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81.
82.
Rorgamma (Rorc) is a common integration site in type B leukemogenic virus-induced T-cell lymphomas
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The retrovirus type B leukemogenic virus (TBLV) causes T-cell lymphomas in mice. We have identified the Rorgamma locus as an integration site in 19% of TBLV-induced tumors. Overexpression of one or more Rorgamma isoforms in >77% of the tumors tested may complement apoptotic effects of c-myc overexpression. 相似文献
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Ernesto Maldonado Fabiola Hernandez Carlos Lozano Marta E. Castro Rosa E. Navarro 《Pigment cell & melanoma research》2006,19(4):315-326
Hypopigmentation is a characteristic of several diseases associated with vesicle traffic defects, like the Hermansky–Pudlak, Chediak–Higashi, and Griscelli syndromes. Hypopigmentation is also a characteristic of the zebrafish mutant vps18hi2499A, which is affected in the gene vps18, a component of the homotypic fusion and protein sorting complex that is involved in tethering during vesicular traffic. Vps18, as part of this complex, participates in the formation of early endosomes, late endosomes, and lysosomes. Here, we show that Vps18 is also involved in the formation of melanosomes. In the zebrafish mutant vps18hi2499A the retroviral insertion located at exon 4 of vps18, leads to the formation of two abnormal splicing variants lacking the coding sequence for the clathrin repeat and the RING finger conserved domains. A deficiency of Vps18 in zebrafish larvae results in hepatomegaly and skin hypopigmentation. We also observed a drastic reduction in the number of melanosomes in the eye's retinal pigmented epithelium along with the accumulation of immature melanosomes. A significant reduction in the vps18hi2499A larvae visual system capacity was found using the optokinetic response assay. We propose that the insertional mutant vps18hi2499A can be used as a model for studying hypopigmentation diseases in which vesicle traffic problems exist. 相似文献
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Morales-Bozo I Rojas G Ortega-Pinto A Espinoza I Soto L Plaza A Lozano C Urzúa B 《Gerodontology》2012,29(2):e1103-e1112
doi: 10.1111/j.1741‐2358.2012.00626.x Evaluation of the efficacy of two mouthrinses formulated for the relief of xerostomia of diverse origin in adult subjects Objective: To evaluate the efficacy of two new mouthrinses in the reduction of xerostomía‐associated symptomatology. Background: Xerostomia is a common chronic health condition that affects a great number of adults and significantly deteriorates quality of life, such that treatment is necessary. Materials and methods: Sixty‐seven adult subjects of both sexes presenting xerostomia of diverse origin were selected. Mouthrinses were tested using a double‐blind, randomized, cross‐over clinical trial with an intervining wash out period. Results: The 100% of subjects presented sensation of dry mouth, and 86% stated sensation of thick saliva. Burning tongue sensation, need to drink liquids to swallow and the sensation of swallowing difficulty were recorded in more than 50% of the patients. The most frequent pathologies in the sample were depression, arthritis, and arterial hypertension. Results of the clinical tests showed that mouthrinse 1 relieves sensation of dry mouth, need to drink liquids, and swallowing difficulty. In contrast, mouthrinse 2 relieves only latter two symptoms. Both rinses were more effective in relieving xerostomía‐associated symptomatology in patients taking 3 or more medicines simultaneously. Conclusion: Both mouthrinses were effective in relieving various xerostomia symptoms, could be distributed at a low cost, thereby improving the quality of life of population affected. 相似文献
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Mouse mammary tumor virus (MMTV) encodes a Rev-like protein, Rem, which is involved in the nuclear export and expression of viral RNA. Previous data have shown that all Rev-like functions are localized to the 98-amino-acid signal peptide (SP) at the N terminus of MMTV Rem or envelope proteins. MMTV-SP uses endoplasmic reticulum-associated degradation (ERAD) for protein trafficking. Rem cleavage by signal peptidase in the ER is necessary for MMTV-SP function in a reporter assay, but many requirements for trafficking are not known. To allow detection and localization of both MMTV-SP and the C-terminal cleavage product, we prepared plasmids expressing green fluorescent protein (GFP) tags. N-terminal Rem tagging led to protein accumulation relative to untagged Rem and allowed signal peptidase cleavage but reduced its specific activity. C-terminal tagging also led to Rem accumulation yet dramatically reduced cleavage, GFP fluorescence, and activity relative to N-terminally tagged Rem (GFPRem). Substitutions of an invariant leucine at position 71 between the known RNA-binding and nuclear export sequences interfered with GFPRem accumulation and activity but not cleavage. Similarly, deletion of 100 or 150 C-terminal amino acids from GFPRem dramatically reduced both Rem and MMTV-SP levels and function. Removal of the entire C terminus (203 amino acids) restored both protein levels and activity of MMTV-SP. Only C-terminal GFP tagging, and not other modifications, appeared to trap Rem in the ER membrane. Thus, Rem conformation in both the ER lumen and cytoplasm determines cleavage, retrotranslocation, and MMTV-SP function. These mutants further characterize intermediates in Rem trafficking and have implications for all proteins affected by ERAD. 相似文献
88.
