Scientists develop molecular sensor to identify therapeutic drugs

Researchers have recently developed a molecular sensor which can identify cancer drugs by detecting how such chemicals modify microtubules inside living cells, said the Ministry of Science and Technology on Tuesday.

Microtubules are part of the cytoskeleton, a structural network within the cell’s cytoplasm, and they alter in response to several chemicals.

Understanding tubulin modifications has remained a challenge till date because of unavailability of tools that can mark them in living cells.

This work has been recently published in the Journal of Cell Biology.

The researchers from the Institute for Stem Cell Science and Regenerative Medicine (inStem) in Bengaluru and Curie Institute in France’s Orsay devised a method to design synthetic proteins known as nanobodies which can bind specifically to modified microtubules.

These nanobodies are similar to antibodies made in our body as a defence mechanism against pathogens. However, unlike antibodies, the nanobodies are smaller in size and easily amenable for protein engineering.

The nanobody was then coupled with a fluorescent molecule to serve as a detection tool called sensor.

They developed and validated a live cell sensor against a unique microtubule modification called tyrosinated form of microtubules that is already known to be important for cell division and intracellular organisation.

The tyrosination sensor is the first tubulin nanobody — or sensor — that could be used to study the dynamics of microtubule modifications in living cells.

These chemicals are frequently used as anti-cancer drugs. Thus, the tyrosination sensor would facilitate studying microtubule functions for many researchers and would aid identifying new drugs of therapeutic value.