scholarly journals Natural variation in teosinte at the domestication locus teosinte branched1 (tb1)

2014 ◽  
Author(s):  
Laura Vann ◽  
Thomas Kono ◽  
Tanja Pyhäjärvi ◽  
Matthew B. Hufford ◽  
Jeffrey Ross-Ibarra
Keyword(s):  
Population Genetic ◽  
Potential Role ◽  
Sequence Data ◽  
Strong Association ◽  
Phenotypic Data ◽  
Maize Population ◽  
Teosinte Branched1 ◽  
Genetic Signatures ◽  
Future Work

The teosinte branched1 (tb1) gene is a major QTL controlling branching differences between maize and its wild progenitor, teosinte. The insertion of a transposable element (Hopscotch) upstream of tb1 is known to enhance the gene’s expression, causing reduced tillering in maize. Observations of the maize tb1 allele in teosinte and estimates of an insertion age of the Hopscotch that predates domestication led us to investigate its prevalence and potential role in teosinte. We assessed the prevalence of the Hopscotch element across an Americas-wide sample of 837 maize and teosinte individuals using a co-dominant PCR assay. Additionally, we calculated population genetic summaries using sequence data from a subset of individuals from four teosinte populations and collected phenotypic data using seed from a single teosinte population where Hopscotch was found segregating at high frequency. Genotyping results indicate the Hopscotch element is found in a number of teosinte populations and linkage disequilibrium near tb1 does not support recent introgression from maize. Population genetic signatures are consistent with selection on the tb1 locus revealing a potential ecological role, but a greenhouse experiment does not detect a strong association between the Hopscotch and tillering in teosinte. Our findings suggest the role of Hopscotch differs between maize and teosinte. Future work should assess tb1 expression levels in teosinte with and without the Hopscotch and more comprehensively phenotype teosinte to assess the ecological significance of the Hopscotch insertion and, more broadly, the tb1 locus in teosinte.

scholarly journals Natural variation in teosinte at the domestication locus teosinte branched1 (tb1)

2014 ◽  
Author(s):  
Laura Vann ◽  
Thomas Kono ◽  
Tanja Pyhäjärvi ◽  
Matthew B. Hufford ◽  
Jeffrey Ross-Ibarra
Keyword(s):  
Population Genetic ◽  
Potential Role ◽  
Sequence Data ◽  
Strong Association ◽  
Phenotypic Data ◽  
Maize Population ◽  
Teosinte Branched1 ◽  
Genetic Signatures ◽  
Future Work

The teosinte branched1 (tb1) gene is a major QTL controlling branching differences between maize and its wild progenitor, teosinte. The insertion of a transposable element (Hopscotch) upstream of tb1 is known to enhance the gene’s expression, causing reduced tillering in maize. Observations of the maize tb1 allele in teosinte and estimates of an insertion age of the Hopscotch that predates domestication led us to investigate its prevalence and potential role in teosinte. We assessed the prevalence of the Hopscotch element across an Americas-wide sample of 837 maize and teosinte individuals using a co-dominant PCR assay. Additionally, we calculated population genetic summaries using sequence data from a subset of individuals from four teosinte populations and collected phenotypic data using seed from a single teosinte population where Hopscotch was found segregating at high frequency. Genotyping results indicate the Hopscotch element is found in a number of teosinte populations and linkage disequilibrium near tb1 does not support recent introgression from maize. Population genetic signatures are consistent with selection on the tb1 locus revealing a potential ecological role, but a greenhouse experiment does not detect a strong association between the Hopscotch and tillering in teosinte. Our findings suggest the role of Hopscotch differs between maize and teosinte. Future work should assess tb1 expression levels in teosinte with and without the Hopscotch and more comprehensively phenotype teosinte to assess the ecological significance of the Hopscotch insertion and, more broadly, the tb1 locus in teosinte.

scholarly journals Natural variation in teosinte at the domestication locus teosinte branched1 (tb1)

2014 ◽  
Author(s):  
Laura Vann ◽  
Thomas Kono ◽  
Tanja Pyha ̈j ̈arvi ◽  
Matthew B Hufford ◽  
Jeffrey Ross-Ibarra
Keyword(s):  
Population Genetic ◽  
Potential Role ◽  
Strong Association ◽  
Pcr Assay ◽  
Phenotypic Data ◽  
Maize Population ◽  
Teosinte Branched1 ◽  
Genetic Signatures ◽  
Future Work

