We have discovered a novel cortical patch structure in Saccharomyces cerevisiae defined by a family of integral plasma membrane proteins, including Sur7p, Ynl194p, and Ydl222p. Sur7p-family patches localized as cortical patches that were immobile and stable. These patches were polarized to regions of the cell with a mature cell wall; they were absent from small buds and the tips of many medium-sized buds. These patches were distinct from other known cortical structures. Digestion of the cell wall caused Sur7p patches to disassemble, indicating that Sur7p requires cell wall-dependent extracellular interactions for its localization as patches. sur7⌬, ydl222⌬, and ynl194⌬ mutants had reduced sporulation efficiencies. SUR7 was originally described as a multicopy suppressor of rvs167, whose product is an actin patch component. This suppression is probably mediated by sphingolipids, since deletion of SUR7, YDL222, and YNL194 altered the sphingolipid content of the yeast plasma membrane, and other SUR genes suppress rvs167 via effects on sphingolipid synthesis. In particular, the sphingoid base length and number of hydroxyl groups in inositolphosphorylceramides were altered in sur7⌬, ydl222⌬, and yne194⌬ strains.The importance of membrane domains and local differences in membrane composition and structure has been described for several processes, including endocytosis, signaling through caveoli, and protein trafficking (17,32,34). For the yeast Saccharomyces cerevisiae, two reports have presented evidence for detergent-insoluble plasma membrane lipid rafts, which are important for protein sorting through the endoplasmic reticulum and Golgi (2, 30). Also, septins maintain the daughter cell plasma membrane as a domain with distinct markers from the mother's plasma membrane (4, 49). However, most yeast plasma membrane proteins, whether integral, peripheral, or glycosylphosphatidylinositol anchored, are dispersed evenly throughout the plasma membrane. With the notable exception of actin patch components, relatively few proteins are known to localize as patches or domains associated with the plasma membrane.SUR7 was originally identified as a multicopy suppressor of mutations in rvs161 and/or rvs167 (45). rvs161 and rvs167 mutants have reduced viability upon starvation (6, 13) and are also defective in actin polarization, bipolar bud site selection (6, 19, 44), endocytosis (35), and sporulation (12, 15). Overexpression of SUR7 suppressed rvs161 and rvs167 defects in actin polarization, bud site selection, and growth (45). rvs161 and rvs167 are also suppressed by loss-of-function mutations in the nonessential genes sur1, sur2, and sur4 (15). Sur1p, Sur2p, and Sur4p are a mannosyl-transferase, a hydroxylase, and an acyl chain elongation protein, respectively, all involved in sphingolipid biosynthesis (see references 16 and 42).The Sur7p family includes three members in S. cerevisiae: Sur7p, Ynl194p, and Ydl222p. They are predicted to be integral membrane proteins; each has a signal sequence and three transmembrane helices (45...

A major feature of epithelial cell polarity is regulated positioning of the mitotic spindle within the cell. Spindles in cells of symmetrically expanding tissues are predicted to align parallel to the tissue plane. Direct measurement of this alignment has been difficult in mammalian tissues. Here, we analyzed the position of spindles in intact mouse intestinal epithelium using microtubule immunofluorescence and three-dimensional confocal imaging. Mitotic cells were identified in the proliferative zone of intestinal crypts. Spindle angle relative to the apical cell surface was determined either by direct measurement from confocal images or with a computational algorithm. Angles averaged within 10 degrees of parallel to the apical surface in metaphase and anaphase cells, consistent with robust planar spindle positioning, whereas spindles in prometaphase cells showed much greater angle variability. Interestingly, cytokinetic furrows appeared to extend from the basal cell surface toward the apical surface. This type of image analysis may be useful for studying the regulation of spindle position during tissue remodeling and tumor formation.

Background/Aims-Hepatitis C virus (HCV) infection is a global medical problem. The current standard treatment of chronic hepatitis C (CHC), pegylated interferon plus ribavirin, is prolonged, expensive, has serious side effects and, at best, is only 50% effective. Silymarin is a natural antioxidant often used by patients with CHC, although its efficacy for decreasing HCV levels or ameliorating CHC remains uncertain. HCV infection is associated with increased hepatic oxidative stress, and one of the antioxidant enzymes which protect cells against this stress is heme oxygenase-1 (HO-1).

Purpose of the review Psychiatrists and other mental health professionals typically assist with evaluating and treating psychiatric and behavioral issues in transplant candidates, recipients and living organ donors. In this review recent findings on specific psychiatric issues in adult solid organ transplant candidates and recipients, as well as living donors are discussed as well as their relevance to clinical practice. Recent findings Patients with complex mental health and addiction histories can have outcomes similar to patients without these disorders but may require specialized pre-transplant preparation or post-transplant interventions to optimize their outcomes. Specific attention to the preparation and wellbeing of living donors is needed. Summary As transplant programs increasingly consider patients with complex mental health histories, psychiatrists and mental health professionals evaluating and treating these patients need to consider plans for early identification and treatment. Psychiatric care provided across the pre- to post-operative periods will best address the longitudinal care needs of patients with mental health disorders. Abstinence from substances and complete adherence to medical directives provides the best chance for optimal outcomes. Treatment of depression may improve transplant outcomes. Research is needed to identify effective interventions and the best strategies to engage patients to improve adherence.

No abstract