Portal-Núñez S Lozano D de la Fuente M Esbrit P 《Revista espa?ola de geriatría y gerontología》2012,47(3):125-131
Deterioration of organ and systems function are the principal signs of aging. Aging is also believed to be a major factor in the loss of bone mass and quality, which in turn leads to an increase in the risk of fractures. Several factors seem to contribute to this scenario, with metabolic changes related to aging in the bone tissue itself being among them. Most of the current knowledge on the mechanisms associated with osteopenia/osteoporosis during aging has been generated from research in animal models (mainly rats and mice) and cell cultures derived from subjects of different ages. In this work, we have reviewed and summarised these studies, which have begun to establish the physiological and molecular basis of the bone alterations related to aging. 相似文献
89.
Dicer-2 is a ribonuclease involved in the insect RNAi pathway. On attempting to knockdown Dicer-2 expression in the insect Blattella germanica by RNAi, we found that treatment with Dicer-2 dsRNA upregulated the targeted mRNA. This unexpected result was also observed after treating with a nucleopolyhedrovirus dsRNA. Experiments with this alien dsRNA showed an all-or-none response with a threshold for inducing Dicer-2 upregulation between 0.4 and 0.04 μg in terms of dsRNA concentration and between 50 and 20 bp in terms of dsRNA length. The response seems specific of dsRNA given that equivalent experiments carried out with dsDNA did not affect Dicer-2 expression. In insects, Dicer-2 is postulated to be a sensor of viral infections and a key antiviral defense element. The upregulation of Dicer-2 expression after dsRNA administration fits well with this sensor role, and the occurrence of this mechanism in B. germanica, a phylogenetically basal insect, suggests that sensing alien RNAs might be an ancestral function of Dicer-2 proteins. 相似文献
90.
A Ramírez-Bautista BP Stephenson A Lozano H Uribe-Rodríguez A Leyte Manrique 《Ecology and evolution》2012,2(8):1903-1913
The spiny lizard Sceloporus grammicus (Squamata: Phrynosomatidae) is a small reptile from central México and the southern United States, occurring in a wide geographic area characterized by extensive variation in topographic and climatic regimes. Genetic variation among lineages from central México is substantial, though the extent to which this variation corresponds with life-history traits remains obscure. To address part of this puzzle, we studied a population of S. grammicus from Tepeapulco, Hidalgo, México. Male-biased sexual dimorphism was extensive in this population; males were larger than females overall, and expressed proportionately larger heads and longer limbs. Minimum size at sexual maturity was similar in the sexes (males: 43 mm; females: 42 mm). In contrast to other populations from the Central Plateau, reproductive activity of males and females was synchronous. Testicular recrudescence of adult males was initiated in October-November, and maximum testis size maintained from December to July. Female reproductive activity showed no clear seasonal pattern: females had vitellogenic follicles from October to July, and pregnant females were found throughout the year. Female body size was not related to litter size. Neither male nor female gonadal mass was correlated with any abiotic environmental variable examined. Differences in reproductive characteristics among populations of S. grammicus might be indicative of plasticity in response to local environmental conditions, local adaptation, or complex gene × environment interactions. We consider these results in the context of previously studied populations of S. grammicus from the Central Plateau and elsewhere, and propose directions for future research. 相似文献