Hrk1 Plays Both Hog1-Dependent and -Independent Roles in Controlling Stress Response and Antifungal Drug Resistance in Cryptococcus neoformans

The HOG (High Osmolarity Glycerol response) pathway plays a central role in controlling stress response, ergosterol biosynthesis, virulence factor production, and differentiation of Cryptococcus neoformans, which causes fatal fungal meningoencephalitis. Recent transcriptome analysis of the HOG pathway discovered a Hog1-regulated gene (CNAG_00130.2), encoding a putative protein kinase orthologous to Rck1/2 in Saccharomyces cerevisiae and Srk1 in Schizosaccharomyces pombe. Its function is not known in C. neoformans. The present study functionally characterized the role of Hrk1 in C. neoformans. Northern blot analysis confirmed that HRK1 expression depends on the Hog1 MAPK. Similar to the hog1Δ mutant, the hrk1Δ mutant exhibited almost complete resistance to fludioxonil, which triggers glycerol biosynthesis via the HOG pathway. Supporting this, the hrk1Δ mutant showed reduced intracellular glycerol accumulation and swollen cell morphology in response to fludioxonil, further suggesting that Hrk1 works downstream of the HOG pathway. However, Hrk1 also appeared to have Hog1-independent functions. Mutation of HRK1 not only further increased osmosensitivity of the hog1Δ mutant, but also suppressed increased azole-resistance of the hog1Δ mutant in an Erg11-independent manner. Furthermore, unlike the hog1Δ mutant, Hrk1 was not involved in capsule biosynthesis. Hrk1 was slightly involved in melanin production but dispensable for virulence of C. neoformans. These findings suggest that Hrk1 plays both Hog1-dependent and –independent roles in stress and antifungal drug susceptibility and virulence factor production in C. neoformans. Particularly, the finding that inhibition of Hrk1 substantially increases azole drug susceptibility provides a novel strategy for combination antifungal therapy

Electrically Guiding Migration of Human Induced Pluripotent Stem Cells

A major road-block in stem cell therapy is the poor homing and integration of transplanted stem cells with the targeted host tissue. Human induced pluripotent stem (hiPS) cells are considered an excellent alternative to embryonic stem (ES) cells and we tested the feasibility of using small, physiological electric fields (EFs) to guide hiPS cells to their target. Applied EFs stimulated and guided migration of cultured hiPS cells toward the anode, with a stimulation threshold of <30 mV/mm; in three-dimensional (3D) culture hiPS cells remained stationary, whereas in an applied EF they migrated directionally. This is of significance as the therapeutic use of hiPS cells occurs in a 3D environment. EF exposure did not alter expression of the pluripotency markers SSEA-4 and Oct-4 in hiPS cells. We compared EF-directed migration (galvanotaxis) of hiPS cells and hES cells and found that hiPS cells showed greater sensitivity and directedness than those of hES cells in an EF, while hES cells migrated toward cathode. Rho-kinase (ROCK) inhibition, a method to aid expansion and survival of stem cells, significantly increased the motility, but reduced directionality of iPS cells in an EF by 70–80%. Thus, our study has revealed that physiological EF is an effective guidance cue for the migration of hiPS cells in either 2D or 3D environments and that will occur in a ROCK-dependent manner. Our current finding may lead to techniques for applying EFs in vivo to guide migration of transplanted stem cells

pcaGoPromoter - An R Package for Biological and Regulatory Interpretation of Principal Components in Genome-Wide Gene Expression Data

