Corporate Banner
Satellite Banner
Scientific Communities
Become a Member | Sign in
Home>News>This Article

“Junk DNA” Drives Embryonic Development

Published: Thursday, December 06, 2012
Last Updated: Thursday, December 06, 2012
Bookmark and Share
An embryo is an amazing thing. From just one initial cell, an entire living, breathing body emerges, full of working cells and organs.

It comes as no surprise that embryonic development is a very carefully orchestrated process—everything has to fall into the right place at the right time. Developmental and cell biologists study this very thing, unraveling the molecular cues that determine how we become human.

“One of the first, and arguably most important, steps in development is the allocation of cells into three germ layers—ectoderm, mesoderm, and endoderm—that give rise to all tissues and organs in the body,” explains Mark Mercola, Ph.D., professor and director of Sanford-Burnham’s Muscle Development and Regeneration Program in the Sanford Children’s Health Research Center.

In a study published November 14 in the journal Genes & Development, Mercola and his team, including postdoctoral researcher Alexandre Colas, Ph.D., and Wesley McKeithan, discovered that microRNAs play an important role in this cell- and germ layer-directing process during development.

MicroRNA: one man’s junk is another’s treasure

MicroRNAs are small pieces of genetic material similar to the messenger RNA that carries protein-encoding recipes from a cell’s genome out to the protein-building machinery in the cytoplasm.  Only microRNAs don’t encode proteins. So, for many years, scientists dismissed the regions of the genome that encode these small, non-protein coding RNAs as “junk.”

We now know that microRNAs are far from junk. They may not encode their own proteins, but they do bind messenger RNA, preventing their encoded proteins from being constructed. In this way, microRNAs play important roles in determining which proteins are produced (or not produced) at a given time.

MicroRNAs are increasingly recognized as an important part of both normal cellular function and the development of human disease.

So, why not embryonic development, too?

Directing cellular traffic

To pinpoint which—if any—microRNAs influence germ layer formation in early embryonic development, Mercola and his team individually studied most (about 900) of the microRNAs from the human genome. They tested each microRNA’s ability to direct formation of mesoderm and endoderm from embryonic stem cells. In doing so, they discovered that two microRNA families—called let-7 and miR-18—block endoderm formation, while enhancing mesoderm and ectoderm formation.

The researchers confirmed their finding by artificially blocking let-7 function and checking to see what happened. That move dramatically altered embryonic cell fate, diverting would-be mesoderm and ectoderm into endoderm and underscoring the microRNA’s crucial role in development.

But they still wanted to know more…how do let-7 and miR-18 work? Mercola’s team went on to determine that these microRNAs direct mesoderm and ectoderm formation by dampening the TGFβ signaling pathway. TGFβ is a molecule that influences many cellular behaviors, including proliferation and differentiation. When these microRNAs tinker with TGFβ activity, they send cells on a certain course—some go on to become bone, others brain.

“We’ve now shown that microRNAs are powerful regulators of embryonic cell fate,” Mercola says. “But our study also demonstrates that screening techniques, combined with systems biology, provide a paradigm for whole-genome screening and its use in identifying molecular signals that control complex biological processes.”

Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,500+ scientific posters on ePosters
  • More Than 5,100+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Sanford-Burnham to Partner with Pfizer
The collaboration will see the organisations identify new therapeutic targets for preventing and treating complications of obesity and diabetes.
Tuesday, August 20, 2013
A Cautionary Tale on Genome-Sequencing Diagnostics for Rare Diseases
Studies in several children have raising new questions about inheritance, genomic sequencing, and diagnostic.
Tuesday, May 14, 2013
Scientific News
Integrated Omics Analysis
Studying multi-omics promises to give a more holistic picture of the organism and its place in its ecosystem, however despite the complexities involved those within the field are optimistic.
Unravelling the Role of Key Genes and DNA Methylation in Blood Cell Malignancies
Researchers from the University of Nebraska Medical Center have demonstrated the role of Dnmt3a in safeguarding normal haematopoiesis.
Salford Lung Study - The First Real World Clinical Trial
In this podcast, we learn about the Salford Lung Study and its potential to revolutionize the way we assess new drugs and treatments around the world.
Point of Care Diagnostics - A Cautious Revolution
Advances in molecular biology, coupled with the miniaturization and improved sensitivity of assays and devices in general, have enabled a new wave of point-of-care (POC) or “bedside” diagnostics.
Mass Spec Technology Drives Innovation Across the Biopharma Workflow
With greater resolving power, analytical speed, and accuracy, new mass spectrometry technology and techniques are infiltrating the biopharmaceuticals workflow.
Structure of Primary Cannabinoid Receptor is Revealed
The findings provide key insights into how natural and synthetic cannabinoids including tetrahydrocannabinol —a primary chemical in marijuana—bind at the CB1 receptor to produce their effects.
Overlooked Molecules Could Revolutionise our Understanding of the Immune System
Researchers have discovered that around one third of all the epitopes displayed for scanning by the immune system are a type known as ‘spliced’ epitopes.
Illumina Contributes to ClinVar Database
The contribution includes variants of all classifications, from pathogenic to benign, identified during interpretation of whole genome sequences generated in the CLIA-certified, CAP-accredited Illumina Clinical Services Laboratory.
Agilent Presents Early Career Professor Award to Dr. Roeland Verhaak
JAX professor recognized for the development and implementation of workflows for the analysis of big-data from transcriptomics to next generation sequencing approaches.
NIH Study Determines Key Differences between Allergic and Non-Allergic Dust Mite Proteins
Researchers at NIH have uncovered factors that lead to the development of dust mite allergy and assist in the design of better allergy therapies.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,500+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
5,100+ scientific videos