Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Singapore scientists discover rejuvenation factors


Findings will advance our understanding of how cellular metabolism changes during aging and during rejuvenation after egg fertilisation.

Scientists from A*STAR’s Genome Institute of Singapore (GIS) have discovered metabolic rejuvenation factors in eggs. This critical finding furthers our understanding of how cellular metabolism changes during aging, and during rejuvenation after egg fertilisation.

Mitochondria during cellular aging. Copyright: A*STAR

When a sperm fertilises an egg to create a baby, two adult cells combine to form a new embryo. A similar process of combining an egg’s cytoplasm with an adult cell nucleus led to the cloning of Dolly the sheep. However, the metabolic factors underlying this fascinating process had remained unclear.

A new study from GIS suggests that old mitochondria – the oxygen-consuming metabolic engines in cells – are roadblocks to cellular rejuvenation. By tuning up a gene called Tcl1, which is highly abundant in eggs, researchers were able to suppress old mitochondria to enhance a process known as somatic reprogramming, which turn adult cells into embryonic-like stem cells.

GIS researchers found that Tcl1 does its job by suppressing mitochondrial polynucleotide phosphorylase, thereby inhibiting mitochondrial growth and metabolism.

Findings from the study were published in the scientific journal Cell Reports.

Stem cell researchers had known that egg (or oocyte) cytoplasm contains some special unknown factors that can reprogramme adult cells into embryonic-like stem cells, either during egg-sperm fertilisation or during artificial cloning procedures like those that created Dolly the sheep. While the Nobel Prize winner Dr Shinya Yamanaka had invented a technology called induced pluripotent stem cell (iPSC) reprogramming to replace the ethically controversial oocyte-based reprogramming technique, oocyte-based reprogramming was still deemed superior in complete cellular reprogramming efficiency.

To address this shortfall, the GIS team led by Dr Khaw Swea-Ling, Dr Lim Bing and Dr Ng Shyh-Chang combined oocyte factors with the iPSC reprogramming system. Their bioinformatics-driven screening efforts[1] led to two genes: Tcl1 and its cousin Tcl1b1. After a deeper investigation, the team found that the Tcl1 genes were acting via the mitochondrial enzyme, PnPase.

“We were quite surprised, because nobody would have thought that the key to the oocyte’s reprogramming powers would be a mitochondrial enzyme. The stem cell field’s conventional wisdom suggests that it should have been some other signalling genes instead,” said corresponding author of the research, Dr Ng Shyh-Chang.

Tcl1 is a cytoplasmic protein that binds to the mitochondrial enzyme PnPase. By locking PnPase in the cytoplasm, Tcl1 prevents PnPase from entering mitochondria, thereby suppressing its ability to promote mitochondrial growth and metabolism. Thus, an increase in Tcl1 suppresses old mitochondria’s growth and metabolism in adult cells, to enhance the somatic reprogramming of adult cells into embryonic-like stem cells.

Cracking the mystery of reprogramming factors in oocytes is an important milestone. These new insights could boost efficacy of the alternative, non-oocyte-based iPSC techniques for stem cell banking, organ and tissue regeneration, as well as further our understanding of how cellular metabolism rejuvenates after egg-sperm fertilisation. This could help address both the aging and the fertility problems of modern societies.

GIS Executive Director Prof Ng Huck Hui said, “This is an exciting step forward in the study of cellular aging. Although accumulated defects in mitochondrial metabolism were known to cause cellular aging, no solutions were available. Shyh-Chang’s team has uncovered a molecular pathway to solve this problem”.

[1] While the researchers attempted to deconstruct the mechanisms of oocyte-based reprogramming, no human oocytes or embryos were used or destroyed in the process as the screening effort was bioinformatics database-driven.

Associated links
Original press release from A*STAR

A*STAR Research | ResearchSea
Further information:

More articles from Life Sciences:

nachricht First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife

nachricht Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>