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Minor Spliceosomes as Real Time Sensors In Gene Regulation

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New researchout of the University of Pennsylvania reveals yet another fascinating aspect of gene expression regulation. In the higher species genes are not one continuous DNA segment. Instead there are intervening segments within genes known as introns (intervening regions). Many introns are quite long and some are short. After a gene is copied by the transcription machinery (known as RNA polymerase), resulting in an mRNA transcript, these major and minor introns are spliced out of the mRNA by the major and minor spliceosomes, respectively. The new research shows that the minor spliceosomes can be turned off, thus turning off the expression of that gene.  Read more

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Nobody would have a problem acknowledging that intelligence would be involved if someone retrieved a book from a library, copied a chapter from that book, removed sentences from it that were not pertinent to the use of the information for a specific purpose, then passed the remaining information to another agent. Yet evolutionists will argue endlessly that there is no intelligence involved is such mind-boggling complexity and interdependencies in the cell. Evolution theory is an embarrassment to science now that so much has been learned about biology since the 1950's when Crick put forth his central dogma statement. Evolutionists are like poor magicians expecting others to be amazed by their tricks, while the audience scratches their heads and asks if the magician is aware of the fact that his rabbit was seen being put into the hat.NephilimFree
August 26, 2013
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I just can't wait for the flock of Darwin Defenders to descend on this thread to start showing us how science proves the spliceosome evolved. Which came first, the intron, the exon, the major spliceosome or the minor splicesome?Mung
August 24, 2013
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Here is a simplified animation of the spliceosome in action:
RNA Splicing by the Spliceosome - video https://vimeo.com/70831358
Moreover, introns are turning out to be far more functionally important than the original junk DNA narrative that was told to us by Darwinists.
How 'Junk DNA' Can Control Cell Development - Aug. 2, 2013 Excerpt: Researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute have confirmed that, far from being "junk," the 97 per cent of human DNA that does not encode instructions for making proteins can play a significant role in controlling cell development.,, The researchers reached their conclusions through studying introns -- non-coding sequences which are located inside genes.,, http://www.sciencedaily.com/releases/2013/08/130802101900.htm
In fact the alternative splicing code itself was deciphered by considering the 'junk' intron sequences as functional:
Breakthrough: Second Genetic Code Revealed - May 2010 Excerpt: The paper is a triumph of information science that sounds reminiscent of the days of the World War II codebreakers. Their methods included algebra, geometry, probability theory, vector calculus, information theory, code optimization, and other advanced methods. One thing they had no need of was evolutionary theory,,, http://crev.info/content/breakthrough_second_genetic_code_revealed Canadian Team Develops Alternative Splicing Code from Mouse Tissue Data Excerpt: “Our method takes as an input a collection of exons and surrounding intron sequences and data profiling how those exons are spliced in different tissues,” Frey and his co-authors wrote. “The method assembles a code that can predict how a transcript will be spliced in different tissues.” http://www.genomeweb.com/informatics/canadian-team-develops-alternative-splicing-code-mouse-tissue-data
Moreover alternative splicing codes turn out to be 'species specific' i.e. the codes turn out to be drastically different between what are suppose to be closely related species:
Evolution by Splicing - Comparing gene transcripts from different species reveals surprising splicing diversity. - Ruth Williams - December 20, 2012 Excerpt: A major question in vertebrate evolutionary biology is “how do physical and behavioral differences arise if we have a very similar set of genes to that of the mouse, chicken, or frog?”,,, A commonly discussed mechanism was variable levels of gene expression, but both Blencowe and Chris Burge,,, found that gene expression is relatively conserved among species. On the other hand, the papers show that most alternative splicing events differ widely between even closely related species. “The alternative splicing patterns are very different even between humans and chimpanzees,” said Blencowe.,,, http://www.the-scientist.com/?articles.view%2FarticleNo%2F33782%2Ftitle%2FEvolution-by-Splicing%2F
What is particularly interesting in finding drastically different alternative splicing codes between closely related species is that drastically different alternative splicing codes between closely related species are far more difficult to explain the origination of than the ORFan genes are, (as extremely difficult as the ORFan genes are turning out to explain). The reason why drastically different splicing codes are more difficult to explain than ORFan genes is partially seen here:
“Because of Shannon channel capacity that previous (first) codon alphabet had to be at least as complex as the current codon alphabet (DNA code), otherwise transferring the information from the simpler alphabet into the current alphabet would have been mathematically impossible” Donald E. Johnson – Bioinformatics: The Information in Life Shannon Information - Channel Capacity - Perry Marshall - video http://www.metacafe.com/watch/5457552/
But Richard Dawkins himself gives us the most clear explanation as to why gradually changing only part of a code, and not implementing the entire code 'top down' all at once will be completely devastating for any gradual Darwinian scenario:
Venter vs. Dawkins on the Tree of Life - and Another Dawkins Whopper - March 2011 Excerpt:,,, But first, let's look at the reason Dawkins gives for why the code must be universal: "The reason is interesting. Any mutation in the genetic code itself (as opposed to mutations in the genes that it encodes) would have an instantly catastrophic effect, not just in one place but throughout the whole organism. If any word in the 64-word dictionary changed its meaning, so that it came to specify a different amino acid, just about every protein in the body would instantaneously change, probably in many places along its length. Unlike an ordinary mutation...this would spell disaster." (2009, p. 409-10) OK. Keep Dawkins' claim of universality in mind, along with his argument for why the code must be universal, and then go here (linked site listing 23 variants of the genetic code). Simple counting question: does "one or two" equal 23? That's the number of known variant genetic codes compiled by the National Center for Biotechnology Information. By any measure, Dawkins is off by an order of magnitude, times a factor of two. http://www.evolutionnews.org/2011/03/venter_vs_dawkins_on_the_tree_044681.html
The bottom line is that if any regulatory code, such as the genetic code, or the alternative splicing code, or the protein address code, or the acetylation code, or the metabolic code. or etc.. etc.. code, is ‘randomly changed’ in part, then it throws the entire code out of whack and will be ‘instantly catastrophic’, to use Richard Dawkins most appropriate term, thus rendering gradual change to a code impossible. The entire code must be implemented ‘top down’ when the species is created! There simply is no gradual pathway available to it. Music and verse:
Flyleaf - Fully Alive http://www.vevo.com/watch/flyleaf/fully-alive/USOCT0600148 Psalm 139:14-15 I praise you because I am fearfully and wonderfully made; your works are wonderful, I know that full well. My frame was not hidden from you when I was made in the secret place. When I was woven together in the depths of the earth,
bornagain77
August 24, 2013
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