1
|
Lai Polo SH, Saravia-Butler AM, Boyko V, Dinh MT, Chen YC, Fogle H, Reinsch SS, Ray S, Chakravarty K, Marcu O, Chen RB, Costes SV, Galazka JM. RNAseq Analysis of Rodent Spaceflight Experiments Is Confounded by Sample Collection Techniques. iScience 2020; 23:101733. [PMID: 33376967 PMCID: PMC7756143 DOI: 10.1016/j.isci.2020.101733] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/04/2020] [Accepted: 10/22/2020] [Indexed: 02/07/2023] Open
Abstract
To understand the physiological changes that occur in response to spaceflight, mice are transported to the International Space Station (ISS) and housed for variable periods of time before euthanasia on-orbit or return to Earth. Sample collection under such difficult conditions introduces confounding factors that need to be identified and addressed. We found large changes in the transcriptome of mouse tissues dissected and preserved on-orbit compared with tissues from mice euthanized on-orbit, preserved, and dissected after return to Earth. Changes due to preservation method eclipsed those between flight and ground samples, making it difficult to identify spaceflight-specific changes. Follow-on experiments to interrogate the roles of euthanasia methods, tissue and carcass preservation protocols, and library preparation methods suggested that differences due to preservation protocols are exacerbated when coupled with polyA selection. This has important implications for the interpretation of existing datasets and the design of future experiments. Experimentation is necessary to understand how organisms respond to space Specialized protocols are used for preserving biological samples on the ISS RNAseq datasets are impacted by preservation protocols used on the ISS Impacts can be alleviated with improved carcass preservation protocols
Collapse
Affiliation(s)
- San-Huei Lai Polo
- KBR, NASA Ames Research Center, Moffett Field, CA 94035, USA.,NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - Amanda M Saravia-Butler
- NASA Ames Research Center, Moffett Field, CA 94035, USA.,Logyx, LLC, Mountain View, CA 94043, USA
| | - Valery Boyko
- NASA Ames Research Center, Moffett Field, CA 94035, USA.,The Bionetics Corporation, NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - Marie T Dinh
- NASA Ames Research Center, Moffett Field, CA 94035, USA.,Logyx, LLC, Mountain View, CA 94043, USA
| | - Yi-Chun Chen
- KBR, NASA Ames Research Center, Moffett Field, CA 94035, USA.,NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - Homer Fogle
- NASA Ames Research Center, Moffett Field, CA 94035, USA.,The Bionetics Corporation, NASA Ames Research Center, Moffett Field, CA 94035, USA
| | | | - Shayoni Ray
- NGM Biopharmaceuticals, South San Francisco, CA 94080, USA
| | | | - Oana Marcu
- Carl Sagan Center, SETI Institute, Mountain View, CA 94043, USA
| | - Rick B Chen
- KBR, NASA Ames Research Center, Moffett Field, CA 94035, USA.,NASA Ames Research Center, Moffett Field, CA 94035, USA
| | | | | |
Collapse
|
2
|
Orton L, de Cuevas RA, Stojanovski K, Gamella JF, Greenfields M, La Parra D, Marcu O, Matras Y, Donert C, Frost D, Robinson J, Rosenhaft E, Salway S, Sheard S, Such E, Taylor-Robinson D, Whitehead M. Roma populations and health inequalities: a new perspective. Int J Hum Rights Healthc 2019; 12:319-327. [PMID: 32082612 PMCID: PMC7032950 DOI: 10.1108/ijhrh-01-2019-0004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Purpose The purpose of this paper is to explore the emergence of "Roma health and wellbeing" as a focus of attention in European research and in policy and the possible detrimental consequences of action founded on a generic representation of "Roma health." Design/methodology/approach Based on discussions with and research conducted by scholars who work directly with Roma communities across European regions from a wide range of academic disciplines it suggests how future research might inform: a more nuanced understanding of the causes of poor health and wellbeing among diverse Roma populations and; actions that may have greater potential to improve the health and wellbeing among these populations. Findings In summary, the authors promote three types of research: first critical analyses that unpick the implications of current and past representations of "Roma" and "Roma health." Second, applied participatory research that meaningfully involves people from specific self-defined Roma populations to identify important issues for their health and wellbeing. Third, learning about processes that might impact on the health and wellbeing of Roma populations from research with other populations in similarly excluded situations. Originality/value The authors provide a multidisciplinary perspective to inform research that does not perpetuate further alienation and prejudice, but promotes urgent action to redress the social and health injustices experienced by diverse Roma populations across Europe.
Collapse
Affiliation(s)
- Lois Orton
- Department of Public Health and Policy, University of Liverpool, Liverpool, UK
| | | | | | - Juan F Gamella
- Department of Social Anthropology, University of Granada, Granada, Spain
| | | | - Daniel La Parra
- Department of Sociology, University of Alicante, Alicante, Spain
| | - Oana Marcu
- Department of Sociology, Catholic University of the Sacred Heart, Milan, Italy
| | - Yaron Matras
- Linguistics and English Language, University of Manchester, Manchester, UK
| | - Celia Donert
- Department of Public Health and Policy, University of Liverpool, Liverpool, UK
| | - Diane Frost
- Department of Public Health and Policy, University of Liverpool, Liverpool, UK
| | - Jude Robinson
- School of Social and Political Sciences, University of Glasgow, Glasgow, UK
| | - Eve Rosenhaft
- Department of Public Health and Policy, University of Liverpool, Liverpool, UK
| | - Sarah Salway
- Sociological Studies, University of Sheffield, Sheffield, UK
| | - Sally Sheard
- Department of Public Health and Policy, University of Liverpool, Liverpool, UK
| | - Elizabeth Such
- School of Health and Related Research, University of Sheffield, Sheffield, UK
| | | | - Margaret Whitehead
- Department of Public Health and Policy, University of Liverpool, Liverpool, UK
| |
Collapse
|
3
|
Parra M, Jung J, Boone TD, Tran L, Blaber EA, Brown M, Chin M, Chinn T, Cohen J, Doebler R, Hoang D, Hyde E, Lera M, Luzod LT, Mallinson M, Marcu O, Mohamedaly Y, Ricco AJ, Rubins K, Sgarlato GD, Talavera RO, Tong P, Uribe E, Williams J, Wu D, Yousuf R, Richey CS, Schonfeld J, Almeida EAC. Microgravity validation of a novel system for RNA isolation and multiplex quantitative real time PCR analysis of gene expression on the International Space Station. PLoS One 2017; 12:e0183480. [PMID: 28877184 PMCID: PMC5587110 DOI: 10.1371/journal.pone.0183480] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 08/04/2017] [Indexed: 11/29/2022] Open
Abstract
The International Space Station (ISS) National Laboratory is dedicated to studying the effects of space on life and physical systems, and to developing new science and technologies for space exploration. A key aspect of achieving these goals is to operate the ISS National Lab more like an Earth-based laboratory, conducting complex end-to-end experimentation, not limited to simple microgravity exposure. Towards that end NASA developed a novel suite of molecular biology laboratory tools, reagents, and methods, named WetLab-2, uniquely designed to operate in microgravity, and to process biological samples for real-time gene expression analysis on-orbit. This includes a novel fluidic RNA Sample Preparation Module and fluid transfer devices, all-in-one lyophilized PCR assays, centrifuge, and a real-time PCR thermal cycler. Here we describe the results from the WetLab-2 validation experiments conducted in microgravity during ISS increment 47/SPX-8. Specifically, quantitative PCR was performed on a concentration series of DNA calibration standards, and Reverse Transcriptase-quantitative PCR was conducted on RNA extracted and purified on-orbit from frozen Escherichia coli and mouse liver tissue. Cycle threshold (Ct) values and PCR efficiencies obtained on-orbit from DNA standards were similar to Earth (1 g) controls. Also, on-orbit multiplex analysis of gene expression from bacterial cells and mammalian tissue RNA samples was successfully conducted in about 3 h, with data transmitted within 2 h of experiment completion. Thermal cycling in microgravity resulted in the trapping of gas bubbles inside septa cap assay tubes, causing small but measurable increases in Ct curve noise and variability. Bubble formation was successfully suppressed in a rapid follow-up on-orbit experiment using standard caps to pressurize PCR tubes and reduce gas release during heating cycles. The WetLab-2 facility now provides a novel operational on-orbit research capability for molecular biology and demonstrates the feasibility of more complex wet bench experiments in the ISS National Lab environment.
