Close Menu
    Facebook X (Twitter) Instagram Pinterest YouTube LinkedIn TikTok
    TopBuzzMagazine.com
    Facebook X (Twitter) Instagram Pinterest YouTube LinkedIn TikTok
    • Home
    • Movies
    • Television
    • Music
    • Fashion
    • Books
    • Science
    • Technology
    • Cover Story
    • Contact
      • About
      • Amazon Disclaimer
      • Terms and Conditions
      • Privacy Policy
      • DMCA / Copyrights Disclaimer
    TopBuzzMagazine.com
    Home»Uncategorized»Study discovers cellular activity that hints recycling is in our
    Uncategorized

    Study discovers cellular activity that hints recycling is in our

    By July 11, 2024
    Facebook Twitter Pinterest LinkedIn Tumblr Email
    Study discovers cellular activity that hints recycling is in our

    Shown is the splicing pathway. The pre-messenger RNA (pre-mRNA) has exons (blue) and introns (pink). The spliceosome (not shown) was known to catalyze two chemical reactions (black arrows) in a two-step process (green arrows labeled 1 and 2) that splice the exons together and removes the intron as a lariat. This study demonstrates that after splicing is finished, the spliceosome is still active and can convert the lariat intron into a circle using a third reaction (green arrow 3) marked by an asterix. Credit: Manuel Ares, UC Santa Cruz

    Although you may not appreciate them, or have even heard of them, throughout your body, countless microscopic machines called spliceosomes are hard at work. As you sit and read, they are faithfully and rapidly putting back together the broken information in your genes by removing sequences called “introns” so that your messenger RNAs can make the correct proteins needed by your cells.

    Introns are perhaps one of our genome’s biggest mysteries. They are DNA sequences that interrupt the sensible protein-coding information in your genes, and need to be “spliced out.” The human genome has hundreds of thousands of introns, about 7 or 8 per gene, and each is removed by a specialized RNA protein complex called the “spliceosome” that cuts out all the introns and splices together the remaining coding sequences, called exons. How this system of broken genes and the spliceosome evolved in our genomes is not known.

    Over his long career, Manny Ares, UC Santa Cruz distinguished professor of molecular, cellular, and developmental biology, has made it his mission to learn as much about RNA splicing as he can.

    “I’m all about the spliceosome,” Ares said. “I just want to know everything the spliceosome does—even if I don’t know why it is doing it.”

    In a new paper published in the journal Genes and Development, Ares reports on a surprising discovery about the spliceosome that could tell us more about the evolution of different species and the way cells have adapted to the strange problem of introns. The authors show that after the spliceosome is finished splicing the mRNA, it remains active and can engage in further reactions with the removed introns.

    This discovery provides the strongest indication we have so far that spliceosomes could be able to reinsert an intron back into the genome in another location. This is an ability that spliceosomes were not previously believed to possess, but which is a common characteristic of “Group II introns,” distant cousins of the spliceosome that exist primarily in bacteria.

    The spliceosome and Group II introns are believed to share a common ancestor that was responsible for spreading introns throughout the genome, but while Group II introns can splice themselves out of RNA and then directly back into DNA, the “spliceosomal introns” that are found in most higher-level organisms require the spliceosome for splicing and were not believed to be reinserted back into DNA. However, Ares’s lab’s finding indicates that the spliceosome might still be reinserting introns into the genome today. This is an intriguing possibility to consider because introns that are reintroduced into DNA add complexity to the genome, and understanding more about where these introns come from could help us to better understand how organisms continue to evolve.

    Building on an interesting discovery

    An organism’s genes are made of DNA, in which four bases, adenine (A), cytosine (C), guanine (G) and thymine (T) are ordered in sequences that code for biological instructions, like how to make specific proteins the body needs. Before these instructions can be read, the DNA gets copied into RNA by a process known as transcription, and then the introns in that RNA have to be removed before a ribosome can translate it into actual proteins.

    The spliceosome removes introns using a two-step process that results in the intron RNA having one of its ends joined to its middle, forming a circle with a tail that looks like a cowboy’s “lariat,” or lasso. This appearance has led to them being named “lariat introns.” Recently, researchers at Brown University who were studying the locations of the joining sites in these lariats made an odd observation—some introns were actually circular instead of lariat shaped.

    This observation immediately got Ares’s attention. Something seemed to be interacting with the lariat introns after they were removed from the RNA sequence to change their shape, and the spliceosome was his main suspect.

    “I thought that was interesting because of this old, old idea about where introns came from,” Ares said. “There is a lot of evidence that the RNA parts of the spliceosome, the snRNAs, are closely related to Group II introns.”

    Because the chemical mechanism for splicing is very similar between the spliceosomes and their distant cousins, the Group II introns, many researchers have theorized that when the process of self-splicing became too inefficient for Group II introns to reliably complete on their own, parts of these introns evolved to become the spliceosome. While Group II introns were able to insert themselves directly back into DNA, however, spliceosomal introns that required the help of spliceosomes were not thought to be inserted back into DNA.

    “One of the questions that was sort of missing from this story in my mind was, is it possible that the modern spliceosome is still able to take a lariat intron and insert it somewhere in the genome?” Ares said. “Is it still capable of doing what the ancestor complex did?”

