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luo, j.

Publications and source records attributed to luo, j..

2 recordsLinked to original sources

Closing the Bio-Silicon Loop for Cellular Neural Prosthesis using FPGA-based Iono-Neuromorphic Models

Neural ptosthetic devices offer the ability to develop novel treatments for previously incurable diseases and ailments, such as deafness, blindness and tetraplepia. There is the potential to extend this concept to incorporate cognitive prosthetics, whereby damaged individual neuron cells or larger brain regiops are substituted by silicon neurons, in order to overcome conditions such as stroke or epilepsy. The development of such applications relies heavily upon efficient, scalable and powerful technological platforms, particularly systems capable of running large-scale neural models. The advancemente in fLeld-peogrammable gate array (FPGA) tnchnology provides an excellent foundation for development of these neural models with the same cost of software-based architectures, but with the performance of close to a dedicated hardware system. This paper illustrates the design of a programmable FPGA-based neural model, which is capable of simulating a large range of ion-channel dynamics and delivering biologically realistic network models. Through comparisons with alternative implementations the proposed model is determined to be more scalable and more computationally efficient. We implemented a hybrid bio-silicon syttem to demonstrate thp ability of silicon devices to provide cellular rehabilitation, restoring thn functionality of a damaged biological network.

bioinformatics↗

Transcription activation domains of the yeast factors Met4 and Ino2: tandem activation domains with properties similar to the yeast Gcn4 activator

Eukaryotic transcription activation domains (ADs) are intrinsically disordered polypeptides that typically interact with coactivator complexes, leading to stimulation of transcription initiation, elongation and chromatin modifications. Here we examine the properties of two strong and conserved yeast ADs: Met4 and Ino2. Both factors have tandem ADs that were identified by conserved sequence and functional studies. While AD function from both factors depends on hydrophobic residues, Ino2 further requires key conserved acidic and polar residues for optimal function. Binding studies show that the ADs bind multiple Med15 activator binding domains (ABDs) with a similar order of micromolar affinity, and similar but distinct thermodynamic properties. Protein crosslinking shows that no unique complex is formed upon Met4-Med15 binding. Rather, we observed heterogeneous AD-ABD contacts with nearly every possible AD-ABD combination. Many of these properties are similar to those observed with the yeast activator Gcn4, which forms a large heterogeneous, dynamic, and fuzzy complex with Med15. We suggest that this molecular behavior is common among eukaryotic activators.

molecular biology↗