Tracing the start of COVID-19 in GA

At a time when COVID-19 appears to be receding in much of Georgia, it’s worth revisiting the start of the pandemic in early 2020. Emory virologist Anne Piantadosi and colleagues have a paper in Viral Evolution on the earliest SARS-CoV-2 genetic sequences detected in Georgia. Analyzing relationships between those virus sequences and samples from other states and countries can give us an idea about where the first COVID-19 infections in Georgia came from. We can draw Read more

Reddit as window into opioid withdrawal strategies

Drug abuse researchers are using the social media site Reddit as a window into the experiences of people living with opioid addiction. Abeed Sarker in Emory's Department of Biomedical Informatics has a paper in Clinical Toxicology focusing on the phenomenon of “precipitated withdrawal,” in collaboration with emergency medicine specialists from Penn, Rutgers and Mt Sinai. Precipitated withdrawal is a more intense form of withdrawal that can occur when someone who was using opioids starts medication-assisted treatment Read more

CROI: HIV cure report and ongoing research

The big news out of CROI (Conference on Retroviruses and Opportunistic Infections) was a report of a third person being cured of HIV infection, this time using umbilical cord blood for a hematopoetic stem cell transplant. Emory’s Carlos del Rio gave a nice overview of the achievement for NPR this morning. As del Rio explains, the field of HIV cure research took off over the last decade after Timothy Brown, known as “the Berlin patient,” Read more

Tet enzymes

Vulnerability to stress – Tet by Tet

Geneticist Peng Jin and colleagues have a paper in Cell Reports this week that is part of a mini-boom in studying the Tet enzymes and their role in the brain. The short way to explain what Tet enzymes do is that they remove DNA methylation by oxidizing it out.

Methylation, a modification of DNA that generally shuts genes off, has been well-studied for decades. The more recent discovery of how cells remove methylation with the Tet enzymes opened up a question of what roles the transition markers have. It’s part of the field of epigenetics: the meaning of these modifications “above” the DNA sequence.

This is my favorite analogy to explain the transition states, such as 5-hydroxymethylcytosine. They’re not really a new letter of the genetic alphabet – they’ve been there all along. We just didn’t see them before.

Imagine that you are an archeologist, studying an ancient civilization. The civilization’s alphabet contains a limited number of characters. However, an initial pass at recently unearthed texts was low-resolution, missing little doodads like the cedilla in French: Ç.

Are words with those marks pronounced differently? Do they have a different meaning?

The new Cell Reports paper shows that it matters what pen writes the little doodads. In mice, removing one Tet enzyme, Tet1, has the opposite effect from removing Tet2, when it comes to response to chronic stress. One perturbation (loss of Tet1) makes the mice more resistant to stress, while the other (loss of Tet2) has them more vulnerable. The researchers also picked up an interaction between Tet1 and HIF1-alpha, critical for regulation of cells’ response to hypoxia. Read more

Posted on by Quinn Eastman in Neuro Leave a comment

Souped-up method for iPS cell reprogramming

Peng Jin and collaborators led by Da-Hua Chen from the Institute of Zoology, Chinese Academy of Sciences have a new paper in Stem Cell Reports. They describe a souped-up method for producing iPS cells (induced pluripotent stem cells).

Production of iPS cells in the laboratory is becoming more widespread. Many investigators, including those at Emory, are using the technology to establish “disease in a dish” models and derive iPS cells from patient donations, turning them into tools for personalized medicine research.

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Posted on by Quinn Eastman in Cancer, Immunology, Neuro Leave a comment