Collapse
Affiliation(s)
- Macarena Parra
- Space Biosciences Research Branch, NASA Ames Research Center, Moffett Field, California, United States of America
| | - Jimmy Jung
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- KBRWyle, Mountain View, California, United States of America
| | - Travis D. Boone
- Office of the Director, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Luan Tran
- Space Biosciences Research Branch, NASA Ames Research Center, Moffett Field, California, United States of America
- KBRWyle, Mountain View, California, United States of America
| | - Elizabeth A. Blaber
- Space Biosciences Research Branch, NASA Ames Research Center, Moffett Field, California, United States of America
- Universities Space Research Association, Mountain View, California, United States of America
| | - Mark Brown
- Applications Development, Claremont Biosolutions, Upland, California, United States of America
| | - Matthew Chin
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Tori Chinn
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Jacob Cohen
- Office of the Director, NASA Ames Research Center, Moffett Field, California, United States of America
| | - Robert Doebler
- Applications Development, Claremont Biosolutions, Upland, California, United States of America
| | - Dzung Hoang
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Elizabeth Hyde
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Matthew Lera
- KBRWyle, Mountain View, California, United States of America
- Flight Systems Implementation Branch, NASA Ames Research Center, Moffett Field, California, United States of America
| | - Louie T. Luzod
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
| | - Mark Mallinson
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
| | - Oana Marcu
- Space Biosciences Research Branch, NASA Ames Research Center, Moffett Field, California, United States of America
- KBRWyle, Mountain View, California, United States of America
| | - Youssef Mohamedaly
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Antonio J. Ricco
- Mission Design Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Stanford University, Palo Alto, California, United States of America
| | - Kathleen Rubins
- NASA Astronaut Corps, NASA Johnson Space Center, Houston, Texas, United States of America
| | - Gregory D. Sgarlato
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- KBRWyle, Mountain View, California, United States of America
| | - Rafael O. Talavera
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Peter Tong
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
- Millenium Engineering & Integration Co, Mountain View, California, United States of America
| | - Eddie Uribe
- Universities Space Research Association, Mountain View, California, United States of America
| | - Jeffrey Williams
- NASA Astronaut Corps, NASA Johnson Space Center, Houston, Texas, United States of America
| | - Diana Wu
- KBRWyle, Mountain View, California, United States of America
- Mission Design Division, NASA Ames Research Center, Moffett Field, California, United States of America
| | - Rukhsana Yousuf
- Space Biosciences Research Branch, NASA Ames Research Center, Moffett Field, California, United States of America
- KBRWyle, Mountain View, California, United States of America
| | - Charles S. Richey
- Universities Space Research Association, Mountain View, California, United States of America
| | - Julie Schonfeld
- Engineering Systems Division, NASA Ames Research Center, Moffett Field, California, United States of America
| | - Eduardo A. C. Almeida
- Space Biosciences Research Branch, NASA Ames Research Center, Moffett Field, California, United States of America
- * E-mail:
| |
Collapse
|
4
|
Nemčovská E, Garabášová M, Kállayová D, Majdan M, Rafajdus M, Rusnák M, Grendová K, Počrvina GO, Marcu O, Savova S, Vassileva S, Marinković S, Popović A, Stanković J, Stošić D, Karali A. Financial literacy for Roma – How to determine health of Roma communities? Eur J Public Health 2016. [DOI: 10.1093/eurpub/ckw174.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
5
|
