Epigenetics Comes of Age

Epigenetics beyond epigenetic structures (DNA methylation and histonemodification/chromosome remodeling). Part I

admin — Sun, 26 Sep 2010 14:25:04 +0000

Epigenetics beyond epigenetic structures (DNA methylation and histonemodification/chromosome remodeling). Part I Since its discovery by Theodore Boveri, by the end of 19 century centrosomes, and centrioles within them, have been recognized as major players in cell division. However, only recently have biologists made real progress in understanding their structure and function. (more…)

Sensory-driven Sympatric Speciation, again

admin — Sat, 14 Aug 2010 14:29:46 +0000

Sensory-driven sympatric speciation is observed and demonstrated in a wide range of animals, from invertebrates (insects) to vertebrates (fishes and amphibiansis). It is based on changes in mate preferences of individuals for particular individuals within a single population that display behavioral traits or specific visual, olfactory and auditory stimuli. (more…)

Sensory-driven Sympatric Speciation (Speciation does not need changes in genetic information)

admin — Wed, 11 Aug 2010 13:27:06 +0000

The genetic model of speciation requires physical (geographical) isolation of populations as a sine qua non for the formation of new species. Only under geographical isolation spontaneous changes in DNA (genes, regulatory sequences, etc) can accumulate and finally lead to the reproductive (postzygotic) isolation of the populations when they come in contact again. (more…)

The brain is the user of the genetic toolkit

admin — Fri, 02 Jul 2010 23:00:25 +0000

On may 14, 2010, a group of researchers from Friedrich Miescher Institute in Basel, Switzerland and Universität Heidelberg, Germany reported that in response to light, as well as in response to synaptic stimulation in hippocampal and cortical neurons, retinal neurons upregulate synthesis of the miR-183/96/182 cluster, miR-204, and miR211. This is another experimental example of the neural control of gene expression. These results add to the abundant volume of empirical evidence on the role of the nervous system in regulating gene expression. and in response to synaptic stimulation in hippocampal and cortical neurons. (more…)

The Evolution of the Nervous System and Cambrian Explosion - A Causal Relationship

admin — Tue, 29 Jun 2010 02:10:24 +0000

There is an unmistakable correlation between the evolution of the nervous system (differentiation of the nerve cell implied) and the evolution of eumetazoan life during the Cambrian explosion. But does it mean that the correlation is a manifestation of a causal relationship between them? (more…)

On the Nature of Evolutionary Change

admin — Sun, 27 Jun 2010 03:17:54 +0000

Evolutionary Changes Involve no Changes in Genes

The crux of the process of evolution is how the novel evolutionary change occurs. The conventional explanation given is by specific changes in genes, gene mutations. Although this is taken for granted and self-evident no one has ever shown either in theory (in concrete causal terms) or illustrated with concrete examples how a change in a particular gene brought about an evolutionary change. (more…)

Butterflies, Frogs, humans and the Genetic Paradigm of Evolution

admin — Thu, 17 Jun 2010 15:20:24 +0000

Ask a biology student on what determined evolutionary transitions from a body plan to another or even from a species to a closely related species and he unhesitantly will tell you that it is a natural result of changes in existing genes and the evolution of new genes under the action of natural selection. A more advanced student, from a neo-genetic standpoint, will tell you that changes in regulatory sequences of genes may be all that is needed for the evolution of living forms. (more…)

Biological Systems vs. von Neumann’s Machine

admin — Mon, 31 May 2010 17:45:34 +0000

In an extremely intriguing book, “Decoding Reality” (Oxford University Press, 2010) V. Vedral, among other things, compares living systems with the von Neumann’s machine consisting, in his description, of four basic components:- the protein synthesizing machine, M,- the biological nano-engine (akin to Xerox copier), X- enzymes which act as controllers switching the nano-engine on and off, C- the DNA information set. (more…)

Craig’s Group’s New Breakthrough

admin — Sun, 23 May 2010 02:47:02 +0000

Craig’s Group’s New Breakthrough

On May 20 the J.Craig Venter Institute issued the following press release: (more…)

Dangers of Preamture Extrapolation in Biology (Part 2)

admin — Thu, 20 May 2010 02:19:40 +0000

Dangers of Preamture Extrapolation in Biology (Part 2)

The Dogma of Genetic Sex Determination For more than a century conventional textbook knowledge has been that sex is genetically determined by sex chromosomes. (more…)