Browsing by Subject "Intracellular localization"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Publication
    Open Access
    Fhit protein is preferentially expressed in the nucleus of monocyte-derived cells and its possible biological significance
    (Murcia : F. Hernández, 2006) Zhao, P.; Hou, N.; Lu, Y.
    The FHIT gene encompassing the most active common human fragile region, FRA3B, has been proposed as a tumour suppressor gene for important common human carcinomas. The mechanism in which Fhit protein exerts its tumour suppressor activity is still obscure. To further understand the Fhit function associated with its intracellular localization we have investigated its cellular localization and distribution in human normal and cancerous tissues. Data of 1500 samples from immunohistochemistry showed that Fhit protein was preferentially and stably expressed in the nucleus of monocyte-derived or histiocytic lineage cells including monocytes of the circulating blood cells, macrophages of the connective tissue, Kupffer cells of the liver, alveolar macrophages or dust cells of the lung, osteoclasts of bone, microglia of the brain, epithelioid cells under chronic inflammatory conditions, foreignbody giant cells, Langerhans cells of the epidermis and dendritic cells of various kinds of human tissue, although the protein could also be infrequently observed in the nucleus of some quiescent epithelial cells. In active cells other than histiocytes, Fhit protein was detected either in cytoplasm or was negative. Neurons expressed Fhit strongly and neuroglial cells did so moderately but only in the cytoplasm. There was no Fhit protein detected in the neutrophils, lymphocytes, plasma cells and lipocytes. The present data showes that the stable nuclear localization of Fhit is not only a special marker for histiocytes with various morphologies but also may suggest the other function concerning Fhit as a signaling molecule related to anti-proliferation function. The detailed biological function related to nuclear localization of Fhit protein in the histiocytes remains to be further studied.
  • Thumbnail Image
    Publication
    Open Access
    To NO or not to NO, where, is the question
    (Murcia : F. Hernández, 2004) Govers, R.; Oess, S.
    Nitric oxide (NO) is a gaseous radical with unique biological functions essential for the cardiovascular system, host defense and neurotransmission. For two decades it was thought that NO was able to diffuse freely across relatively long distances and to traverse major parts of the cell, if not multiple cell layers. However, NO has been proven to be extremely reactive: it reacts with other reactive oxygen species, heavy metals, as well as with cysteine and tyrosine residues in proteins. In accordance, it is now widely accepted that once NO is generated, it is very short-lived and diffuses only over a short distance. This urges for the local production of NO and the localization of NO synthases in the proximity of their downstream targets. This review discusses the highly organized localization of NO synthases, with the endothelial isoform (eNOS) as its main focus, since from this synthase most is known about its subcellular localization and regulation.