Cell biology of microtubules

Microtubules are also known as filamentous polymers. Microtubules play a role in the segregation of chromosomes and molecular transport. Research has been done to examine various lengths of microtubules in response to the changes of their proteins. Microtubules are outer cylinders that secure protofilaments consisting of tubulin proteins and serve as an intercellular transport network by providing mechanical stability.

Scientist, Erwin Frey, stated that as microtubules elongate, the greater the number of motor proteins will accommodate. These motor molecules are called kinesins, which proceed along the protofilament. Kinesin proteins move toward the positive end of the microtubule, while the motor protein moves toward the negative end. When the kinesin protein reaches the end, it detaches from the filament and takes the tubulin, thus allowing another tubulin to bind to the end. In certain ranges, the growth and shrinkage of the microtubules operates as it would if resources were not limiting. However, components and resources within a cell are unlikely to be available in unlimited amounts. Therefore, there is a certain length at which the rates of growth and shrinkage balance out.

Microtubules play an essential role in the cell, for they allow for the segregation of chromosomes. Having kinesin proteins allow for the microtubule to elongate and perform its function to the cell.

For additional information, refer to the original article.

For information on microtubules and protein functions, refer to link1 and article1.

Bionic Plants

Researchers from Linkoping University in Sweden have been able to successfully create a rose which is filled with electronic circuitry. The purpose of the study was to create a “smarter” breed of plant “which can respond to changes in its environment and let farmers know how it’s holding up”. The electronic circuitry would also allow the plant to boost its growth or bloom on command. Researchers in Sweden were able to create this bionic plant using a synthetic polymer called PEDOT-S. PEDOT-S was absorbed through the stems of the plants like nutrients. Once absorbed by the plant’s xylem, the PEDOT-S was assembled into conductive wire stretching up to 10 centimeters long. The researchers were then able to create working circuits using the plant’s own electrolytes. After the success of their first experiment, researchers plan to work with a whole array of “electronic greens” to further their studies. Researchers hope that these results will also be seen in edible plants which could greatly impact the farming industry, helping farmers create more resilient and bountiful crops.

This article was very interesting to read about. Prior to reading this article I had never heard of “bionic plants” or plants that have the ability to create electronic circuitry. I think that if the researchers are able to see the same results they saw in the roses in edible plants, it will be a huge break through.  If farmers had the ability to monitor their crops through electronic circuitry they would be able to grow stronger crops at a faster rate, thus increasing productivity and profits.

Here is another article about bionic plants.

Original Article

Neurodegeneration Linked To ADP-Ribose

In European news, EMBO.org (European Molecular Biology Organization) reports that researchers have identified an enzyme that removes ADP-ribose modifications from proteins by studying a genetic mutation that causes neurodegenerative disease in humans. These findings, suggest that not only addition but also removal of ADP-ribose from proteins is essential for normal cell function. Poly ADP-ribose or PARP chains play key roles in the repair of cellular DNA damage, and in the control of gene expression and cell death. Pharmacological drugs called PARP inhibitors prevent the addition of ADP-ribose or their polymers to proteins. Several of these drugs are undergoing clinical trials for the treatment of different types of cancers.

A breakthrough in the study came when collaborators from the National Institutes of Health, USA and Ludwig Maximilians University, Munich teamed up with clinical geneticists at the Human Genetics Research Center at St. George's University of London lead by Reza Sharifi. She stated,

“By studying genetic mutations in a group of patients with severe neurodegenerative disease, we found a gene that was mutated in a family that had several cases of severe progressive neurodegenerative and seizure disorder.”

She continued to explain that the product of this gene, named TARG1 (for terminal ADP-ribose protein glycohydrolase), exhibited the long-sought-after enzyme activity that fully removes ADP-ribose from proteins, and was further required for the rapid increase of cells and response to DNA damage.

The full research article can be found at The EMBO Journal.

If you read further into the linked articles it talks about how researchers found a gene that was mutated in a family that had several cases of severe progressive neurodegenerative and seizure disorder. The findings revealed that the attaching and removing chains of ADP-ribose to proteins are important to cell survivability and DNA repair. I find it simply amazing that they can analyze patients with a family history of neurodegeneration to gain a better understanding of this mechanism and perhaps give them a better understanding of what is happening to them and eventually, I believe, how to correct it. They are getting ever closer to finding out the exact enzyme(s) that may be responsible for it.