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Correct Localization (correct + localization)

Distribution by Scientific Domains

Life Sciences	60%
Medical Sciences	40%

Selected Abstracts

Wingless can't fly so it hitches a ride with dynein

BIOESSAYS, Issue 10 2001
Steven H. Myster
Asymmetric RNA localization is required for many developmental processes in a wide range of organisms. For example, wingless and pair-rule transcripts are localized to the apical membrane of polarized cells. It has been unclear, however, if this localization is important for biological activity and, in addition, how the transcripts are transported. Two recent studies(1,2) have identified cis -elements and trans -acting factors that are required for the asymmetric localization of mRNAs. Correct localization is shown to be required for biological activity, and a mechanism of RNA transport involving the microtubule motor dynein has been revealed. BioEssays 23:869,872, 2001. © 2001 John Wiley & Sons, Inc. [source]

Development and selection of ,, T cells

IMMUNOLOGICAL REVIEWS, Issue 1 2007
Na Xiong
Summary:, Two main lineages of T cells develop in the thymus: those that express the ,, T-cell receptor (TCR) and those that express the ,, TCR. Whereas the development, selection, and peripheral localization of newly differentiated ,, T cells are understood in some detail, these processes are less well characterized in ,, T cells. This review describes research carried out in this laboratory and others, which addresses several key aspects of ,, T-cell development, including the decision of precursor cells to differentiate into the ,, versus ,, lineage, the ordered differentiation over the course of ontogeny of functional ,, T-cell subsets expressing distinct TCR structures, programming of ordered V, gene rearrangement in the thymus, including a molecular switch that ensures appropriate V, rearrangements at the appropriate stage of development, positive selection in the thymus of ,, T cells destined for the epidermis, and the acquisition by developing ,, T cells of cues that determine their correct localization in the periphery. This research suggests a coordination of molecularly programmed events and cellular selection, which enables specialization of the thymus for production of distinct T-cell subsets at different stages of development. [source]

Rga2 is a Rho2 GAP that regulates morphogenesis and cell integrity in S. pombe

MOLECULAR MICROBIOLOGY, Issue 4 2008
Ma Antonia Villar-Tajadura
Summary Schizosaccharomyces pombe Rho2 GTPase regulates ,-D-glucan synthesis and acts upstream of Pck2 to activate the MAP kinase pathway for cell integrity. However, little is known about its regulation. Here we describe Rga2 as a Rho2 GTPase-activating protein (GAP) that regulates cell morphology. rga2+ gene is not essential for growth but its deletion causes longer and thinner cells whereas rga2+ overexpression causes shorter and broader cells. rga2+ overexpression also causes abnormal accumulation of Calcofluor-stained material and cell lysis, suggesting that it also participates in cell wall integrity. Rga2 localizes to growth tips and septum region. The N-terminal region of the protein is required for its correct localization whereas the PH domain is necessary exclusively for Rga2 localization to the division area. Also, Rga2 localization depends on polarity markers and on actin polymerization. Rga2 interacts with Rho2 and possesses in vitro and in vivo GAP activity for this GTPase. Accordingly, rga2, cells contain more ,-D-glucan and therefore partially suppress the thermosensitivity of mok1,664 cells, which have a defective ,-D-glucan synthase. Additionally, genetic interactions and biochemical analysis suggest that Rga2 regulates Rho2,Pck2 interaction and might participate in the regulation of the MAPK cell integrity pathway. [source]

Cytoskeletal Changes in Oocytes and Early Embryos During in vitro Fertilization Process in Mice

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2010
E. Gumus
Summary The cytoskeleton plays crucial roles in the development and fertilization of germ cells and in the early embryo development. The growth, maturation and fertilization of oocytes require an active movement and a correct localization of cellular organelles. This is performed by the re-organization of microtubules and actin filaments. Therefore, the aim of the present study was to determine the changes in cytoskeleton during in vitro fertilization process using appropriate immunofluorescence techniques. While the chromatin content was found to be scattered throughout the nucleus during the oocyte maturation period, it was seen only around nucleolus following the completion of the maturation. Microtubules, during oocyte maturation, were regularly distributed throughout the ooplasm which was then localized in the subcortical region of oocytes. Similarly microfilaments were scattered throughout the ooplasm during the oocyte maturation period whereas they were seen in the subcortical region around the polar body and above the meiotic spindle throughout the late developmental stages. In conclusion, those changes occurred in microtubules and microfilaments might be closely related to the re-organization of the genetic material during the oocyte maturation and early embryo development. [source]

Development of a parathyroid database in Melbourne and review of the last 50 cases

ANZ JOURNAL OF SURGERY, Issue 9 2004
Meei J. Yeung
Background: Minimally invasive parathyroidectomy (MIP) is only possible if preoperative localization studies accurately identify the abnormal parathyroid tissue. The aim of the present paper was to evaluate the accuracy of these studies in our geographical region and the consequences on MIP. Methods: A Filemaker Pro database was designed and a retrospective analysis was carried out on the last 50 parathyroidectomies. Results: There were a total of 49 patients who underwent parathyroidectomy; with one patient having two operations. Forty-nine preoperative ultrasound localization studies were performed. Ultrasound sensitivity of correct localization of abnormal parathyroids was 41% with a false positive rate of 25%. Twenty-two sestamibi scans identified 14 abnormal parathyroids. Sestamibi scanning had a sensitivity of 32% for correct localization and a false positive rate of 32%. There were 16 different radiologists or nuclear medicine physicians involved with the nuclear medicine scans, and 22 different radiologists involved in the preoperative ultrasound scans. Forty-seven patients were cured of hyperparathyroidism after a primary operation, with a total of 48 patients in all being cured following re-exploration. One patient was lost to follow up. The success of primary exploration was therefore 96% and following re-exploration this increased to 98%. Conclusion: We found preoperative localization studies to have low sensitivities and high false positive rates. To move successfully towards MIP, we need to identify a radiologist with a special interest in localization studies to achieve greater accuracy. [source]