Brann M, Marcu O. The Role of Copper in the Oxidative Stress Response of
Chlamydomonas reinhardtii
to heat shock. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.887.27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Oana Marcu
- Space Science Exobiology NASA Ames Research CenterMoffett FieldCAUnited States
| |
Collapse
|
6
|
Chan KL, Inan O, Bhattacharya S, Marcu O. Estimating the speed of Drosophila locomotion using an automated behavior detection and analysis system. Fly (Austin) 2014; 6:205-10. [DOI: 10.4161/fly.20987] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
|
7
|
Inan OT, Marcu O, Sanchez ME, Bhattacharya S, Kovacs GTA. A portable system for monitoring the behavioral activity of Drosophila. J Neurosci Methods 2011; 202:45-52. [PMID: 21907735 DOI: 10.1016/j.jneumeth.2011.08.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 08/05/2011] [Accepted: 08/25/2011] [Indexed: 12/29/2022]
Abstract
We describe a low-cost system for monitoring the behavioral activity of the fruit fly, Drosophila melanogaster. The system is readily adaptable to one or more cameras for simultaneous recordings of behavior from different angles and can be used for monitoring multiple individuals in a population at the same time. Signal processing allows discriminating between active and inactive periods during locomotion or flying, and quantification of subtler movements related to changes in position of the wings or legs. The recordings can be taken continuously over long periods of time and can thus provide information about the dynamics of a population. The system was used to monitor responses to caffeine, changes in temperature and g-force, and activity in a variable size population.
Collapse
Affiliation(s)
- Omer T Inan
- Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA
| | | | | | | | | |
Collapse
|
8
|
Marcu O, Lera MP, Sanchez ME, Levic E, Higgins LA, Shmygelska A, Fahlen TF, Nichol H, Bhattacharya S. Innate immune responses of Drosophila melanogaster are altered by spaceflight. PLoS One 2011; 6:e15361. [PMID: 21264297 PMCID: PMC3019151 DOI: 10.1371/journal.pone.0015361] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 11/11/2010] [Indexed: 01/20/2023] Open
Abstract
Alterations and impairment of immune responses in humans present a health risk for space exploration missions. The molecular mechanisms underpinning innate immune defense can be confounded by the complexity of the acquired immune system of humans. Drosophila (fruit fly) innate immunity is simpler, and shares many similarities with human innate immunity at the level of molecular and genetic pathways. The goals of this study were to elucidate fundamental immune processes in Drosophila affected by spaceflight and to measure host-pathogen responses post-flight. Five containers, each containing ten female and five male fruit flies, were housed and bred on the space shuttle (average orbit altitude of 330.35 km) for 12 days and 18.5 hours. A new generation of flies was reared in microgravity. In larvae, the immune system was examined by analyzing plasmatocyte number and activity in culture. In adults, the induced immune responses were analyzed by bacterial clearance and quantitative real-time polymerase chain reaction (qPCR) of selected genes following infection with E. coli. The RNA levels of relevant immune pathway genes were determined in both larvae and adults by microarray analysis. The ability of larval plasmatocytes to phagocytose E. coli in culture was attenuated following spaceflight, and in parallel, the expression of genes involved in cell maturation was downregulated. In addition, the level of constitutive expression of pattern recognition receptors and opsonins that specifically recognize bacteria, and of lysozymes, antimicrobial peptide (AMP) pathway and immune stress genes, hallmarks of humoral immunity, were also reduced in larvae. In adults, the efficiency of bacterial clearance measured in vivo following a systemic infection with E. coli post-flight, remained robust. We show that spaceflight altered both cellular and humoral immune responses in Drosophila and that the disruption occurs at multiple interacting pathways.