Premise of the study: The teosinte branched1 (tb1) gene is a major QTL controlling branching differences between maize and its wild progenitor, teosinte. The insertion of a transposable element (Hopscotch) upstream of tb1 is known to enhance the gene's expression, causing reduced tillering in maize. Observations of the maize tb1 allele in teosinte and estimates of an insertion age of the Hopscotch that predates domestication led us to investigate its prevalence and potential role in teosinte. Methods: Prevalence of the Hopscotch element was assessed across an Americas-wide sample of 837 maize and teosinte individuals using a codominant PCR assay. Population genetic summaries were calculated for a subset of individuals from four teosinte populations in central Mexico. Phenotypic data were also collected using seed from a single teosinte population where Hopscotch was found segregating at high frequency. Key results: Genotyping results indicate the Hopscotch element is found in a number of teosinte populations and linkage disequilibrium near tb1 does not support recent introgression from maize. Population genetic signatures are consistent with selection on this locus revealing a potential ecological role for Hopscotch in teosinte, but a greenhouse experiment does not detect a strong association between tb1 and tillering in teosinte. Conclusions: Our findings suggest the role of Hopscotch differs between maize and teosinte. Future work should assess tb1 expression levels in teosinte with and without the Hopscotch and more comprehensively phenotype teosinte to assess the ecological significance of the Hopscotch insertion and, more broadly, the tb1 locus in teosinte.

scholarly journals A PERFORATED MOBILE BREAKWATER FOR FIXED AND FLOATING APPLICATION

1966 ◽  
Vol 1 (10) ◽  
pp. 63 ◽  
Author(s):  
Wilbur Marks
Keyword(s):  
Potential Role ◽  
Front Wall ◽  
Test Results ◽  
Practical Application ◽  
Back Wall ◽  
Mooring Lines ◽  
Application Model ◽  
Perforated Breakwater ◽  
Future Work

A mobile breakwater concept based upon a perforated front wall and solid back wall is presented. The principles of energy dissipation by the system is discussed as well as the potential role of such a device within the framework of practical application. Model test results, comparing the perforated breakwater's response to waves with that of a caisson-type breakwater, are discussed. It is shown that the perforated breakwater experiences less force on the structure when it is fixed to the bottom and less force on the mooring lines when afloat than the caisson-type. However, the perforated breakwater is not more effective in reducing waves, for the conditions tested. Visual observations show that scouring is prevalent when the caisson-type is fixed to the bottom; there is no evidence of scouring with the perforated breakwater. Recommendations are made for future work.

scholarly journals Metagenomics reveals diet-specific specialization of bacterial communities in fungus gardens of grass- and dicot-cutter ants

2018 ◽  
Author(s):  
Lily Khadempour ◽  
Huan Fan ◽  
Ken Keefover-Ring ◽  
Camila Carlos ◽  
Nilson S. Nagamoto ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Bacterial Communities ◽  
Potential Role ◽  
Sequence Data ◽  
Bacterial Community Composition ◽  
Fungus Garden ◽  
Functional Profiles ◽  
Ant Fungus

AbstractLeaf-cutter ants in the genusAttaare dominant herbivores in the Neotropics. While most species ofAttacut dicots to incorporate into their fungus gardens, some species specialize on grasses. Here we examine the bacterial community associated with the fungus gardens of grass- and dicot-cutter ants to examine how changes in substrate input affect the bacterial community. We sequenced the metagenomes of 12Attafungus gardens, across four species of ants, with a total of 5.316 Gbp of sequence data. We show significant differences in the fungus garden bacterial community composition between dicot- and grass-cutter ants, with grass-cutter ants having lower diversity. Reflecting this difference in community composition, the bacterial functional profiles between the fungus gardens are significantly different. Specifically, grass-cutter ant fungus garden metagenomes are particularly enriched for genes responsible for amino acid, siderophore, and terpenoid biosynthesis while dicot-cutter ant fungus gardens metagenomes are enriched in genes involved in membrane transport. These differences in bacterial community composition and functional capacity show that different substrate inputs matter for fungus garden bacteria, and sheds light on the potential role of bacteria in mediating the ants’ transition to the use of a novel substrate.

scholarly journals The Role of High Density Lipoproteins in Thrombosis

2002 ◽  
Vol 2 ◽  
pp. 89-95 ◽  
Author(s):  
Marina Cuchel ◽  
Daniel J. Rader
Keyword(s):  
Potential Role ◽  
Strong Association ◽  
Coagulation Factors ◽  
Scientific Data ◽  
High Density ◽  
Plasma Lipoproteins ◽  
High Density Lipoproteins ◽  
Anionic Phospholipids ◽  
Lipids And Lipoproteins

Lipids and lipoproteins, as well as factors involved in hemostasis and thrombosis, play a central role in the pathogenesis of cardio- and cerebrovascular disease. In recent years it has become clear that a strong association exists between coagulation factors and plasma lipoproteins. Anionic phospholipids are necessary for the optimal activity of both pro- and anticoagulant enzymatic complexes. Cell membranes have traditionally been considered to provide the essential lipid-containing surfaces. However, in light of recent studies, plasma lipoproteins are also believed to provide appropriate surfaces to support coagulation. While triglyceride-rich lipoproteins and oxidized low-density lipoproteins are associated with a procoagulant profile, high-density lipoproteins (HDL) may have an anticoagulant effect. This paper reviews scientific data on the potential role of HDL as modulator of thrombotic processes.

Work characteristics and the emergence of a sustainable workforce: Do job design principles matter?

2006 ◽  
Vol 19 (2) ◽  
Author(s):  
Doris Fay ◽  
Alexandra Kamps
Keyword(s):  
Potential Role ◽  
Readiness To Change ◽  
Design Principles ◽  
Job Design ◽  
Work Characteristics ◽  
Work Related ◽  
Personal Initiative ◽  
Low Levels ◽  
Future Work

Work characteristics and the emergence of a sustainable workforce: Do job design principles matter? Work characteristics and the emergence of a sustainable workforce: Do job design principles matter? Doris Fay & Alexandra Kamps, Gedrag & Organisatie, Volume 19, June 2006, nr. 2, pp. 184. Today's organisations require a workforce with high levels of adaptability and flexibility, that is, a sustainable workforce. Drawing on the notion of socialization through work, this study looks at the potential role of job design for building a sustainable workforce. Drawing on data from 335 individuals from the new German countries, we tested whether levels of desirable attitudes and behaviours are associated with the application of Tayloristic design principles. Perceptions of work characteristics (job control, complexity, task completeness, prescription of one-best-way of doing the job) were used to create groups of work places that differed in degree of Taylorism. Comparison of jobs with high versus low levels of Taylorism showed that individuals with Tayloristic jobs had lower work-related self-efficacy, lower personal initiative, innovativity and readiness to change, and higher levels of control rejection and depression than individuals in less Tayloristic jobs. Implications for changing job demands and future work are discussed.

scholarly journals The Role of Hyperglycemia in Endometrial Cancer Pathogenesis

Cancers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1191 ◽  
Author(s):  
Frances L. Byrne ◽  
Amy R. Martin ◽  
Melidya Kosasih ◽  
Beth T. Caruana ◽  
Rhonda Farrell
Keyword(s):  
Endometrial Cancer ◽  
Cancer Progression ◽  
Potential Role ◽  
Strong Association ◽  
Epidemiological Evidence ◽  
Glucose Lowering ◽  
Cancer Pathogenesis ◽  
Obesity And Cancer

Endometrial cancer is one of the most common cancers in women worldwide and its incidence is increasing. Epidemiological evidence shows a strong association between endometrial cancer and obesity, and multiple mechanisms linking obesity and cancer progression have been described. However, it remains unclear which factors are the main drivers of endometrial cancer development. Hyperglycemia and type 2 diabetes mellitus are common co-morbidities of obesity, and there is evidence that hyperglycemia is a risk factor for endometrial cancer independent of obesity. This review aims to explore the association between hyperglycemia and endometrial cancer, and discuss the evidence supporting a role for increased glucose metabolism in endometrial cancer and how this phenotype may contribute to endometrial cancer growth and progression. Finally, the potential role of blood glucose lowering strategies, including drugs and bariatric surgery, for the treatment of this malignancy will be discussed.

Potential role of intraspecific and interspecific cloning in the conservation of wild mammals

Zygote ◽  
2019 ◽  
Vol 27 (3) ◽  
pp. 111-117 ◽  
Author(s):  
Alana Azevedo Borges ◽  
Alexsandra Fernandes Pereira
Keyword(s):  
Somatic Cell ◽  
Embryo Development ◽  
Potential Role ◽  
Donor Cell ◽  
Cell Nuclei ◽  
Wild Mammals ◽  
Donor Cells ◽  
Cell Banks ◽  
Future Work

