scholarly journals Evolution of cold acclimation in temperate grasses (Pooideae)

2017 ◽  
Author(s):  
Marian Schubert ◽  
Lars Grønvold ◽  
Simen R. Sandve ◽  
Torgeir R. Hvidsten ◽  
Siri Fjellheim

AbstractIn the past 50 million years climate cooling has triggered the expansion of temperate biomes. During this period, many extant plant lineages in temperate biomes evolved from tropical ancestors and adapted to seasonality and cool conditions. Among the Poaceae (grass family), one of the subfamilies that successfully shifted from tropical to temperate biomes is the Pooideae (temperate grasses). Subfamily Pooideae contains the most important crops cultivated in the temperate regions including wheat (Triticum aestivum) and barley (Hordeum vulgare). Due to the need of well-adapted cultivars, extensive research has produced a large body of knowledge about the mechanisms underlying cold adaptation in cultivated Pooideae species. Especially cold acclimation, a process which increases the frost tolerance during a period of non-freezing cold, plays an important role. Because cold adaptation is largely unexplored in lineages that diverged early in the evolution of the Pooideae, little is known about the evolutionary history of cold acclimation in the Pooideae. Here we test if several species of early diverging lineages exhibit increased frost tolerance after a period of cold acclimation. We further investigate the conservation of five well-studied gene families that are known to be involved in the cold acclimation of Pooideae crop species. Our results indicate that cold acclimation exists in early diverging lineages, but that genes involved in regulation of cold acclimation are not conserved. The investigated gene families show signs of lineage-specific evolution and support the hypothesis that gene family expansion is an important mechanism in adaptive evolution.

2020 ◽  
Vol 23 (8) ◽  
pp. 958-963 ◽  
Author(s):  
L. S. Samarina ◽  
L. S. Malyukova ◽  
M. V. Gvasaliya ◽  
A. M. Efremov ◽  
V. I. Malyarovskaya ◽  
...  

The article reviews the latest studies showing the diversity of genetic mechanisms and gene families underlying the increased cold and frost tolerance of tea and other plant species. It has been shown that cell responses to chilling (0…+15°C) and freezing (< 0°C) are not the same and gene expression under cold stress is genotype-specific. In recent decades, progress has been made in understanding the genetic mechanisms underlying the cold response of plants – ICE1 (inducer of CBF expression 1), CBF (C-repeat-binding factor), COR (cold-regulated genes) pathways and signaling have been discovered. The ICE, CBF and DHN gene groups play a key role in the cold acclimation of the tea plant. The accumulation of CBF transcripts occurs after 15 min of chilling induction, and longer cold stress leads to accumulation of CBF transcripts. It is shown that the transcripts of the CsDHN1, CsDHN2 and CsDHN3 genes accumulate at a higher level in resistant genotypes of tea in comparison with susceptible cultivars during freezing. CBF-independent pathways include genes involved in metabolism and transcription factors such as HSFC1, ZAT12, CZF1, PLD (phospholipase D), WRKY, HD-Zip, CsLEA, LOX, NAC, HSP, which are widely distributed in plants and are involved in the basic mechanisms of tea resistance to cold and frost. The most recent studies show an important role of miRNA in the mechanisms of response to chilling and freezing in tea. The data obtained on different plant species may correlate with the mechanisms of frost tolerance of tea and are the basis for future studies of the signaling pathways of response to cold in the tea plant. The results of the research emphasize the need to further explore the ways in which various genes regulate the tolerance of tea to cold stress to find the molecular markers of frost tolerance.


Author(s):  
Stephen Verderber

The interdisciplinary field of person-environment relations has, from its origins, addressed the transactional relationship between human behavior and the built environment. This body of knowledge has been based upon qualitative and quantitative assessment of phenomena in the “real world.” This knowledge base has been instrumental in advancing the quality of real, physical environments globally at various scales of inquiry and with myriad user/client constituencies. By contrast, scant attention has been devoted to using simulation as a means to examine and represent person-environment transactions and how what is learned can be applied. The present discussion posits that press-competency theory, with related aspects drawn from functionalist-evolutionary theory, can together function to help us learn of how the medium of film can yield further insights to person-environment (P-E) transactions in the real world. Sampling, combined with extemporary behavior setting analysis, provide the basis for this analysis of healthcare settings as expressed throughout the history of cinema. This method can be of significant aid in examining P-E transactions across diverse historical periods, building types and places, healthcare and otherwise, otherwise logistically, geographically, or temporally unattainable in real time and space.


