metabolism

A molecular visualizer of worthwhile molecular biology

Ruben Gonzalez Jr.: Molecular Visualizer Associate Professor and Director of Graduate Studies, Department of Chemistry, Columbia University. Age 42 By Jef Akst | September 1, 2014 Excerpt: “Much of his group’s current work involves extending discoveries about translation in E. coli to the process in eukaryotes, with an eye toward human health and disease.” My comment: That sums up the frustration that other serious scientists must share when they hear pseudoscientific nonsense touted about mutations, natural selection, and the evolution…

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Behavior (3): All responses are RNA-mediated in bees

See: Honey bees as a model for understanding mechanisms of life history transitions. Excerpt: “In this review we discuss the physiological and genetic mechanisms of this behavioral transition, which include large scale changes in hormonal activity, metabolism, flight ability, circadian rhythms, sensory perception and processing, neural architecture, learning ability, memory and gene expression.” My comment: An earlier review by Eleckonich and Robinson (2000) “Organizational and activational effects of hormones on insect behavior” cited our 1996 review of epigenetically-effected organization and activation…

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Exploding genomes and chromosomal rearrangements via RNA-mediated events

Gibbon genome and the fast karyotype evolution of small apes This is an open access article reported as: Gibbon genome sequence deepens understanding of primates rapid chromosomal rearrangements Excerpt: The number of chromosomal rearrangements in the gibbons is remarkable, Rogers said. “It is like the genome just exploded and then was put back together,” he said. “Up until recently, it has been impossible to determine how one human chromosome could be aligned to any gibbon chromosome because there are so…

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Pattern recognition and conserved receptors (TAARs)

Olfactory Receptor Patterning in a Higher Primate Excerpt: We found that TAARs are also expressed in the macaque OE, suggesting that these receptors may also function as chemosensory receptors in the human nose. My comment: The article links the senior author’s prior works from nutrient-dependent RNA-mediated events and the de novo Creation of odorant receptor (OR) genes to her 2005 co-authored work on the hormone-organized control of these RNA-mediated events: Feedback loops link odor and pheromone signaling with reproduction. Excerpt:”At…

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Nutrient-dependent erythropoiesis and anemia

A critical role for mTORC1 in erythropoiesis and anemia Excerpt 1): “Cells must coordinate their rate of growth and proliferation with the availability of nutrients. mTOR , a serine-threonine kinase, is one the key proteins responsible for nutrient signaling in eukaryotic cells. mTOR is activated by conditions that signal energy abundance, such as the availability of amino acids, growth factors, and intracellular ATP. Activated mTOR then phosphorylates a set of downstream targets that promote anabolic processes, such as protein translation…

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A relatively young branch of science called epigenetics

Epigenetics: genes, environment and the generation game New research claims that environmental factors affect not just an individual’s genes but those of their offspring too. Diabetes, obesity – even certain phobias – may all be influenced by the behaviour of our forebears by Angela Saini, The Observer, Saturday 6 September 2014 Excerpt 1): “…she was kept on a near-starvation diet when she was close to giving birth.” Excerpt 2: with my emphasis): This puzzling study, published last month, echoes many…

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Biophysically constrained beginnings of RNA and DNA

Any anonymous participant in the discussion of: DNA may have had humble beginnings as nutrient carrier (Sep 01, 2014 by Adam Hadhazy) asks: “when are you going to keep quiet?” In a series of responses, I have explained the problem I have with honoring his request. The following excerpts from Wikipedia and other sources are loosely strung together because there is no point to providing more extensive details of biologically-based cause and effect until others accept the fact that mutations…

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Baby talk: More misrepresentations of ecological adaptations

Evolution’s Baby Steps by Carl Zimmer Excerpt 1) “When organisms find themselves in a new environment, they develop in a way that helps them cope with their new surroundings. Their descendants may acquire mutations that encode that anatomy in their genes. Eventually evolution takes them beyond where plasticity alone could take them.” My comment: It’s time for science journalists to stop touting this nonsense (above). Ecological variation leads from nutrient uptake in new environments to RNA-mediated amino acid substitutions. If…

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Comparing divergent model organisms

Comparative analysis of the transcriptome across distant species Excerpt: Overall, our results underscore the importance of comparing divergent model organisms to human to highlight conserved biological principles (and disentangle them from lineage-specific adaptations). My comment: In the detailed comparisons of divergent model organisms portrayed in Nutrient-dependent/pheromone-controlled adaptive evolution: a model, I underscored what is known about cell type differentiation in species from microbes to man. By placing what is known into the context of nutrient-dependent amino acid substitutions and biodiversity…

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microRNAs differentiate neuronal cell types

microRNAs: key triggers of neuronal cell fate Excerpt: “In light of the fact that miRNAs have very precise expression patterns depending on the cell type, tissue and/or developmental stage; it is challenging to generalize a single mechanism to regulate their expression and to identify the target genes that each miRNA has during each stage of neurogenesis. Thus, the combination of bioinformatic tools and experimental techniques will help in the study of miRNAs role in early neurogenesis and how they, their…

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