Analyzing data obtained from genome-wide gene expression experiments is challenging due to the quantity of variables, the need for multivariate analyses, and the demands of managing large amounts of data. Here we present the R package pcaGoPromoter, which facilitates the interpretation of genome-wide expression data and overcomes the aforementioned problems. In the first step, principal component analysis (PCA) is applied to survey any differences between experiments and possible groupings. The next step is the interpretation of the principal components with respect to both biological function and regulation by predicted transcription factor binding sites. The robustness of the results is evaluated using cross-validation, and illustrative plots of PCA scores and gene ontology terms are available. pcaGoPromoter works with any platform that uses gene symbols or Entrez IDs as probe identifiers. In addition, support for several popular Affymetrix GeneChip platforms is provided. To illustrate the features of the pcaGoPromoter package a serum stimulation experiment was performed and the genome-wide gene expression in the resulting samples was profiled using the Affymetrix Human Genome U133 Plus 2.0 chip. Array data were analyzed using pcaGoPromoter package tools, resulting in a clear separation of the experiments into three groups: controls, serum only and serum with inhibitor. Functional annotation of the axes in the PCA score plot showed the expected serum-promoted biological processes, e.g., cell cycle progression and the predicted involvement of expected transcription factors, including E2F. In addition, unexpected results, e.g., cholesterol synthesis in serum-depleted cells and NF-κB activation in inhibitor treated cells, were noted. In summary, the pcaGoPromoter R package provides a collection of tools for analyzing gene expression data. These tools give an overview of the input data via PCA, functional interpretation by gene ontology terms (biological processes), and an indication of the involvement of possible transcription factors

Insulin-Like Growth Factors Promote Vasculogenesis in Embryonic Stem Cells

The ability of embryonic stem cells to differentiate into endothelium and form functional blood vessels has been well established and can potentially be harnessed for therapeutic angiogenesis. However, after almost two decades of investigation in this field, limited knowledge exists for directing endothelial differentiation. A better understanding of the cellular mechanisms regulating vasculogenesis is required for the development of embryonic stem cell-based models and therapies. In this study, we elucidated the mechanistic role of insulin-like growth factors (IGF1 and 2) and IGF receptors (IGFR1 and 2) in endothelial differentiation using an embryonic stem cell embryoid body model. Both IGF1 or IGF2 predisposed embryonic stem to differentiate towards a mesodermal lineage, the endothelial precursor germ layer, as well as increased the generation of significantly more endothelial cells at later stages. Inhibition of IGFR1 signaling using neutralizing antibody or a pharmacological inhibitor, picropodophyllin, significantly reduced IGF-induced mesoderm and endothelial precursor cell formation. We confirmed that IGF-IGFR1 signaling stabilizes HIF1α and leads to up-regulation of VEGF during vasculogenesis in embryoid bodies. Understanding the mechanisms that are critical for vasculogenesis in various models will bring us one step closer to enabling cell based therapies for neovascularization

Decellularized Matrix from Tumorigenic Human Mesenchymal Stem Cells Promotes Neovascularization with Galectin-1 Dependent Endothelial Interaction

BACKGROUND: Acquisition of a blood supply is fundamental for extensive tumor growth. We recently described vascular heterogeneity in tumours derived from cell clones of a human mesenchymal stem cell (hMSC) strain (hMSC-TERT20) immortalized by retroviral vector mediated human telomerase (hTERT) gene expression. Histological analysis showed that cells of the most vascularized tumorigenic clone, -BD11 had a pericyte-like alpha smooth muscle actin (ASMA+) and CD146+ positive phenotype. Upon serum withdrawal in culture, -BD11 cells formed cord-like structures mimicking capillary morphogenesis. In contrast, cells of the poorly tumorigenic clone, -BC8 did not stain for ASMA, tumours were less vascularized and serum withdrawal in culture led to cell death. By exploring the heterogeneity in hMSC-TERT20 clones we aimed to understand molecular mechanisms by which mesenchymal stem cells may promote neovascularization. METHODOLOGY/PRINCIPAL FINDINGS: Quantitative qRT-PCR analysis revealed similar mRNA levels for genes encoding the angiogenic cytokines VEGF and Angiopoietin-1 in both clones. However, clone-BD11 produced a denser extracellular matrix that supported stable ex vivo capillary morphogenesis of human endothelial cells and promoted in vivo neovascularization. Proteomic characterization of the -BD11 decellularized matrix identified 50 extracellular angiogenic proteins, including galectin-1. siRNA knock down of galectin-1 expression abrogated the ex vivo interaction between decellularized -BD11 matrix and endothelial cells. More stable shRNA knock down of galectin-1 expression did not prevent -BD11 tumorigenesis, but greatly reduced endothelial migration into -BD11 cell xenografts. CONCLUSIONS: Decellularized hMSC matrix had significant angiogenic potential with at least 50 angiogenic cell surface and extracellular proteins, implicated in attracting endothelial cells, their adhesion and activation to form tubular structures. hMSC -BD11 surface galectin-1 expression was required to bring about matrix-endothelial interactions and for xenografted hMSC -BD11 cells to optimally recruit host vasculature

