Engineered “stealth bomber” virus could be new weapon against metastatic cancer

Researchers at Emory and Case Western Reserve have re-engineered a cancer-killing virus, so that it is not easily caught by parts of the immune system. Read more

Another side to cancer immunotherapy? Emory scientists investigate intratumoral B cells

B cells represent the other major arm of the adaptive immune system, besides T cells, and could offer opportunities for new treatments against some kinds of Read more

Don’t go slippery on me, tRNA

RNA can both carry genetic information and catalyze chemical reactions, but it’s too wobbly to accurately read the genetic code by itself. Enzymatic modifications of transfer RNAs – the adaptors that implement the genetic code by connecting messenger RNA to protein – are important to stiffen and constrain their interactions. Biochemist Christine Dunham’s lab has a recent paper in eLife showing a modification on a proline tRNA prevents the tRNA and mRNA from slipping out Read more

viral RNA polymerase

Super-cold technique = hot way to see enzyme structure

In the last decade, a revolution has been taking place in structural biology, the field in which scientists produce detailed maps of how enzymes and other machines in the cell work. That revolution is being driven by cryo-electron microscopy (cryo-EM for short), which is superseding X-ray crystallography as the main data-production technique and earned a chemistry Nobel in 2017.

Just before COVID-19 sent some Emory researchers home and drove others to pivot their work toward coronavirus, Lab Land had a chance to tour the cryo-EM facility and take photos, with the help of Puneet Juneja, director of the core. Juneja demonstrated how samples are prepared for data collection — see the series of photos below.

Someone coming into the facility in the Biochemistry Connector area will notice a sign telling visitors and those passing by to stay quiet (forgot to take a photo of that!). The facility has electrical shielding and temperature/humidity controls. Also two levels of cooling are required for samples, since they are flash-frozen or “vitrified” in liquid ethane, which is in turn cooled by liquid nitrogen. The cooling needs to happen quickly so that ice crystals do not form. The massive cryo-EM equipment rests on a vibration-reduction platform; no music and no loud conversation are allowed during data collection.

One of the first structures obtained in this relatively new facility was the structure of a viral RNA polymerase, the engine behind viral replication. It wasn’t a coronavirus enzyme – it was from RSV (respiratory syncytial virus).

Still, cryo-EM is a way to visualize exactly how drugs that inhibit the SARS-CoV-2 polymerase – such as remdesivir or Emory’s own EIDD-2801 – exert their effects. Chinese researchers recently published a cryo-EM structure of the SARS-CoV-2 polymerase with remdesivir in Science. Read more

Posted on by Quinn Eastman in Immunology, Uncategorized Leave a comment