2003 ◽  
Vol 1 (1) ◽  
pp. 39-76 ◽  
Author(s):  
Graham Connah ◽  
S.G.H. Daniels

New archaeological research in Borno by the Johann-Wolfgang-Goethe-Universität, Frankfurt am Main, Germany, has included the analysis of pottery excavated from several sites during the 1990s. This important investigation made us search through our old files for a statistical analysis of pottery from the same region, which although completed in 1981 was never published. The material came from approximately one hundred surface collections and seven excavated sites, spread over a wide area, and resulted from fieldwork in the 1960s and 1970s. Although old, the analysis remains relevant because it provides a broad geographical context for the more recent work, as well as a large body of independent data with which the new findings can be compared. It also indicates variations in both time and space that have implications for the human history of the area, hinting at the ongoing potential of broadscale pottery analysis in this part of West Africa and having wider implications of relevance to the study of archaeological pottery elsewhere.


1990 ◽  
Vol 7 (1) ◽  
pp. 1-7
Author(s):  
Anwar Ibrahim

Our understanding of science itself as a body of knowledge and as asystem of analysis and research has changed over the last decades, just asover the last two centuries, or especially after the age of Enlightement inEurope, science has become more powerful, more sophisticated and complex.It is rather difficult to determine where science ends and where technologybegins. In fact there is a gmwing awareness that the physical or nam sciences,as a means of studying and understanding nature, are relying on the more“humanistic“ and cultural approaches adopted by the social sciences or thehumanities. The tradition of natural science is being challenged by newdiscoveries of the non-physical and non-natural sciences which go beyondthe physical world.Certainly research is vital for the growth and development of all sciencesthat attempt to discover and understand the “secrets” of nature. The validityof any scientific theory depends on its research and methodological premisesand even that-its proposition or theories (in the words of a leading cosmologistand theoretical physicist, Stephen Hawking) -is tentative. Hawlung says: “Anyphysical theory is always provisional, in the sense that it is only a hypothesis:you can never prove it. No matter how many times the results of experimentsagree with some theory, you can never be sure that the next time the resultwill not contradict the theory. On the other hand, you can disprove a theoryby finding even a single observation that disagrees with the predictions ofthe theory.”The history of Western science is rooted in the idea of finding the ’truth’by objectivity. Nothing can be believed until there is a scientific proof ofits existence, or until it can be logically accepted by the rational mind. Theclassical scenario of scientific work gives you an austere picture of heroicactivity, undertaken against all odds, a ceaseless effort to subjugate hostileand menacing nature, and to tame its formidable forces. Science is depicted ...


This book is the product of a two-year research programme entitled Restarting European Long-Term Investment Finance (RELTIF), organized by Assonime and the Centre for Economic Policy Research (CEPR) in London. The programme brought together leading researchers from across the world to consider the causes of the persistently low level of investment in Europe, to examine the extent to which the financial system was a contributory factor and to identify possible policy remedies for it. It considered the relation of finance to corporate sector investment, the lending behaviour of banks, the provision of equity financing, the role of public sector institutions, regulation, and taxation. The chapters in this volume provide one of the most comprehensive and thorough analyses of any financial system that has been undertaken to date. They reflect a large body of research using new and existing data sets, employing advanced empirical tools, and exploiting the unique insights provided by the tumultuous events of the financial and sovereign debt crises. Together they comprise an exceptional body of knowledge to advance academic thinking and guide policy formulation in the future.


Genetics ◽  
2000 ◽  
Vol 156 (3) ◽  
pp. 1249-1257
Author(s):  
Ilya Ruvinsky ◽  
Lee M Silver ◽  
Jeremy J Gibson-Brown

Abstract The duplication of preexisting genes has played a major role in evolution. To understand the evolution of genetic complexity it is important to reconstruct the phylogenetic history of the genome. A widely held view suggests that the vertebrate genome evolved via two successive rounds of whole-genome duplication. To test this model we have isolated seven new T-box genes from the primitive chordate amphioxus. We find that each amphioxus gene generally corresponds to two or three vertebrate counterparts. A phylogenetic analysis of these genes supports the idea that a single whole-genome duplication took place early in vertebrate evolution, but cannot exclude the possibility that a second duplication later took place. The origin of additional paralogs evident in this and other gene families could be the result of subsequent, smaller-scale chromosomal duplications. Our findings highlight the importance of amphioxus as a key organism for understanding evolution of the vertebrate genome.


Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 789
Author(s):  
Klára Kosová ◽  
Miroslav Klíma ◽  
Ilja Tom Prášil ◽  
Pavel Vítámvás

Low temperatures in the autumn induce enhanced expression/relative accumulation of several cold-inducible transcripts/proteins with protective functions from Late-embryogenesis-abundant (LEA) superfamily including dehydrins. Several studies dealing with plants grown under controlled conditions revealed a correlation (significant quantitative relationship) between dehydrin transcript/protein relative accumulation and plant frost tolerance. However, to apply these results in breeding, field experiments are necessary. The aim of the review is to provide a summary of the studies dealing with the relationships between plant acquired frost tolerance and COR/LEA transcripts/proteins relative accumulation in cereals grown in controlled and field conditions. The impacts of cold acclimation and vernalisation processes on the ability of winter-type Triticeae to accumulate COR/LEA proteins are discussed. The factors determining dehydrin relative accumulation under controlled cold acclimation treatments versus field trials during winter seasons are discussed. In conclusion, it can be stated that dehydrins could be used as suitable indicators of winter survival in field-grown winter cereals but only in plant prior to the fulfilment of vernalisation requirement.


2006 ◽  
Vol 54 (1) ◽  
pp. 65 ◽  
Author(s):  
L. J. McManus ◽  
J. Sasse ◽  
C. K. Blomstedt ◽  
G. Bossinger

Mutation induction has played an integral role in the improvement of most commercially important crop species but has not been successfully applied to tree species because of their long reproductive cycles which hinder the use of the traditional seed-treatment approaches. Treatment of pollen with a chemical mutagen prior to pollination will, theoretically, allow stable, heterozygous mutant trees to be produced in a relatively short time and might facilitate mutagenesis of tree species. As the first step in testing this hypothesis, a controlled-pollination trial with chemically treated pollen was conducted in Eucalyptus globulus ssp. globulus (Labill.). Assessment of fruit, seed and seedlings from more than 500 pollinations associated mutagenic treatment of pollen with a significant reduction in seed set. Non-significant increases in capsule (fruit) abortion, the inhibition of seed germination and the incidence of aberration in seedlings were also noted. We argue that pollen treatment may be a useful means of producing Eucalyptus mutants with variation in flowering time, salinity and frost tolerance, lignification and other traits of scientific and economic importance.


2018 ◽  
Author(s):  
Mónica Lopes-Marques ◽  
André M. Machado ◽  
Raquel Ruivo ◽  
Elza Fonseca ◽  
Estela Carvalho ◽  
...  

AbstractFatty acids (FAs) constitute a considerable fraction of all lipid molecules with a fundamental role in numerous physiological processes. In animals, the majority of complex lipid molecules are derived from the transformation of FAs through several biochemical pathways. Yet, for FAs to enroll in these pathways they require an activation step. FA activation is catalyzed by the rate limiting action of Acyl-CoA synthases. Several Acyl-CoA enzyme families have been previously described and classified according to the chain length of FA they process. Here, we address the evolutionary history of the ACSBG gene family which activates, FA with more than 16 carbons. Currently, two different ACSBG gene families, ACSBG1 and ACSBG2, are recognized in vertebrates. We provide evidence that a wider and unequal ACSBG gene repertoire is present in vertebrate lineages. We identify a novel ACSBG-like gene lineage which occurs specifically in amphibians, ray finned fish, coelacanths and chondrichthyes named ACSBG3. Also, we show that the ACSBG2 gene lineage duplicated in the Theria ancestor. Our findings, thus offer a far richer understanding on FA activation in vertebrates and provide key insights into the relevance of comparative and functional analysis to perceive physiological differences, namely those related with lipid metabolic pathways.


2019 ◽  
Author(s):  
Laura Hernández ◽  
Alberto Vicens ◽  
Luis Enrique Eguiarte ◽  
Valeria Souza ◽  
Valerie De Anda ◽  
...  

ABSTRACTDimethylsulfoniopropionate (DMSP), an osmolyte produced by oceanic phytoplankton, is predominantly degraded by bacteria belonging to the Roseobacter lineage and other marine Alphaproteobacteria via DMSP-dependent demethylase A protein (DmdA). To date, the evolutionary history of DmdA gene family is unclear. Some studies indicate a common ancestry between DmdA and GcvT gene families and a co-evolution between Roseobacter and the DMSP-producing-phytoplankton around 250 million years ago (Mya). In this work, we analyzed the evolution of DmdA under three possible evolutionary scenarios: 1) a recent common ancestor of DmdA and GcvT, 2) a coevolution between Roseobacter and the DMSP-producing-phytoplankton, and 3) pre-adapted enzymes to DMSP prior to Roseobacter origin. Our analyses indicate that DmdA is a new gene family originated from GcvT genes by duplication and functional divergence driven by positive selection before a coevolution between Roseobacter and phytoplankton. Our data suggest that Roseobacter acquired dmdA by horizontal gene transfer prior to exposition to an environment with higher DMSP. Here, we propose that the ancestor that carried the DMSP demethylation pathway genes evolved in the Archean, and was exposed to a higher concentration of DMSP in a sulfur rich atmosphere and anoxic ocean, compared to recent Roseobacter ecoparalogs (copies performing the same function under different conditions), which should be adapted to lower concentrations of DMSP.


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