25th Annual Computational Neuroscience Meeting: CNS-2016

Abstracts of the 25th Annual Computational Neuroscience Meeting: CNS-2016 Seogwipo City, Jeju-do, South Korea. 2–7 July 201

Melatonin increases striatal dopaminergic function in 6-OHDA-lesioned rats.

A bi-weekly newsletter with University of Lethbridge campus news.PUBLISHED AT THE UNIVERSITY OF LETHBRIDGE FOR INTERNAL COMMUNICATION TUESDAY, November 9, 1971 Vol. IX No. 19 OFFICIAL NOTICES FINAL EXAMINATION TIMETABLES The 1971 Fall Final Examination Timetables are new posted on the Main Foyer bulletin board ( 6th floor ) and also on the bulletin board in front of the Registrar's Office ( 7th floor ). Please report any conflicts to the Registrar's Office by November 19, 1971. & & & & &_&_& COMPARATIVE ECONOMIC HISTORY LECTURE SERIES NO. 6 TOPIC: Russian Revolution: Origins and Reflections SPEAKER: DR. TED ORCHARD, History Department, The University of Lethbridge WHEN: TODAY, Tuesday, November 9, 1971, from 11:00 a.m. - 12:00 noon WHERE: Room D-519 EVERYONE AND ANYONE IS WELCOME!! UNIVERSITY SEMINAR Professor David Lai "The Physique of the Awakening Giant" WEDNESDAY, November 10, 1971, at 8:00 p.m. Lecture Theatre, West Campus (C-674) FOOD SERVICES - HOURS FOR THURSDAY, NOVEMBER ll, 1971. DINING ROOM: 10:00 a.m. - 6:00 p.m. HOT MEALS: 11:30 a.m. - 1:00 p.m. and 4:30 p.m. - 6:00 p.m. SHORT ORDER: 10:00 a.m. - 6:00 p.m. SNACK BAR: 6:00 p.m. - 10:30 p.m. ONLY. &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& <S_ <S_ &_ &_ <S <S <S_ 6 <S <S <S_ PLEASE BE ADVISED THAT SINCE THURSDAY, NOVEMBER 11, 1971, IS A STATUATORY HOLIDAY, THE UNIVERSITY WILL BE CLOSED. (over to 2) 2 - PHILOSOPHY SEMINAR Professor Stephan Kbmer of the University of Bristol and Yale University will read a paper entitled "On the Structure and Function of Scientific Theories on Monday the 15 th of November in Room D-630 of the Nest Campus from 4:00 - 6:00 p.m. Professor Khmer was born in 1913 in Czechoslovakia where he lived until 1939. He was educated at a classical gymnasium, at Charles ' University, Prague, and at Trinity Hall, Cambridge. After his war service in the Army he was appointed to a lectureship in 1946, and in 1952 to the chair of philosophy, both at the University of Bristol. At the present he holds a joint appointment at Bristol and Yale Universities. His writings include Conceptug I Thinking, The Philosophy of Mathematics, Kant, Experience and Theory, he has edited Observation and Interpretation in the Philosophy of Physics, he has written papers in various philosophical periodicals, and is presently serving as editor of the journal Ratio. Unfortunately Professor KHmer is not able to send us a copy of his paper in advance. Upcoming Fall 1971 Seminars Sponsored By The Chemistry Department, The University Of Lethbridge, Are Scheduled As Follows: - DR. CHRIS BENDER (The University of Lethbridge) "Photochemistry of Naphthabarrelenes" - DR. BOB KASTING (Canada Research Station) "Plant and Insect Chemistry" - DR. DOUGLAS DOLMAN (The University of Lethbridge) "Some Aspects of Enzyme Kinetics" ^iSfiiS(SiSiSiS^SiS<S<5iS^<S(SiSiS<S<S<5<SiS<SA'S^SSd November November December 19 26 3 STUDENT NOTICES ATTENTION - PRE-EDUCATION STUDENTS Pre-Education students who plan to are invited to complete application in Room B-822. &&&&&&&&&&&&&&&&&& enter forms & & & the Faculty of