Research Highlights

• Sarah A. Kessans, Mark D. Linhart, Nobuyuki Matoba, Tsafrir Mor (2013) Biological and biochemical characterization of HIV-1 Gag/dgp41 virus-like particles expressed in Nicotiana benthamiana. Plant Biotechnology Journal (2013), pp. 1-10: e1002154. doi:10.1111/pbi.12058
  
  

  The transmembrane HIV-1 envelope protein gp41 has been shown to play critical roles in the viral mucosal transmission and infection of CD4+ cells. Gag is a structural protein configuring the enveloped viral particles and has been suggested to constitute a target of the cellular immunity that may control viral load. We hypothesized that HIV enveloped virus-like particles (VLPs) consisting of Gag and a deconstructed form of gp41 comprising the membrane proximal external, transmembrane and cytoplasmic domains (dgp41) could be expressed in plants. To this end, plant-optimized HIV-1 genes were constructed and expressed in Nicotiana benthamiana by stable transformation, or transiently using a Tobamovirus-based expression system or a combination of both. Our results of biophysical, biochemical and electron microscopy characterization demonstrates that plant cells could support not only the formation of enveloped HIV-1 Gag VLPs, but also the accumulation of VLPs that incorporated dgp41. These findings provide further impetus for the journey towards a broadly efficacious and inexpensive subunit vaccine against HIV-1.
  (Currently in press)

Previous Highlights

• Z. Nevin Gerek & S. Banu Ozkan (2011) Change in allosteric network affects binding affinities of PDZ Domains: Analysis through Perturbation Response Scanning. PLoS Computational Biology 7(10): e1002154. doi:10.1371/journal.pcbi.1002154
  
  

  Allostery plays a key role in the regulation of the activity and function of many biomolecular systems including membrane proteins. It is very critical to have knowledged how allosteric transition occurs. A new computational approach towards this goal will be published in the scientific journal PLoS Computational Biology. The study is focused on the allosteric response of PDZ domains, the most common interaction domain proteins found in organisms from bacteria to humans, which play critical roles in organizing functional protein complexes and controlling cellular activities through allosteric regulations. They also interact with membrane and membrane proteins. Many challenging diseases such as Alzheimer’s, Parkinson’s, and breast cancer are linked with PDZs. It is proposed that these diseases can be cured by controlling the binding of PDZ domain proteins. Therefore, it is very important to explore how dynamic interactions of residues within PDZ domain fold and play an important role in allosteric regulation.
  PLoS Computational Biology Website >>

• Experiment reaches biology milestone with hard X-ray laser.
  
  

  Unraveling the molecular basis of life is a long-standing quest of humanity. A breakthrough towards this goal was reported in a pair of studies published Feb. 3 in the scientific journal Nature, detailing a new method developed to determine structures of biomolecules based on diffraction from protein nanocrystals that are so small that they are not even visible under the microscope.
  ASU News >>