January 26, 2011
By: by Janet Paluh, CNSE Associate Professor of Nanobioscience
Nanobioscience is the driving force behind observation, identification, modeling and translation of nanoscale phenomena occurring at single and multi-cellular scales into next generation technologies applicable to manufacturing and medicine.
Within eukaryotic cells nanoscale networks have been fine tuned for over 3.5 billion years. To biomimic such perfection we are learning how cellular nanomachines coordinate to physically assemble structures and drive processes. This includes revealing the underlying nanonetworks of communication, what design principles operate for flexible architectures, and how events are executed, controlled, evaluated for success and error corrected.
A key element to the dynamic infrastructure of cells is the microtubule cytoskeleton. Microtubules on the scale of 25nm diameter can be crosslinked, bundled and organized into a variety of structures that enable compartmentalization, signaling, transport and force generation. The microtubule cytoskeleton has an impressive extent of influence. It is critical to chromosome segregation, cell division, directed motility, neural networks, ciliary functions and cell fate decisions for multiple developmental pathways. This makes microtubule assemblies some of the most important known structures capable of bridging nano and macroscale events.
A pervasive element to nanoassemblies is that their highly sensitive, responsive, nonrigid format. Microtubules themselves are inherently dynamic, essentially poised to respond. The identification of a microtubule nanomotor, Kinesin, twenty five years ago opened the door to discovery of an armory of nanoscale machines that use chemical energy to mediate microtubule events, including tethering objects that outsize them 100 fold. At least 14 families of kinesin-like proteins (Klps) exist, each with added diversity amongst members that is evident in functional elements of Tail, Stalk, Neck and Motor domains. Perhaps fastest is the kinesin motor itself, capable of traveling 800 nm/sec along a microtubule protofilament in one hundred 8 nm steps. In terms of the macroscale dimensions in which we live, this amazing motor applies speed and horsepower per unit weight that is comparable to the jet engine on a supersonic car. It is no surprise that these motor proteins are integrated at multiple levels into microtubule function, including regulation of the microtubule-synthesizing machine itself in cells, the microtubule organizing center.
Henry Ford once said that "nothing is particularly hard if you divide it into small jobs", and indeed that "there are no big problems, there are just lots of little problems." Clearly in cells a multitude of molecular machines has been assembled to address individual cellular needs. Research into nanorobotics at the College of Nanoscale Science and Engineering (CNSE) of the University at Albany includes not only motor proteins and microtubules, but also a comprehensive evaluation of molecular machines. Redirecting nanonetworks to function outside of the cellular context and in new processes will require engineering in new functions that can integrate with nontraditional manmade components.
The ability to study cells in artificial environments over the past 50 years has had a tremendous impact on medical discoveries. Over the past decade our understanding of how environments impact cell behavior has undergone an extensive re-education provided by stem cells. An incredible reprogramming potential exists in cells that is not limited to the embryonic state. This means it is ever more critical to faithfully recapitulate the multi-cellular environment in terms of chemical gradients and signaling molecules, surface tension and topology, cellular context and even oxygen level. A major challenge in designing complex 3D tissue architectures in vitro is the ability to integrate neural and vascular networks. Research is underway towards this end. The payoff is enormous in terms of the potential to repair or replace damaged tissues and organs and dramatically impact the quality of human life.
At CNSE, a multi-disciplinary strategy is revealing new insights into nanonetworks at cellular and multi-cellular levels that will allow us to overcome traditional barriers in order to generate groundbreaking discoveries.Dr. Paluh's bio