The adult human body consists of trillions of cells. Cell proliferation is accomplished by means of cell division in which an existing cell serves as the exact blueprint for its progeny. This process follows the same basic principles in all higher organisms. First, the genetic information is precisely copied and subsequently equally distributed between the mother and daughter.
Dividing human cancer cell in Metaphase. The DNA (gray) is attached to the spindle apparatus (pseudocolored). Copyright: IMP/Ladurner
The major task for the dividing cell is to drag two complete sets of chromosomes to the opposite sides of the nucleus, respectively. A logistic challenge accomplished by the interplay of two factors: the spindle apparatus that acts as the molecular motor driving chromosome movements, and the kinetochore that constitutes the physical platform between the DNA and the mitotic spindle.
The attachment site formed by the kinetochore is an intricate protein network. While its components providing the direct contact point for the spindle are very well preserved from yeast to human, evolution of the DNA-binding proteins remained puzzling given that the underlying DNA template is highly variable.
Now, a novel study published in the June edition of Nature Cell Biology sheds light onto the cryptic molecular relationship between the yeast and human kinetochore. Principal investigator Stefan Westermann and his team tracked the missing evolutionary link and opened up new insights into the architecture and function of the key division organelle.
The correct shape pieces the puzzle together
“The clue was to take a close look at the protein sequence as well as specific sequence motifs that get an amino acid chain into its particular shape.” says Stefan Westermann. “In this way, our bioinformatician Alexander Schleiffer was able to predict a number of novel DNA-binding kinetochore proteins and assigned them to the respective human homolog.” Follow-up experiments strongly supported analogous function of the proteins. “Yeast is still an informative model organism and very easy to handle. Our current findings can now direct similar studies in more complex systems. There erroneous chromosome segregation is deleterious for the cell and a common cause of cancer” explains the scientist.
Dr. Heidemarie Hurtl | idw
Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences