Research in the Filbin-Wong Lab revolves around determining the fundamental mechanisms of eukaryotic translation initiation and how these mechanisms are manipulated by viral pathogens and cellular development.
We are also interested in determining DNA detection limits in terms of forensic evidence.
Structure-Function of Non-coding RNAs
Non-coding RNAs (ncRNAs) are essential players in biology; they form the core of important cellular machines, they decode genetic information, they regulate gene expression and they functionally and structurally manipulate other macromolecules. Considering their varied roles, ncRNAs come in many different varieties, including ribosomal RNAs (rRNAs), transfer RNAs (tRNAs), micro RNAs (miRNAs) and a broad class of small/long non-coding RNAs. The role of rRNA and tRNA is fairly well defined as is the processing and function of miRNAs. However, the role of ncRNAs is still a major question in RNA biology. We are particularly interested in the role of viral ncRNAs as they are able to perform a wide array of functions in the absence of protein factors using specific RNA structures.
The specific family of ncRNAs we study are encoded in the 5′ and 3′ untranslated regions (UTRs) of viral genomic RNAs. These UTRs are capable of recruiting 80S ribosomes independent of the methylated guanosine cap structure found on the 5′ end of eukaryotic mRNAs, and often function in the absence of canonical translation initiation protein factors. Each virus has adapted to functionally replace the 5′ cap and host proteins factors via unique RNA structure-driven methods. By studying the structure-based mechanism of translation initiation, we aim to learn about fundamental mechanisms of eukaryotic translation initiation and the roles of ncRNAs in biology.
Regulation of Translation in Developing Neurons
The ribosome is the large, highly conserved, protein synthesis powerhouse of the cell. The enzymatic core of this machine is highly conserved across all domains of life, as is necessitated by the fundamental role of protein synthesis in all organisms. The surface of the ribosome, on the other hand, is less well conserved, which may be due in part to differences in regulation of the ribosome (and ribosomal subunits) in various organisms. We are interested in investigating regulation of the ribosome, specifically in response to chemotropism.
Neurons are highly polarized cells that develop directionally in response to chemotropic factors in their surrounding environment. Part of this response involves regulation of translation initiation at axonal growth cones – an extension of the developing neuron that will eventually form a synapse. In particular, ribosomes are held in an inactive state by the C-terminal tail of a transmembrane receptor highly expressed in the nervous system. Once this receptor binds its chemoattractant factor, ribosomes are released to commence protein synthesis. We are interested in how the C-terminal tail of this receptor binds the ribosome to render it inactive and whether or not the ribosome is primed to translate a message or initiates protein synthesis de novo once the extracellular signal is received. Much like the ncRNA project, these studies shed light on how the ribosome can be manipulated and hence furthers our understanding of the way in which this cellular machine functions.
Advancements in DNA extraction, quantification, amplification and sequencing are continuously altering standard techniques used in DNA forensics, particularly concerning detection sensitivity. In fact, detection of “touch DNA” is becoming a commonplace method for identifying a DNA profile from evidence or at the scene of a crime, and ultimately creating an investigative lead. Along with trace DNA, increased detection sensitivity raises the possibility of analyzing evidence that has been tampered with and extracting a useful amount of quality DNA. We are interested in identifying what limits detection of DNA and profile generation.
Common methods for tampering with biological evidence include covering stains with chemicals (e.g. bleach) or washing evidence in efforts to remove stains. There is little evidence of direct correlation between presumptive/confirmatory identification of evidence after cleaning and the quality of DNA profiles generated from these samples. We aim to determine what limits serological identification of biological fluids and whether or not these methods also limit DNA extraction and hence DNA profile generation.
Research in our lab is performed in collaboration with the lab of Dr. Jeffrey S. Kieft at the University of Colorado, Anschutz Medical Campus. We are always open to new collaborations to foster a rich experience for our undergraduates as well as continue exciting research. Please contact us if you are interested in a joint project!