Collapse
Affiliation(s)
- Oana Marcu
- Space Biosciences Division, NASA Ames Research Center, Mountain View, California, United States of America
- Carl Sagan Center, SETI Institute, Mountain View, California, United States of America
| | - Matthew P. Lera
- Space Biosciences Division, NASA Ames Research Center, Mountain View, California, United States of America
- Lockheed Martin Exploration & Science, NASA Ames Research Center, Mountain View, California, United States of America
| | - Max E. Sanchez
- Lockheed Martin Exploration & Science, NASA Ames Research Center, Mountain View, California, United States of America
| | - Edina Levic
- Space Biosciences Division, NASA Ames Research Center, Mountain View, California, United States of America
| | - Laura A. Higgins
- Space Biosciences Division, NASA Ames Research Center, Mountain View, California, United States of America
| | - Alena Shmygelska
- Space Biosciences Division, NASA Ames Research Center, Mountain View, California, United States of America
- Silicon Valley Campus of Carnegie Mellon University, NASA Ames Research Center, Mountain View, California, United States of America
| | - Thomas F. Fahlen
- Lockheed Martin Exploration & Science, NASA Ames Research Center, Mountain View, California, United States of America
| | - Helen Nichol
- Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Sharmila Bhattacharya
- Space Biosciences Division, NASA Ames Research Center, Mountain View, California, United States of America
- * E-mail:
| |
Collapse
|
9
|
Inan O, Etemadi M, Sanchez M, Marcu O, Bhattacharya S, Kovacs G. A Miniaturized Video System for Monitoring the Locomotor Activity of WalkingDrosophila Melanogasterin Space and Terrestrial Settings. IEEE Trans Biomed Eng 2009; 56:522-4. [DOI: 10.1109/tbme.2008.2006018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
10
|
Johnson KG, Tenney AP, Ghose A, Duckworth AM, Higashi ME, Parfitt K, Marcu O, Heslip TR, Marsh JL, Schwarz TL, Flanagan JG, Van Vactor D. The HSPGs Syndecan and Dallylike bind the receptor phosphatase LAR and exert distinct effects on synaptic development. Neuron 2006; 49:517-31. [PMID: 16476662 DOI: 10.1016/j.neuron.2006.01.026] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2005] [Revised: 12/07/2005] [Accepted: 01/23/2006] [Indexed: 12/28/2022]
Abstract
The formation and plasticity of synaptic connections rely on regulatory interactions between pre- and postsynaptic cells. We show that the Drosophila heparan sulfate proteoglycans (HSPGs) Syndecan (Sdc) and Dallylike (Dlp) are synaptic proteins necessary to control distinct aspects of synaptic biology. Sdc promotes the growth of presynaptic terminals, whereas Dlp regulates active zone form and function. Both Sdc and Dlp bind at high affinity to the protein tyrosine phosphatase LAR, a conserved receptor that controls both NMJ growth and active zone morphogenesis. These data and double mutant assays showing a requirement of LAR for actions of both HSPGs lead to a model in which presynaptic LAR is under complex control, with Sdc promoting and Dlp inhibiting LAR in order to control synapse morphogenesis and function.
Collapse
Affiliation(s)
- Karl G Johnson
- Department of Cell Biology and Program in Neuroscience, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Nedelcu AM, Marcu O, Michod RE. Sex as a response to oxidative stress: a twofold increase in cellular reactive oxygen species activates sex genes. Proc Biol Sci 2004; 271:1591-6. [PMID: 15306305 PMCID: PMC1691771 DOI: 10.1098/rspb.2004.2747] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Organisms are constantly subjected to factors that can alter the cellular redox balance and result in the formation of a series of highly reactive molecules known as reactive oxygen species (ROS). As ROS can be damaging to biological structures, cells evolved a series of mechanisms (e.g. cell-cycle arrest, programmed cell death) to respond to high levels of ROS (i.e. oxidative stress). Recently, we presented evidence that in a facultatively sexual lineage--the multicellular green alga Volvox carteri--sex is an additional response to increased levels of stress, and probably ROS and DNA damage. Here we show that, in V. carteri, (i) sex is triggered by an approximately twofold increase in the level of cellular ROS (induced either by the natural sex-inducing stress, namely heat, or by blocking the mitochondrial electron transport chain with antimycin A), and (ii) ROS are responsible for the activation of sex genes. As most types of stress result in the overproduction of ROS, we believe that our findings will prove to extend to other facultatively sexual lineages, which could be indicative of the ancestral role of sex as an adaptive response to stress and ROS-induced DNA damage.
