163 research outputs found
Is Dower Abolished?
Otofaji (kendini yeme) hasarlı hücresel proteinleri ve organelleri ortadan kaldıran evrimsel bir süreçtir. Otofaji uyarılınca bozunuma uğrayan sitoplazma ve organeller veziküller içine alınır. Şekillenen veziküller mayalarda vakuole, memeli hücrelerinde lizozoma gön-derilir. Açlık veya oksidatif stres gibi durumlarda ya da normal koşullar altında makromoleküllerin bozunumu ve besin dengesinin sağlanması otofaji aracılığıyla dü-zenlenir. Ökaryotik hücrelerde otofaji, oluşma şekline göre makro-otofaji, mikro-otofaji ve şaperon aracılı otofaji olarak sınıflandırılır. Bunların hepsi lizozomda sitosolik bileşenlerin proteolitik bozunmasını teşvik eder ve otofajiye bağlı genler ve bunlarla ilişkili enzim-ler aracılığıyla düzenlenirler. Makro-otofaji ve mikro-otofaji bağımlı lizozomal/vakuoler yıkım süreci ya seçi-ci olmaz (non-selektif) ya da seçicidir (selektif). Şaperon aracılı otofaji yanlış katlanmış veya yanlışlıkla oluşturulmuş sitosolik proteinleri indirgemek için kulla-nılan bir seçici otofajidir. Seçici olmayan makro-otofajide sitoplazma otofagozom oluşumuyla, mikro-otofajide ise çözünebilir intrasellüler substratlar boru biçimindeki invaginasyonlarla lizozom/vakuol içine alınır. Seçici makro- ya da mikro-otofaji sayısı artan ya da hasar görmüş olan çeşitli organeller ile invaziv mik-ropları hedef alır. Bu durumda otofaji kargo içeriğine göre retikulofaji veya ERfaji, pekzofaji, mitofaji, lipofaji, zimofaji, nükleofaji, ribofaji, agrefaji ve ksenofaji gibi özel isimlerle tanımlanır. Bu derlemede doğru hücresel fonksiyonları korumak için hasarlı organelleri, protein yığınlarını ve hücre içi patojenleri yok eden bir sitoprotektif program olarak işlev gören otofaji ele alınmıştır.Autophagy (self-eating) is an evolutionary process that removes damaged cellular proteins and organelles. When autophagy is induced, degrading cytoplasm and organelles are taken up into vesicles. . These vesicles are sent to the vacuolated or lysosomes in the yeast and mammalian cells, respectively. Provision of degradation of macromolecules and nutrient balance under stress conditions, such as starvation or oxidative stress or under normal conditions, is regulated by autophagy. In eukaryotic cells, autophagy is classified as macro-autophagy, micro-autophagy and chaperone-mediated autophagy according to the formation pattern. All of these promote the proteolytic degradation of cytosolic components in the lysosome and are regulated by autophage-linked genes and their associated enzymes. Macro-autophagy and micro-autophagy dependent lysosomal/vacuolar degradation processes are either non-selective or selective (selective). Chaperone-mediated autophagy is a selective autophagy used to reduce unfolded or misfolded cytosolic proteins. In the non-selective macro-autophagy, the cytoplasm is incorporated into the lysosome/vacuole by autophagosome, while in the micro-autophagy the soluble intracellular substrates are introduced into the lysosome/vacuole via tubular invaginations. The selective macro- or micro-autophagy target invasive microorganisms with various organelles that are either increased in number or damaged. In this case, autophagy is defined by special names such as reticulophagy or ERphagy, pexophagy, mitophagy, lipophagy, zimophagy, nucleophagy, ribophagy, aggrephagy and ksenophagy, according to the contents of the cargo. This review focuses on autophagy that functions as a cytoprotective program that destroys damaged organelles, protein deposits and intracellular pathogens in order to preserve the correct cellular functions.</p
Heat shock proteins (HSP)-60,-70,-90, and 105 display variable spatial and temporal immunolocalization patterns in the involuting rat uterus
Uterine involution involves substantial tissue destruction and subsequent repair and remodelling, with similarities to the microenvironments present during wound healing. Although involution is a physiologically normal process, it may generate a stressful microenvironment for the uterine cells, and thus it can induce the expression of heat shock proteins (HSPs), which were originally identified as stress-responsive proteins. The aim of this study was to determine the spatial and temporal expression and localization of four heat shock proteins (HSPD1/HSP60, HSPA/HSP70, HSPC/HSP90 and HSPH1/HSP105/110) in the involuting rat uterus using immunohistochemistry. The HSPs were expressed in the luminal (LE) and glandular epithelium (GE), fibroblasts, mast cells, myometrial myocytes, perimetrial mesothelium and blood vessels, and each of the uterine tissues had distinctive patterns of HSP immunostaining. HSPD1/HSP60 was located in the cytoplasm, often with the granular appearance that is typical of organellar localization, whereas HSPA/HSP70, HSPC/HSP90 and HSPH1/HSP105 were located in the nucleus and cytoplasm. The immunolocalization patterns of all HSPs in the LE showed alterations that accompanied involution, but no difference was observed in the other uterine cells. HSPs were localized in the apical and basal cytoplasm of the LE on postpartum days 1, 5 and 10, but only in the apical cytoplasm on day 3. Furthermore, on day 3, HSPA/HSP70, HSPC/HSP90 and HSPH1/HSP105 immunostaining in the crypts and GE were stronger than those in the LE, whereas on day 10, the nuclear HSP90 immunoreaction was stronger in the LE than in the GE. These observations suggest that HSPs may be involved in many physiological processes, such as cell cycle control, cell proliferation, regulation of cell death and survival, and differentiation during the involution process.Uterine involution involves substantial tissue destruction and subsequent repair and remodelling, with similarities to the microenvironments present during wound healing. Although involution is a physiologically normal process, it may generate a stressful microenvironment for the uterine cells, and thus it can induce the expression of heat shock proteins (HSPs), which were originally identified as stress-responsive proteins. The aim of this study was to determine the spatial and temporal expression and localization of four heat shock proteins (HSPD1/HSP60, HSPA/HSP70, HSPC/HSP90 and HSPH1/HSP105/110) in the involuting rat uterus using immunohistochemistry. The HSPs were expressed in the luminal (LE) and glandular epithelium (GE), fibroblasts, mast cells, myometrial myocytes, perimetrial mesothelium and blood vessels, and each of the uterine tissues had distinctive patterns of HSP immunostaining. HSPD1/HSP60 was located in the cytoplasm, often with the granular appearance that is typical of organellar localization, whereas HSPA/HSP70, HSPC/HSP90 and HSPH1/HSP105 were located in the nucleus and cytoplasm. The immunolocalization patterns of all HSPs in the LE showed alterations that accompanied involution, but no difference was observed in the other uterine cells. HSPs were localized in the apical and basal cytoplasm of the LE on postpartum days 1, 5 and 10, but only in the apical cytoplasm on day 3. Furthermore, on day 3, HSPA/HSP70, HSPC/HSP90 and HSPH1/HSP105 immunostaining in the crypts and GE were stronger than those in the LE, whereas on day 10, the nuclear HSP90 immunoreaction was stronger in the LE than in the GE. These observations suggest that HSPs may be involved in many physiological processes, such as cell cycle control, cell proliferation, regulation of cell death and survival, and differentiation during the involution process.</p
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