Transmembrane segments of nascent polytopic membrane proteins control cytosol/ER targeting during membrane integration

Vastly different folded transmembrane segments of nascent multispanning membrane proteins each induce structural changes in the ribosome tunnel and translocon that target the loops of the growing polypeptide alternately into the cytosol or ER lumen

SB04-22/23: Resolution Authorizing Approval of Staff Senate Signature of Bear Necessities Statement to University Administration

Passed during May 10, 2023 Staff Senate meeting. Documents from the May 10, 2023 meeting of the University of Montana S by University of Montana--Missoula. Staff Senate (umt.edu) Resolution authorizing approval of Staff Senate to sign support to the ASUM Bear Necessities statement to the University of Montana Administration. Resolution Authored by Kat Cowley. Additional Authors, including Cowley, listed for letter. Letter discusses concerns regarding the status of marginalized and vulnerable student populations and offers suggestions on some ways the University of Montana can support students at a basic human level. These include continued advocacy for increase support from the State of Montana, increased housing availability, meal plan affordability, open education resources, campus accessibility, and addressing staffing issues

Polytopic membrane protein folding at L17 in the ribosome tunnel initiates cyclical changes at the translocon

Interaction between L17 in the ribosome tunnel and folded nascent chain transmembrane segments during multi-spanning membrane protein synthesis triggers structural rearrangements in the ribosome that cause switching between cytosolic and ER lumenal targeting of the growing polypeptide

A diachronic study of the Mediterranean coastline: A geometric approach

Coastal areas represent one of the country's most important environmental and economic resources. They are naturally dynamic, with changes that can occur on a human time scale and that need to be quantified for the proper management of shorelines and, in particular, the beaches on which the local economy is largely based. This work focuses on the diachronic study of the coastline of the Mediterranean coast, particularly the coastal fringe at the mouth of the Wadi Aliane. In order to assess and remedy the risks of erosion and accretion of the coastline, the methodology followed consists of the application of automatic analytical techniques using multi-temporal photo-interpretation, a Geographic Information System (GIS) and a Digital Shoreline Analysis System (DSAS). The rate of change will be calculated from the multi-date maps, (1981- 1997 and 2016) using the End Point Rate (EPR) index. Comparison of the results of the interpretation of aerial photos and satellite images of the Oued Aliane coastline used (1981, 1997, and 2016) provided information that allowed us to understand the evolutionary behaviour of the wet sand/dry sand line over 36 years. This numerical analysis of the 1981 -1997 and 2016 coastlines in the coastal sector of Oued Aliane, shows us that zones A, C and D are mainly affected by erosion, while the mouth part is affected by accretion because it is considered a delta and therefore a sedimentation area

Inhibition of human glutathione S-transferase P1-1 by the flavonoid quercetin

In the present study, the inhibition of human glutathione S-transferase P1-1 (GSTP1-1) by the flavonoid quercetin has been investigated. The results show a time- and concentration-dependent inhibition of GSTP1-1 by quercetin. GSTP1-1 activity is completely inhibited upon I h incubation with 100 muM quercetin or 2 h incubation with 25 muM quercetin, whereas 1 and 10 muM quercetin inhibit GSTP1-1 activity to a significant extent reaching a maximum of 25 and 42% inhibition respectively after 2 h. Co-incubation with tyrosinase greatly enhances the rate of inactivation, whereas co-incubation with ascorbic acid or glutathione prevents this inhibition. Addition of glutathione upon complete inactivation of GSTP1-1 partially restores the activity. Inhibition studies with the GSTP1-1 mutants C47S, C101S and the double mutant C47S/C101S showed that cysteine 47 is the key residue in the interaction between quercetin and GSTP1-1. HPLC and LGMS analysis of trypsin digested GSTP1-1 inhibited by quercetin did not show formation of a covalent bond between Cys 47 residue of the peptide fragment 45-54 and quercetin. It was demonstrated that the inability to detect the covalent quercetin-peptide adduct using LGMS is due to the reversible nature of the adduct-formation in combination with rapid and preferential dimerization of the peptide fragment once liberated from the protein. Nevertheless, the results of the present study indicate that quinone-type oxidation products of quercetin likely act as specific active site inhibitors of GSTP1-1 by binding to cysteine 47. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved