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181.
La Rocca G Shi B Audia A Ferrari-Amorotti G Mellert HS Calabretta B McMahon SB Sepp-Lorenzino L Baserga R 《Experimental cell research》2011,(4):488-495
MicroRNA145 (miR145), a tumor suppressor miR, has been reported to inhibit growth of human cancer cells, to induce differentiation and to cause apoptosis, all conditions that result in growth arrest. In order to clarify the functional effects of miR145, we have investigated its expression in diverse conditions and different cell lines. Our results show that miR145 levels definitely increase in differentiating cells and also in growth-arrested cells, even in the absence of differentiation. Increased expression during differentiation sometimes occurs as a late event, suggesting that miR145 could be required either early or late during the differentiation process. 相似文献
182.
183.
McPherson JP Tamblyn L Elia A Migon E Shehabeldin A Matysiak-Zablocki E Lemmers B Salmena L Hakem A Fish J Kassam F Squire J Bruneau BG Hande MP Hakem R 《The EMBO journal》2004,23(18):3677-3688
The Drosophila melanogaster warts/lats tumour suppressor has two mammalian counterparts LATS1/Warts-1 and LATS2/Kpm. Here, we show that mammalian Lats orthologues exhibit distinct expression profiles according to germ cell layer origin. Lats2(-/-) embryos show overgrowth in restricted tissues of mesodermal lineage; however, lethality ultimately ensues on or before embryonic day 12.5 preceded by defective proliferation. Lats2(-/-) mouse embryonic fibroblasts (MEFs) acquire growth advantages and display a profound defect in contact inhibition of growth, yet exhibit defective cytokinesis. Lats2(-/-) embryos and MEFs display centrosome amplification and genomic instability. Lats2 localizes to centrosomes and overexpression of Lats2 suppresses centrosome overduplication induced in wild-type MEFs and reverses centrosome amplification inherent in Lats2(-/-) MEFs. These findings indicate an essential role of Lats2 in the integrity of processes that govern centrosome duplication, maintenance of mitotic fidelity and genomic stability. 相似文献
184.
The equilibria of oxygen binding to and kinetics of CO combination with the symmetrical iron-zinc hybrids of a series of variants of human adult hemoglobin A have been measured at pH 7 in the presence of inositol hexaphosphate (IHP). In addition, the kinetics of CO combination have also been measured in the absence of IHP. The hybrids have the heme groups of either the alpha or the beta subunits replaced by zinc protoporphyrin IX, which is unable to bind a ligand and is a good model for permanently deoxygenated heme. The variants examined involve residues located in the alpha1beta2 interface of the hemoglobin tetramer. Alterations of residues located in the hinge region of the interface are found to affect the properties of both the alpha and the beta subunits of the protein. In contrast, alterations of residues in the switch region of the interface have substantial effects only on the mutant subunit and are poorly communicated to the normal partner subunit. When the logarithms of the rate constants for the combination of the first CO molecule with a single subunit in the presence of IHP are analyzed as functions of the logarithms of the dissociation equilibrium constants for the binding of the first oxygen under the same conditions, a linear relationship is found. The relationship is somewhat different for the alpha and beta subunits, consistent with the well-known differences in the geometries of their ligand binding sites. 相似文献
185.
Xiujuan Li Laura Gualandi Sina Koch Malin Jarvius Ola Söderberg Andrey Anisimov Bronislaw Pytowski Megan Baldwin Seppo Ylä‐Herttuala Kari Alitalo Johan Kreuger Lena Claesson‐Welsh 《The EMBO journal》2010,29(8):1377-1388
The vascular endothelial growth factors VEGFA and VEGFC are crucial regulators of vascular development. They exert their effects by dimerization and activation of the cognate receptors VEGFR2 and VEGFR3. Here, we have used in situ proximity ligation to detect receptor complexes in intact endothelial cells. We show that both VEGFA and VEGFC potently induce formation of VEGFR2/‐3 heterodimers. Receptor heterodimers were found in both developing blood vessels and immature lymphatic structures in embryoid bodies. We present evidence that heterodimers frequently localize to tip cell filopodia. Interestingly, in the presence of VEGFC, heterodimers were enriched in the leading tip cells as compared with trailing stalk cells of growing sprouts. Neutralization of VEGFR3 to prevent heterodimer formation in response to VEGFA decreased the extent of angiogenic sprouting. We conclude that VEGFR2/‐3 heterodimers on angiogenic sprouts induced by VEGFA or VEGFC may serve to positively regulate angiogenic sprouting. 相似文献
186.
