Evolution of Plant NLRs: From Natural History to Precise Modifications

2020 ◽  
Vol 71 (1) ◽  
pp. 355-378 ◽  
Author(s):  
Janina Tamborski ◽  
Ksenia V. Krasileva

Nucleotide-binding leucine-rich repeat receptors (NLRs) monitor the plant intracellular environment for signs of pathogen infection. Several mechanisms of NLR-mediated immunity arose independently across multiple species. These include the functional specialization of NLRs into sensors and helpers, the independent emergence of direct and indirect recognition within NLR subfamilies, the regulation of NLRs by small RNAs, and the formation of NLR networks. Understanding the evolutionary history of NLRs can shed light on both the origin of pathogen recognition and the common constraints on the plant immune system. Attempts to engineer disease resistance have been sparse and rarely informed by evolutionary knowledge. In this review, we discuss the evolution of NLRs, give an overview of previous engineering attempts, and propose how to use evolutionary knowledge to advance future research in the generation of novel disease-recognition capabilities.

Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mourad Ahmim ◽  
Hafid Aroudj ◽  
Farouk Aroudj ◽  
Saaid Saidi ◽  
Samir Aroudj

Abstract The common genet (Genetta genetta Linnaeus, 1758) is a rare and protected mammal species in Algeria. We report the first melanistic individual of this species ever recorded in North Africa. Such animals have only been recorded in Spain and Portugal so far. It is unclear why melanistic common genets seem to be so rare in its African range. More research is needed to determine the true occurrence of melanistic individuals, and what the evolutionary history of melanism is in common genets.


Author(s):  
Sergio A Muñoz-Gómez ◽  
Keira Durnin ◽  
Laura Eme ◽  
Christopher Paight ◽  
Christopher E Lane ◽  
...  

Abstract A most interesting exception within the parasitic Apicomplexa is Nephromyces, an extracellular, probably mutualistic, endosymbiont found living inside molgulid ascidian tunicates (i.e., sea squirts). Even though Nephromyces is now known to be an apicomplexan, many other questions about its nature remain unanswered. To gain further insights into the biology and evolutionary history of this unusual apicomplexan, we aimed to (1) find the precise phylogenetic position of Nephromyces within the Apicomplexa, (2) search for the apicoplast genome of Nephromyces, and (3) infer the major metabolic pathways in the apicoplast of Nephromyces. To do this, we sequenced a metagenome and a metatranscriptome from the molgulid renal sac, the specialized habitat where Nephromyces thrives. Our phylogenetic analyses of conserved nucleus-encoded genes robustly suggest that Nephromyces is a novel lineage sister to the Hematozoa, which comprises both the Haemosporidia (e.g., Plasmodium) and the Piroplasmida (e.g., Babesia and Theileria). Furthermore, a survey of the renal sac metagenome revealed 13 small contigs that closely resemble the genomes of the non-photosynthetic reduced plastids, or apicoplasts, of other apicomplexans. We show that these apicoplast genomes correspond to a diverse set of most closely related but genetically divergent Nephromyces lineages that co-inhabit a single tunicate host. In addition, the apicoplast of Nephromyces appears to have retained all biosynthetic pathways inferred to have been ancestral to parasitic apicomplexans. Our results shed light on the evolutionary history of the only probably mutualistic apicomplexan known, Nephromyces, and provide context for a better understanding of its life style and intricate symbiosis.


2011 ◽  
Vol 193 (4) ◽  
pp. 1049-1063 ◽  
Author(s):  
Jia-Xing Yue ◽  
Blake C. Meyers ◽  
Jian-Qun Chen ◽  
Dacheng Tian ◽  
Sihai Yang

2021 ◽  
Vol 12 (1) ◽  
pp. 101-112
Author(s):  
Kishore Sugali ◽  
Chris Sprunger ◽  
Venkata N Inukollu

The history of Artificial Intelligence and Machine Learning dates back to 1950’s. In recent years, there has been an increase in popularity for applications that implement AI and ML technology. As with traditional development, software testing is a critical component of an efficient AI/ML application. However, the approach to development methodology used in AI/ML varies significantly from traditional development. Owing to these variations, numerous software testing challenges occur. This paper aims to recognize and to explain some of the biggest challenges that software testers face in dealing with AI/ML applications. For future research, this study has key implications. Each of the challenges outlined in this paper is ideal for further investigation and has great potential to shed light on the way to more productive software testing strategies and methodologies that can be applied to AI/ML applications.