SummaryIntraspecific and interspecific cloning via somatic cell nuclear transfer (iSCNT) is a biotechnique with great possibilities for wild mammals because it allows the maintenance of biodiversity by recovering species, nuclear reprogramming for the production of pluripotency-induced cells, and studies related to embryonic development. Nevertheless, many areas in cloning, especially those associated with wild mammals, are still in question because of the difficulty in obtaining cytoplasmic donor cells (or cytoplasts). Conversely, donor cell nuclei (or karyoplasts) are widely obtained from the skin of living or post-mortem individuals and often maintained in somatic cell banks. Moreover, the creation of karyoplast–cytoplast complexes by fusion followed by activation and embryo development is one of the most difficult steps that requires further clarification to avoid genetic failures. Although difficult, cloning different species, such as wild carnivores and ungulates, can be successful via iSCNT with embryo development and the birth of offspring. Thus, novel research in the area that contributes to the conservation of biodiversity and knowledge of the physiology of species continues. The present review presents the failures and successes that occurred with the application of the technique in wild mammals, with the goal of helping future work on cloning via iSCNT.

scholarly journals Synthesis of geological and comparative phylogeographic data point to climate, not mountain uplift, as driver of divergence across the Eastern Andean Cordillera

2020 ◽  
Author(s):  
Erika Rodríguez-Muñoz ◽  
Camilo Montes ◽  
Andrew J. Crawford
Keyword(s):  
Life History ◽  
Potential Role ◽  
Linear Models ◽  
Sequence Data ◽  
Divergence Time ◽  
Climatic Conditions ◽  
Divergence Times ◽  
Geological Evidence ◽  
Andean Cordillera

AbstractAimTo evaluate the potential role of the orogeny of the Eastern Cordillera (EC) of the Colombian Andes and the Mérida Andes (MA) of Venezuela as drivers of vicariance between populations of 37 tetrapod lineages co-distributed on both flanks, through geological reconstruction and comparative phylogeographic analyses.LocationNorthwestern South AmericaMethodsWe first reviewed and synthesized published geological data on the timing of uplift for the EC-MA. We then combined newly generated mitochondrial DNA sequence data with published datasets to create a comparative phylogeographic dataset for 37 independent tetrapod lineages. We reconstructed time-calibrated molecular phylogenies for each lineage under Bayesian inference to estimate divergence times between lineages located East and West of the Andes. We performed a comparative phylogeographic analysis of all lineages within each class of tetrapod using hierarchical approximate Bayesian computation (hABC) to test for synchronous vicariance across the EC-MA. To evaluate the potential role of life history in explaining variation in divergence times among lineages, we evaluated 13 general linear models (GLM) containing up to six variables each (maximum elevation, range size, body length, thermoregulation, type of dispersal, and taxonomic class).ResultsOur synthesis of geological evidence suggested that the EC-MA reached significant heights by 38–33 million years ago (Ma) along most of its length, and we reject the oft-cited date of 2–5 Ma. Based on mtDNA divergence from 37 lineages, however, the median estimated divergence time across the EC-MA was 3.26 Ma (SE = 2.84) in amphibians, 2.58 Ma (SE = 1.81) in birds, 2.99 Ma (SE = 4.68) in reptiles and 1.43 Ma (SE = 1.23) in mammals. Using Bayes Factors, the hypothesis for a single temporal divergence interval containing synchronous divergence events was supported for mammals and but not supported for amphibians, non-avian reptiles, or birds. Among the six life-history variables tested, only thermoregulation successfully explained variation in divergence times (minimum AICc, R2 0.10), with homeotherms showing more recent divergence relative to poikilotherms.Main conclusionsOur results reject the hypothesis of the rise Andean Cordillera as driver of vicariance of lowland population because divergence dates are too recent and too asynchronous. We discuss alternative explanations, including dispersal through mountain passes, and suggest that changes in the climatic conditions during the Pliocene and Pleistocene interacted with tetrapod physiology, promoting older divergences in amphibians and reptiles relative to mammals and birds on an already established orogen.

POPDC proteins and cardiac function

2019 ◽  
Vol 47 (5) ◽  
pp. 1393-1404 ◽  
Author(s):  
Thomas Brand
Keyword(s):  
Potential Role ◽  
Striated Muscle ◽  
Short Review ◽  
Effector Proteins ◽  
Muscle Disease ◽  
Disease Genes ◽  
Protein Protein Interaction ◽  
Interaction Partners ◽  
And Function

Abstract The Popeye domain-containing gene family encodes a novel class of cAMP effector proteins in striated muscle tissue. In this short review, we first introduce the protein family and discuss their structure and function with an emphasis on their role in cyclic AMP signalling. Another focus of this review is the recently discovered role of POPDC genes as striated muscle disease genes, which have been associated with cardiac arrhythmia and muscular dystrophy. The pathological phenotypes observed in patients will be compared with phenotypes present in null and knockin mutations in zebrafish and mouse. A number of protein–protein interaction partners have been discovered and the potential role of POPDC proteins to control the subcellular localization and function of these interacting proteins will be discussed. Finally, we outline several areas, where research is urgently needed.

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