Background
Very often, encouraging or discouraging expressions are used in competitive contexts, such as sports practice, aiming at provoking an emotional reaction on the listener and, consequently, an effect on subsequent cognition and/or performance. However, the actual efficiency of these expressions has not been tested scientifically.Methodology/Principal Findings
To fill this gap, we studied the effects of encouraging, discouraging, and neutral expressions on event-related brain electrical activity during a visual selective attention task in which targets were determined by location, shape, and color. Although the expressions preceded the attentional task, both encouraging and discouraging messages elicited a similar long-lasting brain emotional response present during the visuospatial task. In addition, encouraging expressions were able to alter the customary working pattern of the visual attention system for shape selection in the attended location, increasing the P1 and the SP modulations while simultaneously fading away the SN.Conclusions/Significance
This was interpreted as an enhancement of the attentional processes for shape in the attended location after an encouraging expression. It can be stated, therefore, that encouraging expressions, as those used in sport practice, as well as in many other contexts and situations, do seem to be efficient in exerting emotional reactions and measurable effects on cognition. 相似文献187.
Laura A. Quimby Ayman S. Amer Sasha N. Zill 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2006,192(3):247-266
We studied the mechanisms underlying support of body load in posture and walking in serially homologous legs of cockroaches.
Activities of the trochanteral extensor muscle in the front or middle legs were recorded neurographically while animals were
videotaped. Body load was increased via magnets attached to the thorax and varied through a coil below the substrate. In posture,
tonic firing of the slow trochanteral extensor motoneuron (Ds) in each leg was strongly modulated by changing body load. Rapid
load increases produced decreases in body height and sharp increments in extensor firing. The peak of extensor activity more
closely approximated the maximum velocity of body displacement than the body position. In walking, extensor bursts in front
and middle legs were initiated during swing and continued into the stance phase. Moderate tonic increases in body load elicited
similar, specific, phase dependent changes in both legs: extensor firing was not altered in swing but was higher after foot
placement in stance. These motor adjustments to load are not anticipatory but apparently depend upon sensory feedback. These
data are consistent with previous findings in the hind legs and support the idea that body load is countered by common motor
mechanisms in serially homologous legs. 相似文献
188.
Anaya-Ramos Laura Díaz-Ruíz Araceli Ríos Camilo Mendez-Armenta Marisela Montes Sergio Aguirre-Vidal Yoshajandith García-Jiménez Sara Baron-Flores Veronica Monroy-Noyola Antonio 《Biometals》2021,34(6):1295-1311
BioMetals - Thallium (TI) is one of the most toxic heavy metals. Human exposure to Tl occurs through contaminated drinking water and from there to food, a threat to health. Recently, environmental... 相似文献
189.
During early pregnancy in the rat, focal adhesions disassemble in uterine luminal epithelial cells at the time of implantation
to facilitate their removal so that the implanting blastocyst can invade into the underlying endometrial decidual cells. This
study investigated the effect of ovarian hormones on the distribution and protein expression of two focal adhesion proteins,
talin and paxillin, in rat uterine luminal and glandular epithelial cells under various hormone regimes. Talin and paxillin
showed a major distributional change between different hormone regimes. Talin and paxillin were highly concentrated along
the basal cell surface of uterine luminal epithelial cells in response to oestrogen treatment. However, this prominent staining
of talin and paxillin was absent and also a corresponding reduction of paxillin expression was demonstrated in response to
progesterone alone or progesterone in combination with oestrogen, which is also observed at the time of implantation. In contrast,
the distribution of talin and paxillin in uterine glandular epithelial cells was localised on the basal cell surface and remained
unchanged in all hormone regimes. Thus, not all focal adhesions are hormonally dependent in the rat uterus; however, the dynamics
of focal adhesion in uterine luminal epithelial cells is tightly regulated by ovarian hormones. In particular, focal adhesion
disassembly in uterine luminal epithelial cells, a key component to establish successful implantation, is predominantly under
the influence of progesterone. 相似文献
190.
Laeyendecker O Church JD Oliver AE Mwatha A Owen SM Donnell D Brookmeyer R Musoke P Jackson JB Guay L Nakabiito C Quinn TC Eshleman SH 《PloS one》2010,5(10):e13259