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51.

Background

A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.

Methods

FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.

Results

LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.

Conclusion

Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.
  相似文献   
52.

Introduction  

The aim of this study was to investigate whether serum biomarker levels of C2C, C1,2C, CS846, and CPII can predict the long-term course of disease activity and radiographic progression early in the disease course of rheumatoid arthritis (RA).  相似文献   
53.
54.
Zusammenfassung Die Zellwand verschiedener Hefen konnte durch Behandlung mit Schneckenenzym verdaut werden. Bei Einhalten bestimmter Bedingungen war damit stets ein Freiwerden von intakten Protoplasten verbunden. Die Lyse der Zellwand wurde von verschiedenen Faktoren, so z.B. dem Alter der Kultur und der Zusammensetzung des Nährmediums beeinflußt. Aus folgenden Hefen konnten durch Einwirkung von Schnekkenenzym Protoplasten gewonnen werden: Saccharomyces fragilis, Saccharomyces cerevisiae var. ellipsoideus, Saccharomyces willianus, Schizosaccharomyces pombe, Saccharomycodes ludwigii und Sporobolomyces. Die Protoplasten existierten nur, wenn sie durch bestimmte hypertonische Medien stabilisiert wurden. Ammonsulfat war als Stabilisator am besten geeignet. Suspendieren in Aqua dest. oder Zugabe von oberflächenaktiven Substanzen, z.B. Natriumdodecylsulfat, führte sofort zur Lyse.  相似文献   
55.

Background  

Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD.  相似文献   
56.
Liu J  Hegyi H  Acton TB  Montelione GT  Rost B 《Proteins》2004,56(2):188-200
A central goal of structural genomics is to experimentally determine representative structures for all protein families. At least 14 structural genomics pilot projects are currently investigating the feasibility of high-throughput structure determination; the National Institutes of Health funded nine of these in the United States. Initiatives differ in the particular subset of "all families" on which they focus. At the NorthEast Structural Genomics consortium (NESG), we target eukaryotic protein domain families. The automatic target selection procedure has three aims: 1) identify all protein domain families from currently five entirely sequenced eukaryotic target organisms based on their sequence homology, 2) discard those families that can be modeled on the basis of structural information already present in the PDB, and 3) target representatives of the remaining families for structure determination. To guarantee that all members of one family share a common foldlike region, we had to begin by dissecting proteins into structural domain-like regions before clustering. Our hierarchical approach, CHOP, utilizing homology to PrISM, Pfam-A, and SWISS-PROT chopped the 103,796 eukaryotic proteins/ORFs into 247,222 fragments. Of these fragments, 122,999 appeared suitable targets that were grouped into >27,000 singletons and >18,000 multifragment clusters. Thus, our results suggested that it might be necessary to determine >40,000 structures to minimally cover the subset of five eukaryotic proteomes.  相似文献   
57.
The origin of midgut epithelium may begin either from yolk cells (energids), tips of stomo- and proctodaeum (ectoderm), inner layer (endoderm) or from both kinds of the above mentioned cells. The origin of the midgut epithelium in wingless insects (Apterygota) has still not been determined. In Thermobia domestica the formation of midgut is much delayed, and it completes in the post-embryonic stage, while the stomo- and the proctodaeum are well-developed in the embryonic period. The energids, which remain inside the yolk, start to migrate to its periphery, where they arrange singly close to cell membrane. The yolk mass with the energids at the 14th day of embryogenesis are referred to as the primary midgut. During the first instar larval stage more and more energids migrate to the yolk periphery and the cell membrane starts to form numerous foldings surrounding the groups of energids, which in turn lead to formation of isolated regenerative cell groups. Eventually the cell membrane invaginations reach the center of the yolk mass. Large cells of the primary epithelium, surrounding the newly formed midgut lumen are formed. The cells of the primary epithelium are filled with yolk and are equipped with microvilli pointing to the midgut lumen. As the yolk is being digested, the process of the primary epithelium cells degeneration begins. The cells are getting shorter and start to degenerate. The definitive midgut epithelium is formed from proliferating regenerative cells. It consists of regularly spaced regenerative cell groups as well as the epithelial cells. The ultrastructure of both these cell groups has been described.  相似文献   
58.
During caryopsis development the layers of the pericarp, integuments, and nucellus all contribute to the formation of the caryopsis coat. The coat consists of a layer of outer pericarp epidermal transfer cells, a collapsed and senescent layer of middle pericarp cells, and a discontinuous layer of inner pericarp epidermal transfer cells. The latter is not present across the placental pad. The integuments are present as a collapsed dense layer, the nucellus is discontinuous and cellular. The placental pad occurs at the ventral surface of the caryopsis, opposite the scutellum and coleorhiza. It consists of 15–20 collapsed cell layers, including the pigment strand and placental vascular bundle. From the inside several partially collapsed cell layers of the nucellar projection occur which contain transfer-cell walls. The middle dense layers, the pigment strand, consist of the middle pericarp remnant, plus the remains of the placental vascular bundle. The pericarp inner epidermis does not extend across the pad. The aleurone layer is a continuous uniseriate layer around the entire caryopsis except at the placental pad; here it is crushed and contains the remnant of a transfer-cell wall. The outer pericarp epidermis is a continuous layer of transfer cells across the pad. These cells contain membranous inclusions suggesting that they may be functional during germination.  相似文献   
59.
MOTIVATION: The study of biological systems, pathways and processes relies increasingly on analyses of networks. Most often, such analyses focus on network topology, thereby treating all proteins or genes as identical, featureless nodes. Integrating molecular data and insights about the qualities of individual proteins into the analysis may enhance our ability to decipher biological pathways and processes. RESULTS: Here, we introduce a novel platform for data integration that generates networks on the macro system-level, analyzes the molecular characteristics of each protein on the micro level, and then combines the two levels by using the molecular characteristics to assess networks. It also annotates the function and subcellular localization of each protein and displays the process on an image of a cell, rendering each protein in its respective cellular compartment. By thus visualizing the network in a cellular context we are able to analyze pathways and processes in a novel way. As an example, we use the system to analyze proteins implicated with Alzheimers disease and show how the integrated view corroborates previous observations and how it helps in the formulation of new hypotheses regarding the molecular underpinnings of the disease. AVAILABILITY: http://www.rostlab.org/services/pinat.  相似文献   
60.
Data considering the degeneration and regeneration of the midgut epithelium in the primitive wingless insects, such as Collembola, are rather poor. Also information, which treats the regenerative cells as the primordial cells, is poorly known. The midgut epithelium of Podura aquatica L. (Insecta, Collembola, Arthropleona) is formed by the epithelial and regenerative cells. The epithelial cells show distinct regionalisation in the organelles distribution. The ultrastructure of the basal, perinuclear and apical regions of the epithelial cells is described. As in insects without Malpighian tubules, structures which resemble urospherites occur in the cytoplasm of the epithelial cells. After degeneration of the entire midgut epithelium, a new epithelium is formed from regenerative cells. During the process of regeneration, the degenerated epithelium gradually is separated from the basal lamina by the newly formed one. Finally, the detached epithelium is moved into the midgut lumen. Regenerative cells play a role of primordial cells during epithelial regeneration.  相似文献   
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