Two hybrid systems were developed in Saccharomyces cerevisiae in 1989 and are still used extensively to screen for molecular interactions in the cell, including protein-protein, protein-DNA and protein-RNA interactions.

The 1980s saw a flurry of discovery in the field of eukaryotic transcriptional activation and cell biology. During this period, proteins were successfully expressed as fusions that retain their individual activities (1). Researchers also discovered the modular format of some transcriptional activators: that the DNA binding domain (DBD) and transcriptional activation (TA) domains retain their individual activities when separated (2), and that DBD and TAs from different systems could be combined effectively (3).

The second Boston Symposium on the Future of Research will be held from 22-24 October. This blog has been contributed by guest blogger and Future of Research Symposium organizer, David T. Riglar PhD. Here, Dr. Riglar discusses one of the six panel discussions to be held at the Future of Research Symposium Boston 2015 – Academic Data and the Labor Market. For more information on the symposium as a whole and for registration please go to http://futureofresearch.org/boston/.

This post was updated on Dec 5, 2017.

In 2015, Zetsche et al. added to the CRISPR toolbox with their characterization of two Cpf1 orthologs that display cleavage activity in mammalian cells. Like Cas9 nucleases, Cpf1 family members contain a RuvC-like endonuclease domain, but they lack Cas9’s second HNH endonuclease domain. Cpf1 cleaves DNA in a staggered pattern and requires only one RNA rather than the two (tracrRNA and crRNA) needed by Cas9 for cleavage. In certain cases, Cpf1 may be better suited for genome editing than Cas9 - read on to learn more about Cpf1 and check out our CRISPR guide for a refresher on CRISPR/Cas9. 

Every plasmid sample enters Addgene the same way. A package is delivered by a mail courier and then the journey of transformation and storage begins. Some samples are submitted as bacterial colonies in petri dishes, but close to 80% of samples are received as DNA in a microcentrifuge tube. Once a sample enters Addgene’s lab, a series of events is triggered. Each step is tracked through barcoded tubes that are scanned into our Laboratory Information Management System (LIMS), a database we use to keep track of and manage all of the samples that come through our doors. It would be a nightmare if we didn’t have a simple way to track all of our 40,000 samples available for distribution!

This post is part of our Primer on Optogenetics and was contributed by guest blogger Derek Simon.

The actual experiments you do will be determined by the topic you’re interested in studying, but, in today’s post, we’ll discuss some of the important considerations you should think about when developing optogenetics behavioral experiments. There are far too many behaviors that have utilized optogenetics to be fully summarized in a short blog post, but some examples I’m personally interested in include: intracranial self-stimulation (ICSS) and place preference. The lab I work in (the Kreek lab) focuses on the neurobiology of addictive diseases, which means we are interested in circuits that mediate drug taking behavior. If a circuit reinforces behavior (activation of the circuit promotes subsequent, repeated activation), this is an approximation of reward or the sense of pleasure that the animal perceives through taking a drug. The ideal behaviors to test reinforcement are ICSS and place preference.