Education next semester now. Forms and information are available &&&&&&&&&&&&&&&&&&&&& The students representatives for the Department of Modern Languages are as follows: Representing French: Merril Roberts, two-year term Representing the other languages: Jennifer Jericho, one-year term Representing the other languages: Debbie Kemmet, two-year term For the remaining position (representing French, one-year term), there will be an election between Anne Wolters and Mark Ellingson, WEDNESDAY, November 10, 1971, at 12:00 noon in Room C-589. All students enrolled in any French course are eligible to vote, particularly those with majors in French. (Over to 3)- 3 - Would the following students please call into the Student Awards Office IMMEDIATELY: Mr. Brent Townsend Miss Christina Bexte Mr. John Chan Miss Jackie Ridley LIBRARY CARDS are now in. If you haven't picked yours up yet, please do so at the Circulation Desk of the Library. MISCELLANEOUS Im Schatten des Karakorum, one of a series of German films to be shown this semester, will be presented WEDNESDAY, November 10, 1971 at 1:00 p.m. in Room B-740C. ECONOMICS CLUB FALL 71 ETO The Economics Club is presenting its Fall ’71 ETO at the Henderson Lake Golf Club on WEDNESDAY, November 10, 1971, (November 11, 1971, is a holiday). Activities commence at 6:30 p.m. with a warm-up hour to be followed by dining and dancing. Tickets are $5.00 and are available from the Economics Club members and the Students' Society Office. Anyone in search of a good time is welcome to attend. Upcoming films presented by the Friendly Film Society are scheduled as follows: November 14 - "Elvira Madigan" - one of the most visually beautiful films ever made. November 21 - To be arranged. November 28 - "Monterey Pop" - an extraordinary film of the first rock festival with Jimi Hendrix, Janis Joplin, The Who, etc. - AT THE YATES - December 5 - Orsen Welles' film of Kifka's "The Trial" &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& R.C.M.P. EMPLOYMENT Representatives of the R.C.M.P. will be on campus TUESDAY, November 16, 1971, to contact preliminary employment interviews. If you are interested, you must reserve an interview time with Mrs. Albiston, Counselling Centre, by FRIDAY, November 12. TIMESHEETS FOR HOURLY EMPLOYEES SHOULD BE SUBMITTED ON NOVEMBER 12, 1971, FOR THE PERIOD CONCLUDING NOVEMBER 11, 1971. & & & &&&&&&&&&&&&&& _& (Over to 4)NOW IN THE BOOKSTORE!!! New from Cale's Canadian Collection: An Attempt to Reach Repulse Bay Backwoods of Canada Canadian Folk-Life and Folk-Lore Canadian Handbook and Tourist Guide Canadian Naturalist Canadian Savage Folk Forest Scenes and Incidents in the Wild Handbook of Indians of Canada Indian Treaties and Surrenders - 3 Volume Set Indians of Canada Letters from Canada Wm. Lyon Mackenzie - 2 Volume Set My Canadian Journal Pathfinding on Plain and Prairie Peace River Railways of Canada Smith's Canadian Gazetteers Songs of the Great Dominion Treaties of Canada with the Indians A Voyage to Hudson Bay Voyages and Travels of an Indian Interpreter Red Lights on the Prairies - James A. Gray The Winter Years - James A Gray The Boy From Winnipeg - James A. Gray PLUS a a large line of popular magazines and pocketbooks PLUS an exciting new collection of posters and parchments. PLEASE COME IN AND BROWSE AROUND!! We're open dpring the noon hours too