Heredity ◽  
2002 ◽  
Vol 88 (4) ◽  
pp. 235-242 ◽  
Author(s):  
M Ratkiewicz ◽  
S Fedyk ◽  
A Banaszek ◽  
L Gielly ◽  
W Chȩtnicki ◽  
...  

2019 ◽  
pp. 196-206
Author(s):  
Kimberley J. Hockings ◽  
Robin I.M. Dunbar

Humans and alcohol have shared a very long history. In this final chapter, we highlight some of the key findings that emerge from the chapters in this book, in particular the evolutionary history of our adaptation to alcohol consumption and the social role that alcohol consumption plays, and has played, in human societies across the world. This raises a major contradiction in the literature, namely the fact that, despite this long history, the medical profession typically views alcohol as destructive. We draw attention to several avenues that would repay future research and how humans’ relationship with alcohol stands to change and evolve.


2019 ◽  
Vol 28 (6) ◽  
pp. 587-592 ◽  
Author(s):  
Cory J. Clark ◽  
Brittany S. Liu ◽  
Bo M. Winegard ◽  
Peter H. Ditto

Humans evolved in the context of intense intergroup competition, and groups comprised of loyal members more often succeeded than groups comprised of nonloyal members. Therefore, selective pressures have sculpted human minds to be tribal, and group loyalty and concomitant cognitive biases likely exist in all groups. Modern politics is one of the most salient forms of modern coalitional conflict and elicits substantial cognitive biases. The common evolutionary history of liberals and conservatives gives little reason to expect protribe biases to be higher on one side of the political spectrum than the other. This evolutionarily plausible null hypothesis has been supported by recent research. In a recent meta-analysis, liberals and conservatives showed similar levels of partisan bias, and several protribe cognitive tendencies often ascribed to conservatives (e.g., intolerance toward dissimilar other people) were found in similar degrees in liberals. We conclude that tribal bias is a natural and nearly ineradicable feature of human cognition and that no group—not even one’s own—is immune.


2012 ◽  
Vol 279 (1736) ◽  
pp. 2246-2254 ◽  
Author(s):  
Fabien Burki ◽  
Noriko Okamoto ◽  
Jean-François Pombert ◽  
Patrick J. Keeling

An important missing piece in the puzzle of how plastids spread across the eukaryotic tree of life is a robust evolutionary framework for the host lineages. Four assemblages are known to harbour plastids derived from red algae and, according to the controversial chromalveolate hypothesis, these all share a common ancestry. Phylogenomic analyses have consistently shown that stramenopiles and alveolates are closely related, but haptophytes and cryptophytes remain contentious; they have been proposed to branch together with several heterotrophic groups in the newly erected Hacrobia. Here, we tested this question by producing a large expressed sequence tag dataset for the katablepharid Roombia truncata , one of the last hacrobian lineages for which genome-level data are unavailable, and combined this dataset with the recently completed genome of the cryptophyte Guillardia theta to build an alignment composed of 258 genes. Our analyses strongly support haptophytes as sister to the SAR group, possibly together with telonemids and centrohelids. We also confirmed the common origin of katablepharids and cryptophytes, but these lineages were not related to other hacrobians; instead, they branch with plants. Our study resolves the evolutionary position of haptophytes, an ecologically critical component of the oceans, and proposes a new hypothesis for the origin of cryptophytes.


2017 ◽  
Author(s):  
Philipp Rössner

More than England and other states the German principalities were, in the preindustrial period, hampered by silver outflow and persistent pressures on the balance of payments which led to idiosyncratic models and strategies of economic development usually but not entirely helpfully called “Cameralism”. It is less well understood how Cameralism as a policy of order and development and monetary theory went together. The present paper will attempt a sketch of these working mechanisms as well as provide a few angles for new perspectives and future research. A first section after the brief introduction studies general issues of development in relation to balance of payment constraints (II), followed by the discourses on whether the domestic currency ought to remain stable in terms of intrinsic (silver) value (III), or whether it may be debased so as to raise domestic exports and competitiveness (IV). Both options were considered, at times and by varying actors, as valid strategies of promoting economic development, especially export-led growth, although most contemporaries viewed coin debasement as harmful to the economy. A fifth section discusses an alternative to the aforementioned strategies, by raising effective monetary mass through increasing velocity. Since the middle ages and into the nineteenth century the German economic tradition had a clear understanding of how velocity could be managed and the common weal stimulated by an increase in “vivacity” of circulation (V). Upon hindsight it appears that we find here a powerful programme towards promoting economic development and Europe’s rise towards capitalism. A conclusion will offer some thoughts for further research (VI).


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