Friday, July 31, 2015

GMO Double Talk

Reading science articles submitted to Science journals is very boring...after a while you can actually understand the jargon, and see how they use word changes to cover themselves...also to kiss the butts of those who fund them...
Like this...Playing up the false need for GMOs in the beginning of the article.
"The effects of uncontrolled population growth have produced a series of looming crises that not only have biology at their base but also present an arena in which practitioners of the biological sciences will be critical contributors. The analyses that emerged from the NAS study (National Research Council Committee, 2009) identified four areas in which biology is poised to make pivotal contributions: (1) the provision of food for the growing population; (2) the development of alternative energy sources; (3) the promotion of health; and (4) environmental protection."

But...then by the end issues a subtle warning against doing so...
..."The study of biochemical adaptations in animals and plants, which does integrate across the hierarchy, requires focusing on a few relevant levels (Fig. 3B)."

..."(B) In animals and plants, the level of the organism has a series of defining lower levels that reflect their multicellularity. While most fields of biology focus on one level or contiguous levels, an animal or plant's ecology can be studied by characterizing its biochemical adaptations to the environment in which it evolved (green arrows), an area of emphasis developed by Hochachka and Somero."

..."In addition to being evolutionarily basal and having a simplified hierarchy of life, microbes also have certain traits that, when considered, provide insight into the fundamental capacities and limitations of life processes. Relevant to the discussion here is the widespread occurrence of horizontal gene transfer (HGT) in the Bacteria (Darmon and Leach, 2014) and Archaea (Wolf et al., 2012), and their metabolic diversity (Kluyver and van Niel, 1956) (Fig. 4). While concepts of evolutionary selection, as developed by Darwin, apply to both microbiological and macrobiological organisms, the Mendelian vertical inheritance of traits and associated genetic patterns is largely restricted to groups within the Eucarya and, as such, is a derived feature. Further, the propensity for HGT seems to have attenuated in the radiation of the Eucarya, particularly among the animals, although evidence is increasing that it is more prevalent than previously thought (Boto, 2014). Because we now know that the most common mode of acquisition of traits occurs by HGT in Bacteria and Archaea, we can no longer use the ‘Modern Synthesis’ to describe the genetic basis of evolution. With this change in perspective, Koonin has suggested that we need a ‘Post-Modern Synthesis’ that encompasses the genetic mechanisms of all branches of the Tree of Life (Koonin, 2012; Koonin and Wolf, 2012). Along with the relative instability of their genome, a defining theme in microbes is their metabolic diversity. "

..."The array of microbial metabolisms includes all the known ways in which organisms can obtain carbon (autotrophy or heterotrophy), reducing equivalents (lithotrophy or organotrophy), and energy (phototrophy or chemotrophy), and they combine these in nearly every way possible. These metabolic strategies use a wide variety of terminal electron donors and acceptors. By definition, the acquisition of the mitochondrion is the hallmark characteristic of the Eucarya; this innovation nevertheless has almost exclusively limited the Eucarya to oxygen as a terminal electron acceptor for respiration."

..."Another byproduct of advances in sequencing technology has been the recognition that intimate animal and plant interactions with microbes are now, as they have been throughout geological history, a common theme among life forms. With the seminal work of Lynn Margulis, biologists became aware that the eukaryotic cell arose through a symbiotic event (Sagan, 1967). Interestingly, this event, i.e. the acquisition of the mitochondrion, appears to have occurred once and spurred the radiation of all of the Eucarya (Lane, 2014). The presence of mitochondria augmented the efficiency of cellular bioenergetics by increasing the membrane surface area for the production of ATP through cellular respiration. In addition, over evolutionary history, much of the mitochondrial genome has been transferred to the nucleus, such that the mitochondria energetically support the much larger nuclear genome. These relationships between the nucleus and mitochondria of the cell provide eukaryotes with orders of magnitude more energy per gene than is available per gene for the Bacteria and Archaea (Lane, 2014). In addition to its well-recognized role as the ‘powerhouse’ of the cell, recent studies have indicated that the mitochondria control many more cellular functions (Mitra and Lippincott-Schwartz, 2010; Antico Arciuch et al., 2012; Friedman and Nunnari, 2014). For example, the mitochondrial network in the cell appears to be electrically coupled (De Giorgi et al., 2000) and coordinates such critical processes as cell death, cell proliferation, autophagy (Rambold and Lippincott-Schwartz, 2011), cell differentiation (Mitra et al., 2012) and aging (Lee and Wei, 2012). The view seems to be emerging that perhaps the mitochondrial network is actually the ‘brains’ of the cell, controlling much of the cell's processes, including activities of the nucleus.

Whereas biologists have known for decades about the endosymbiotic origin of the eukaryotic cell, intimate interactions of microbes with animals and plants had been thought to be rare and restricted to only a few groups. The recent, technology-enabled ability to identify and characterize uncultured microbial cells occurring in large communities has demonstrated that most animals and plants rely on interactions with microbes (Hadfield, 2011; Gilbert et al., 2012; McFall-Ngai et al., 2013). This dependence is not surprising, given that the differences in characters between microbiological and macrobiological forms (Fig. 4) render them complementary, i.e. by forming alliances they increase one another's scope. To date, over half of the nearly 40 animal phyla have members in which symbiotic associations have been described, with the most speciose third all having representatives with such alliances "

.."Among all of the animal–microbe interactions studied over the past 20 years, the human microbiota continues to receive the most attention. Researchers have identified stable, predictable communities associated with several sites on the body, including the skin and the digestive, respiratory, excretory and reproductive tracts. These communities have been studied in health and disease over the trajectory of ontogeny. Because the data have determined that the microbiota is a central player in the biology of humans,"

..."The expansion of the field into this frontier would usher in the study of how the integrated activities of the resident two or three domains of life, i.e. the holobiont (Gilbert, 2014), are coordinated in the metaorganism in responses to various environmental pressures. Thus, as we go forward in the study of the mechanisms underlying the biochemical adaptations of animals, let's not forget their microbes!"

Giving microbes their due – animal life in a microbially dominant world
Margaret J. McFall-Ngai*
http://jeb.biologists.org/content/218/12/1968.full


Traits of the microbiological and macrobiological worlds that promote their partnering intimate association. Picture.

No comments:

Post a Comment