Collapse
Affiliation(s)
- Aurora M Nedelcu
- Department of Biology, University of New Brunswick, Fredericton, Canada.
| | | | | |
Collapse
|
12
|
Marcu O, Stathakis DG, Marsh JL. Assignment of the UGDH locus encoding UDP-glucose dehydrogenase to human chromosome band 4p15.1 by radiation hybrid mapping. Cytogenet Cell Genet 1999; 86:244-5. [PMID: 10575217 DOI: 10.1159/000015350] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- O Marcu
- Department of Developmental Biology, Epidemiology Division, University of California, Irvine CA, USA
| | | | | |
Collapse
|
13
|
Marcu O, Locke M. The origin, transport and cleavage of the molt-associated cuticular protein CECP22 from Calpodes ethlius (Lepidoptera, Hesperiidae). J Insect Physiol 1999; 45:861-870. [PMID: 12770299 DOI: 10.1016/s0022-1910(99)00070-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
CECP22 (Calpodes ethlius Cuticular Protein 22 kDa) is a molt associated protein found in the cuticle of C. ethlius larvae and pupae. The mRNA for the CECP22 cuticular protein is expressed in the epidermis and fat body during the intermolt. The protein itself accumulates in intermolt hemolymph, but at molting, when the cuticle is being digested, it is also found in the cuticle of surface integument, tracheae, foregut and hindgut and in the molting fluid. CECP22 exists in two forms. The large form (19.17 kDa, pI 6.2) becomes smaller (16.1 kDa, pI 7.4) by cleavage at the proteolytic cleavage site (position 170) with amidation of the C-terminal. The small, more basic peptide, appears only at molting, first in the cuticle and then in the molting fluid. It is presumed to be the active form of an amidase involved in the earliest stages of cuticle degradation. The inactive form accumulates in the hemolymph during the long intermolt and probably represents an abundant source of precursor enzyme that can be provided to all cuticle containing organs for a precise initiation of cuticle degradation.
Collapse
Affiliation(s)
- O Marcu
- Department of Zoology, University of Western Ontario, London, Canada
| | | |
Collapse
|
14
|
Abstract
A 22 kDa peptide was purified from prepupal cuticles of 5th instar Calpodes ethlius caterpillars. It was absent earlier in the stadium and from the egg and adult, i.e. it is related to cuticle turnover rather than cuticle structure. It was present at larval and metamorphic moults, showing that it is related to moulting not just metamorphosis. The cDNA corresponding to the 22 kDa peptide was isolated by antibody screening of an epidermal cDNA expression library. Hybridization to Calpodes genomic DNA showed that the gene was present as a single copy. The deduced amino acid sequence is not like any of the sequences of cuticular structural proteins that have been published, but has a 47 amino acid sequence similar to bacteriophage T7 N-acetylmuramoyl-L-alanine amidase (34% identical, 51% similar). The amino acid sequence, the timing of expression in development, and the similarity between the substrate of the bacteriophage amidase and components of insect cuticle, all suggest that the 22 kDa protein may have a role in cleaving chitin-peptide bonds as a prerequisite for digestion of the cuticle by chitinases and proteases.
Collapse
Affiliation(s)
- O Marcu
- Department of Zoology, University of Western Ontario, London, Canada
| | | |
Collapse
|