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Mexico City, Mexico

The Center for Research and Advanced Studies of the National Polytechnic Institute is a Mexican non-governmental scientific research affiliated to the National Polytechnic Institute and founded by president Adolfo López Mateos on 17 April 1961, initially planned as a posgraduate department of the National Polytechnic Institute, which was later modified by President José López Portillo, on the 17 September 1982.The modification by President Portillo stipulates that it is a decentralized organ of public interest, with legal personality and own patrimony. Cinvestav receives an annual subsidy by the Federal Government to fund its operations. Wikipedia.

Heil M.,CINVESTAV | Karban R.,University of California at Davis
Trends in Ecology and Evolution | Year: 2010

In spite of initial doubts about the reality of 'talking trees', plant resistance expression mediated by volatile compounds that come from neighboring plants is now well described. Airborne signals usually improve the resistance of the receiver, but without obvious benefits for the emitter, thus making the evolutionary explanation of this phenomenon problematic. Here, we discuss four possible non-exclusive explanations involving the role of volatiles: in direct defense, as within-plant signals, as traits that synergistically interact with other defenses, and as cues among kin. Unfortunately, there is a lack of knowledge on the fitness consequences of plant communication for both emitter and receiver. This information is crucial to understanding the ecology and evolution of plant communication via airborne cues. © 2009 Elsevier Ltd. All rights reserved.

Plants secrete extrafloral nectar (EFN) as an induced defense against herbivores. EFN contains not only carbohydrates and amino acids but also pathogenesis-related proteins and other protective enzymes, making EFN an exclusive reward. EFN secretion is commonly induced after wounding, likely owing to a jasmonic acid-induced cell wall invertase, and is limited by phloem sucrose availability: Both factors control EFN secretion according to the optimal defense hypothesis. Non-ant EFN consumers include parasitoids, wasps, spiders, mites, bugs, and predatory beetles. Little is known about the relevance of EFN to the nutrition of its consumers and, hence, to the structuring of arthropod communities. The mutualism can be established quickly among noncoevolved (e.g., invasive) species, indicating its easy assembly is due to ecological fitting. Therefore, increasing efforts are directed toward using EFN in biocontrol. However, documentation of the importance of EFN for the communities of plants and arthropods in natural, invasive, and agricultural ecosystems is still limited. © 2015 by Annual Reviews. All rights reserved.

Journal of Physiology | Year: 2014

Plants respond to mechanical wounding, herbivore feeding or infection by pathogens with the release of volatiles. Small C6 molecules termed green-leaf volatiles form a general element in most of these blends; however, the overall composition is usually sufficiently specific that other organisms are able to determine the nature of the attacker. Receivers of herbivore-induced volatile organic compounds (HI-VOCs) comprise distant parts of the same plant ('within-plant signalling'), neighbouring plants ('plant-plant signalling'), herbivores, and multiple carnivores that respond to the 'plant's cry for help', such as parasitoids and hyperparasitoids, entomopathogenic nematodes, and predatory mites, beetles, bugs and birds. In spite of intensive research efforts, many central questions still remain. How do plants perceive volatiles? What is the relative impact of each of the interactions with different receivers of HI-VOCs on the fitness of the emitting plant and that of the interacting organisms? How long can these compounds remain stable in the atmosphere? Why are VOC-mediated effects on herbivores and beneficial organisms not used as a common tool in sustainable agriculture? Here, I briefly summarize the ecological effects of HI-VOC perception and discuss the most pertinent questions raised by participants at the 32nd New Phytologist Symposium in Buenos Aires. © 2014 New Phytologist Trust.

Frontiers in Pharmacology | Year: 2015

Diverse neuropsychiatric disorders present dysfunctional memory and no effective treatment exits for them; likely as result of the absence of neural markers associated to memory. Neurotransmitter systems and signaling pathways have been implicated in memory and dysfunctional memory; however, their role is poorly understood. Hence, neural markers and cerebral functions and dysfunctions are revised. To our knowledge no previous systematic works have been published addressing these issues. The interactions among behavioral tasks, control groups and molecular changes and/or pharmacological effects are mentioned. Neurotransmitter receptors and signaling pathways, during normal and abnormally functioning memory with an emphasis on the behavioral aspects of memory are revised. With focus on serotonin, since as it is a well characterized neurotransmitter, with multiple pharmacological tools, and well characterized downstream signaling in mammals' species. 5-HT1A, 5-HT4, 5-HT5, 5-HT6 and 5-HT7 receptors as well as SERT (serotonin transporter) seem to be useful neural markers and/or therapeutic targets. Certainly, if the mentioned evidence is replicated, then the translatability from preclinical and clinical studies to neural changes might be confirmed. Hypothesis and theories might provide appropriate limits and perspectives of evidence. © 2015 Meneses.

Multiple plant species are engaged in defensive mutualisms with members of the third trophic level. However, mutualisms are prone to exploitation by low-quality symbionts that do not provide the adequate service to their host. Can mutualisms proceed only when hosts identify their symbionts in advance or continuously monitor their activity, or are there other mechanisms to avoid the invasion of mutualisms by exploiters? High-reward species amongst Mesoamerican Acacia myrmecophytes are dominantly colonized by defending mutualistic ants, whereas about 50% of the low-reward hosts are inhabited by non-defending exploiters. I followed the development of recently founded ant colonies on a high-reward and a low-reward Acacia host species over 7 months, to investigate whether reward production correlates with a preferred maintenance of defending ants on the respective hosts. Ant diversity decreased sooner on high-reward than on low-reward hosts, and mutualistic ants were more likely to finally dominate the high-reward hosts. I observed an increased frequency of mutualists replacing parasites at high initial rates of reward production. Apparently, higher nectar provisioning by the host plants shifted the competitive balance between mutualistic and parasitic ants. Independently of the causal reason for the different secretion rates, producing more nectar thereby favours the maintenance of defending mutualists on high-reward hosts. Synthesis. The aggressiveness that enables ants to outcompete other ants also underlies their defensive effect against herbivores. I conclude that hosts can preferably associate with high-quality mutualists without measuring their effectiveness. Mutualisms remain stable when partner screening is based on traits that are relevant for the mutualistic interaction, with no need for the host to have information on the quality or identity of the symbiont. © 2013 The Authors. Journal of Ecology © 2013 British Ecological Society.

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