Navigation Links
Penn biologists determine microRNA activity is suppressed in mouse ovum
Date:2/3/2010

PHILADELPHIA - Biologists at the University of Pennsylvania studying oocytes in mice, the immature egg cells necessary for sexual reproduction, have demonstrated an unusual behavior in microRNA, or miRNA, activity that may be the first event in reprogramming the differentiated oocyte into pluripotent blastomeres of the embryo. MicroRNAs are a member of the family of small RNAs, the so-called dark matter of the biological world.

MicroRNAs imperfectly pair with untranslated regions of RNA and mediate translational repression and mRNA degradationhallmarks of the gene expression process. The Dicer enzyme, which generates small RNAs in the miRNA and RNA interference pathways, is essential for meiotic maturation of mouse oocytes.

The scientists found that the mRNA population in oocytes lacking Dicer was not enriched in miRNA binding sites, implicating a weak impact of miRNAs on regulating mRNA stability. To explore further this possibility, the scientists injected a reporter transcript, a message RNA that is not a normally present in the oocyte but contained sequences that would interact with miRNAs in the oocyte. In somatic cells, such a message would be degraded and suppressed by micro RNA. However, in oocytes, there is minimal translational repression and no degradation of the message. The finding that this pathway does not operate in oocytes is most surprising because miRNAs are implicated in controlling cell differentiation.

The data, according to researchers, presents a puzzling paradox. "Although mouse oocytes produce miRNAs, their mRNA targets are poorly repressed," said Richard Schultz, associate dean for the natural sciences and the Charles and William L. Day Distinguished Professor of Biology in Penn's School of Arts and Sciences. "Reducing miRNA activity during oocyte growth may have two roles. First, the low activity of miRNA-mediated mRNA degradation, perhaps linked to the absence of P bodies (structures that are implicated as sites of miRNA-mediated mRNA degradation) may contribute to mRNA stability and accumulation of mRNA in growing oocytes. Second, down-regulation of the miRNA pathway may be required for oocyte-to-zygote transition."


'/>"/>

Contact: Jordan Reese
jreese@upenn.edu
215-573-6604
University of Pennsylvania
Source:Eurekalert

Related biology news :

1. CCNY biologists identify new spiny pocket mouse species
2. Penn biologists explain how organisms can tolerate mutations, yet adapt to environmental change
3. Biologists merge methods, results from different disciplines to find new meaning in old data
4. New handbook for biologists who need more competence or confidence in statistics
5. Biologists discover bacterial defense mechanism against aggressive oxygen
6. Beyond genomics, biologists and engineers decode the next frontier
7. Biologists, educators recognize excellence in evolution education
8. NIMBioS hosts tutorial on optimal control and optimization for biologists
9. Biologists discover death stench is a universal ancient warning signal
10. UTSA plant biologists publish where their peers are -- on the Web
11. Microbiologists find defense molecule that senses respiratory viruses
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/24/2017)... -- Janice Kephart , former 9/11 Commission ... LLP (IdSP) , today issues the following statement: ... 6, 2017 Executive Order: Protecting the Nation ... instilled with greater confidence, enabling the reactivation of ... are suspended by until at least July 2017). ...
(Date:4/17/2017)... MELBOURNE, Florida , April 17, 2017 ... security technology company, announces the filing of its 2016 Annual Report ... Securities and Exchange Commission. ... Report on Form 10-K is available in the Investor Relations section ... well as on the SEC,s website at http://www.sec.gov . ...
(Date:4/11/2017)... , April 11, 2017 Crossmatch®, ... secure authentication solutions, today announced that it has ... Advanced Research Projects Activity (IARPA) to develop next-generation ... program. "Innovation has been a driving ... Thor program will allow us to innovate and ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... ... Disappearing forests and increased emissions are the main causes of the evolving air ... living in larger cities are affected by air pollution related diseases. , That is ... globally - decided to take action. , “I knew I had to take action ...
(Date:10/10/2017)... DIEGO, CALIF. (PRWEB) , ... October 10, 2017 , ... ... as part of its corporate rebranding initiative announced today. The bold new look ... its reach, as the company moves into a significant growth period. , It will ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder and CEO of ... Club. The event entitled “Stem Cells and Their Regenerative Powers,” was ... Dr. Harman, DVM, MPVM was joined by two human doctors: Peter B. Hanson, M.D., ...
(Date:10/10/2017)... ... 10, 2017 , ... USDM Life Sciences , the ... sciences and healthcare industries, announces a presentation by Subbu Viswanathan and Jennifer Jaye ... GxP Validation for Agile Cloud Platforms,” will present a revolutionary approach to achieving ...
Breaking Biology Technology: