenosine triphosphate (ATP) during anoxia while the reduction in transitional endoplasmic reticulum ATPase reflected the conservation of ATP or possibly a decrease in intracellular Ca2+. In terms of neural protection programed cell death 6 interacting protein (PDCD6IP; a protein associated with apoptosis), dihydropyrimidinase‐like protein, t‐complex protein, and guanine nucleotide protein G(o) subunit alpha (Go alpha; proteins associated with neural degradation and impaired cognitive function) also declined. A decline in actin, gelsolin, and PDCD6IP, together with an increase in tubulin, also provided evidence for the induction of a neurological repair response. Although these proteomic alterations show some similarities with the crucian carp (another anoxia‐tolerant species), there are species‐specific responses, which supports the theory of no single strategy for anoxia tolerance. These findings also suggest the anoxic turtle brain could be an etiological model for investigating mammalian hypoxic damage and clinical neurological disorders. 相似文献
40.
Timothy Abuya Charlotte E. Warren Nora Miller Rebecca Njuki Charity Ndwiga Alice Maranga Faith Mbehero Anne Njeru Ben Bellows 《PloS one》2015,10(4)