    To begin to answer this question, Ares decided to investigate whether it was indeed the spliceosome that was making changes to the lariat introns to remove their tails. His lab slowed the splicing process in yeast cells, and discovered that after the spliceosome released the mRNA that it had finished splicing introns from, it hung onto intron lariats and reshaped them into true circles. The Ares lab was able to reanalyze published RNA sequencing data from human cells and found that human spliceosomes also had this ability.

    “We are excited about this because while we don’t know what this circular RNA might do, the fact that the spliceosome is still active suggests it may be able to catalyze the insertion of the lariat intron back into the genome,” Ares said.

    If the spliceosome is able to reinsert the intron into DNA, this would also add significant weight to the theory that spliceosomes and Group II introns shared a common ancestor long ago.

    Testing a theory

    Now that Ares and his lab have shown that the spliceosome has the catalytic ability to hypothetically place introns back into DNA like their ancestors did, the next step is for the researchers to create an artificial situation in which they “feed” a DNA strand to a spliceosome that is still attached to a lariat intron and see if they can actually get it to insert the intron somewhere, which would present “proof of concept” for this theory.

    If the spliceosome is able to reinsert introns into the genome, it is likely to be a very infrequent event in humans, because the human spliceosomes are in incredibly high demand and therefore do not have much time to spend with removed introns. In other organisms where the spliceosome isn’t as busy, however, the reinsertion of introns may be more frequent. Ares is working closely with UCSC Biomolecular Engineering Professor Russ Corbett-Detig, who has recently led a systematic and exhaustive hunt for new introns in the available genomes of all intron-containing species that was published in the journal Proceedings of the National Academy of Sciences (PNAS) last year.

    The paper in PNAS showed that intron “burst” events far back in evolutionary history likely introduced thousands of introns into a genome all at once. Ares and Corbett-Detig are now working to recreate a burst event artificially, which would give them insight into how genomes reacted when this happened.

    Ares said that his cross-disciplinary partnership with Corbett-Detig has opened the doors for them to really dig into some of the biggest mysteries about introns that would probably be impossible for them to understand fully without their combined expertise.

    “It is the best way to do things,” Ares said. “When you find someone who has the same kind of questions in mind but a different set of methods, perspectives, biases, and weird ideas, that gets more exciting. That makes you feel like you can break out and solve a problem like this, which is very complex.”

    More information: Manuel Ares et al, Intron lariat spliceosomes convert lariats to true circles: implications for intron transposition, Genes & Development (2024). DOI: 10.1101/gad.351764.124

    Provided by University of California – Santa Cruz

    Citation: Study discovers cellular activity that hints recycling is in our DNA (2024, May 11) retrieved 10 July 2024 from https://phys.org/news/2024-05-cellular-hints-recycling-dna.html

    This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

    Read The Full Article Here

    Share. Facebook Twitter Pinterest LinkedIn Tumblr Email

    Related Posts

    Andrew Cole Guests On “If These Walls Could Talk” With Hosts Wendy Stuart and Tym Moss Wednesday, February 26th, 2025 

    February 23, 2025

    Award-Winning Comedian, Actor, LGBTQ Advocate Judy Gold Guests On Harvey Brownstone Interviews 

    October 29, 2024

    The 11 Bestselling Skims Products Everyone Wants

    August 4, 2024

    We Asked AI to Take Us On a Tour of

    August 4, 2024

    Listen to Two New SOPHIE Songs

    August 4, 2024

    College Students Can Get Max For 50% Off

    August 4, 2024
    popular posts

    A longevity diet that hacks cell ageing could add years

    We Need 50 More Years of the Clean Water Act

    Al Michaels to Call ‘Thursday Night Football’ for Amazon Prime

    ‘No Demo Reno’ Star Jenn Todryk on Why Season 3

    The Summer I Turned Pretty Season 2 Begins on an

    Fluid dynamics researchers shed light on how partially submerged objects

    Elon Musk’s SpaceX Gets Approval to Use Starlink Satellite Internet

    Categories
    • Books (3,297)
    • Cover Story (5)
    • Events (19)
    • Fashion (2,457)
    • Interviews (43)
    • Movies (2,596)
    • Music (2,875)
    • News (155)
    • Politics (2)
    • Science (4,446)
    • Technology (2,589)
    • Television (3,319)
    • Uncategorized (932)
    Archives
    Facebook X (Twitter) Instagram Pinterest YouTube Reddit TikTok
    © 2025 Top Buzz Magazine. All rights reserved. All articles, images, product names, logos, and brands are property of their respective owners. All company, product and service names used in this website are for identification purposes only. Use of these names, logos, and brands does not imply endorsement unless specified. By using this site, you agree to the Terms of Use and Privacy Policy.

    Type above and press Enter to search. Press Esc to cancel.

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept”, you consent to the use of ALL the cookies.
    Do not sell my personal information.
    Cookie SettingsAccept
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
    CookieDurationDescription
    cookielawinfo-checkbox-analytics11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
    cookielawinfo-checkbox-functional11 monthsThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
    cookielawinfo-checkbox-necessary11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
    cookielawinfo-checkbox-others11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
    cookielawinfo-checkbox-performance11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
    viewed_cookie_policy11 monthsThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
    Functional
    Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
    Performance
    Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
    Analytics
    Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
    Advertisement
    Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
    Others
    Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.
    SAVE & ACCEPT