…the exosome employs a general mechanism of recruitment to defined substrates and that this process is regulated through adaptor proteins.
Journal article excerpt: (subscription required)
The nuclear exosome processes precursors of numerous stable RNA species (Allmang et al., 1999) (rRNA, snoRNA, and snRNA) and degrades by-products of RNA processing reactions. Additionally, it targets for surveillance numerous cryptic unstable transcripts (CUTs) (Wyers et al., 2005) and aberrant RNAs. In the cytoplasm the exosome degrades aberrant mRNAs identified by the NMD (nonsense-mediated decay) (Takahashi et al., 2003) and NGD (no-go decay) (Doma and Parker, 2006) pathways.
My comment: Attempts to place the general molecular mechanisms of biophysically constrained nutrient-dependent substrates’ RNA-mediated amino acid substitutions and protein folding chemistry that determines cell types in all individuals of all genera into the context of neo-Darwinian theories have continued to become increasingly more foolish.
See for example: Steven Tucker: The man who found the Homo Naledi fossils
When will students in your country be taught what is known about cell type differentiation instead of being taught to believe in ridiculous theories? See, for example:
The key lies in how genes involved in facial development and human facial diversity are regulated—how much, when and where the genes are expressed— rather than dissimilarities among the genes themselves.
International Society for Extracellular Vesicles (ISHE) exclusive video collection
includes the panel discussion: Exosomes Role in the Future of Medicine
See also: Context-specific microRNA function in developmental complexity
When also considering the large number of primate-specific miRNAs expressed in the brain (Berezikov et al., 2006) and that a single pyramidal neuron in the cortex may form up to 10000 synapses with other cells, it is tantalizing to hypothesize a role for miRNA as key regulatory molecules in the development of the exquisitely complex programmes of gene expression and the decentralized modifications of individual synaptodendritic connections that are required for the cortical complexity observed in the human brain.
My comment: Do not be the last serious scientist in the world to learn how cell type differentiation occurs in all cells of all individuals of all living genera. Other serious scientists will think you have always been a biologically uninformed theorist.
See also: The Complexity of Human Ribosome Biogenesis Revealed by Systematic Nucleolar Screening of Pre-rRNA Processing Factors
…among the human proteins identified, 59 have a yeast homolog that has not been examined for a role in ribosome synthesis. Significantly, these include putative methyltransferases, protein modification enzymes, and structural cellular components, as well as gene products
involved in translation, pre-mRNA splicing, or DNA replication. These are all cellular processes recently shown to share highly specific trans-acting factors with ribosome synthesis.
My comment: It should be obvious that mutations, which perturb thermodynamic cycles of RNA-mediated protein biosynthesis and degradation cannot be linked to the evolution of biodiversity, which is nutrient-dependent and controlled by the physiology of reproduction in all living genera.
See also: Viral and Cellular Genomes Activate Distinct DNA Damage Responses
and Loss of lamin A function increases chromatin dynamics in the nuclear interior, which was reported as: Preventing chromosomal chaos: Protein-based genome-stabilizing mechanism discovered
According to Garini, this protein-mediated mechanism is fundamental to the stability of life as we know it.
The stability of life is nutrient-dependent, receptor-mediated and the stability of species is controlled by the physiology of reproduction in the context of chromosomal rearrangements, not mutations or natural selection or evolution.
See also: Exosomes and the RNA-mediated future of medicine (2)
For a ridiculous misrepresentation of biologically-based cause and effect, see: One crank dies, another rises to take his place PZ Myers attacks anyone who does not support his ridiculous opinions.
Behold James Vaughn Kohl. (my comment from Jan 3, 2014 may not appear unless you set the post rating to 1.0)
Ecological adaptation occurs via the epigenetic effects of nutrients on alternative splicings of pre-mRNA which result in amino acid substitutions that differentiate all cell types of all individuals of all species. The control of the differences in cell types occurs via the metabolism of the nutrients to chemical signals that control the physiology of reproduction.
These facts do not refute evolution; they simply refute the ridiculous theory of mutation-initiated natural selection that most people here were taught to believe is the theory of evolution.
See also: I repeat: Octopuses are NOT aliens
The problem for atheists becomes bigger almost every day.Where is PZ Myers, when we need to learn more about cell type differentiation via mutations, now that all serious scientists have abandoned that pseudoscientific nonsense because they have learned about biologically-based cause and effect?See for example: DNA methylation pathways and their crosstalk with histone methylation http://dx.doi.org/10.1038/nrm4043Why isn’t little PeeZee slamming down the creationists now that they reported the link from virus-driven entropic elasticity to genomic entropy?
The best way to refute pseudoscientific nonsense linked to evolutionary theories invented by neo-Darwinists is with facts about cell type differentiation in the context of climate change and the physiology of reproduction, which links ecological variation to ecological adaptations via the microRNA/messenger RNA balance. The balance is linked to biodiversity via chromosomal rearrangements, not by virus-driven mutations that cause gene loss.See: Mayo Clinic Researchers Find New Code That Makes Reprogramming of Cancer Cells Possible https://www.youtube.com/watch?v=yGYTLOGZ40U
See also: http://freethoughtblogs.com/pharyngula/2014/01/06/one-crank-dies-another-rises-to-take-his-place/“…he was actually a biologist, had a Ph.D. in zoology, and taught at the University of Vermont. He had a “scientific” theory, which was his, which he thought explained all that evolutionary change while refuting those silly scientists who believed that mutations occurred. No! Evolution was all due to chromosome rearrangements, which somehow are not mutations, and he also somehow ignored the existence of allelic differences between species…”Mutations perturb protein folding, which is why they cannot be linked to evolution.The differences in alleles are nutrient dependent and they link RNA-mediated events to the biophysically constrained chemistry of protein folding and the physiology of reproduction in all genera via amino acid substitutions and chromosomal rearrangements, which is what the octopus genome sequencing just showed.
Re: I just know this nonsense is going to be propagated by creationists everywhere, and I’m going to have to slam it down repeatedly.Thanks for acknowledging the fact you will be forced to address what is known to serious scientists about the link from microRNAs to biodiversity that refutes all claims of theorists about beneficial mutations.Jerome Hui and others linked all crustaceans to all insects via nutrient-dependent changes in the microRNA/messenger RNA balance. There is no reason to believe that anything else links marine invertebrates to primates.Besides, octopuses are referred to as the “primates of the sea.” The sequencing of the octopus genome links the conserved molecular mechanisms of biophysically constrained nutrient-dependent protein folding to RNA-mediated events and chromosomal rearrangements, which are clearly linked to all extant biodiversity without the nonsense about beneficial mutations and evolution.
Whenever you see “de novo” origin of a gene invoked, you know that evolutionary biologists lack any explanation for how that gene arose.”