From macrophages that seek out and destroy infectious agents to fibroblasts that hold tissues and organs together, cells give form and function to our bodies. However, despite their foundational roles in our biology, there is still much we don’t know about cells—like where different cell types are localized, what states a given cell type may take on, how the molecular characteristics of cells change over a person’s lifetime and more. Addressing these questions will provide a deeper understanding about the cellular and genetic basis of human health and disease.Continue reading “The Human Cell Atlas: Mapping a Cellular Landscape”
RNA-Protein Interactions: A New Frontier for Drug Discovery
Almost 90% of the human genome is transcribed into RNA, but only 3% is ultimately translated into a protein. Some non-translated RNA is thought to be useless, while some play a significant yet often mysterious role in cancer and other diseases. Despite its abundance and biological significance, RNA is rarely the target of therapeutics.
“We say it’s undruggable, but I would say that ‘not-yet-drugged’ is a better way to put it,” says Amanda Garner, Associate Professor of Medicinal Chemistry at the University of Michigan. “We know that RNA biology is important, but we don’t yet know how to target it.”
Amanda’s lab develops systems to study RNA biology. She employs a variety of approaches to analyze the functions of different RNAs and study their interactions with proteins. Her lab recently published a paper describing a novel method for studying RNA-protein interactions (RPI) in live cells. Amanda says that with the right tools, RPI could become a critical target for drug discovery.
“It’s amazing that current drugs ever work, because they’re all based on really old approaches,” Amanda says. “This isn’t going to be like developing a small molecule kinase inhibitor. It’s a whole new world.”Continue reading “RNA-Protein Interactions: A New Frontier for Drug Discovery”
Buckling Down to Scale Up: Providing Support Through the Pandemic
The past year has been a challenge. Amidst the pandemic, we’re thankful for the tireless work of our dedicated employees. With their support, we have continuously stayed engaged and prepared during all stages of the COVID-19 pandemic so that we can serve our customers at the highest levels.
How We Got Here
The persistent work by our teams has made a great impact on the support we can provide for scientists and our community during the pandemic. From scaling up manufacturing to investing in new automation, every effort has helped.
Promega has a long history of manufacturing reagents, assays, and benchtop instruments for both researching and testing viruses. When the pandemic began in 2020, we responded quickly and efficiently to unprecedented demands. In the past year, we experienced an approximately 10-fold increase in demand for finished catalog and custom products for COVID-19 testing. In response to these demands, we increased production lines. One year ago, we ran one shift five days per week. Currently, we run three shifts seven days per week. This change has allowed 50 different Promega products to support SARS-CoV-2 testing globally in hospitals, clinical diagnostic laboratories, and molecular diagnostic manufacturers. Additionally, our clinical diagnostics materials make up about 2/3 of COVID-19 PCR tests on the global market today. Since January 2020, Promega has supplied enough reagents to enable testing an estimated 700 million samples for SARS-CoV-2 worldwide.
Developments and Advances
Promega products are used in viral and vaccine research. This year, our technologies have been leveraged for virtually every step of pandemic response from understanding SARS-CoV-2 to testing to research studies looking at vaccine response.
- Products in the US Centers for Disease Control (CDC) Influenza SARS-CoV-2 (Flu SC2) Multiplex Assay for emergency use: Maxwell® RSC 48 and CSC 48 instruments; Maxwell® RSC Viral Total Nucleic Acid Purification Kit
- Products in the CDC 2019-Novel Coronavirus Real-Time RT-PCR Diagnostic Panel for emergency use: GoTaq® Probe 1-Step RT-qPCR System; Maxwell® RSC 48 and CSC 48 instruments; Maxwell® RSC Viral Total Nucleic Acid Purification Kit
- The Lumit™ SARS-CoV-2 Immunoassay to detect antibodies to SARS-CoV-2 in research studies.
- XpressAmp™ Direct Amplification Reagents enable direct amplification of viral nucleic acid from samples without RNA extraction.
- Promega developed a SARS-CoV-2 RT-qPCR Kit for Wastewater to provide a surveillance approach to get ahead of COVID-19 progression in a community.
Who Got Us Here
We are extremely grateful for our employees. In the past year, we hired over 100 people and still have positions open today. While welcoming newcomers, this challenging year also reinforced the importance of our collaborative culture. Relationships at Promega have been built over multiple years. The long history of our teams allows us to stay coordinated while prioritizing product distribution to customers across the globe. It also leads to effective communication with colleagues and vendors. Those leading our manufacturing operations team, for example, have an average tenure of 15 years. Their history in collaborating through challenging situations helps them quickly focus where needed most.
Our 600 on-site employees support product manufacturing, quality, and R&D. They do it all while remaining COVID-conscious by social distancing, wearing masks, working split shifts, and restricting movement between buildings. While we continue to practice physical safety precautions, we also prioritize our employees’ mental health and wellness. Promega provides a variety of wellness resources including phone and video mental health sessions, virtual fitness and nutrition classes, and stress and anxiety tools.
What’s to Come
While we acknowledge that the COVID-19 is not over, we are proud of the support we have been able to provide to customers working both on pandemic research and critical research not related to COVID-19. Our policies of long-term planning and investing in the future has allowed us to respond quickly and creatively and learn from the experience.
High-Throughput Purification with Experts Included
Implementing automated nucleic acid purification or making changes to your high-throughput (HT) workflow can be complicated and time-consuming. There are also many barriers to success such as challenging samples types and maintaining desirable downstream results that can add to the stress, not to mention actually getting the robotic instrumentation to do what you want it to. All of this makes it easy to understand why many labs avoid automating or own expensive instrumentation that goes unused. Continue reading “High-Throughput Purification with Experts Included”
A Crash Course in CRISPR
CRISPR is a hot topic right now, and rightly so—it is revolutionizing research that relies on editing genes. But what exactly is CRISPR? How does it work? Why is everyone so interested in using it? Today’s blog is a beginner’s guide on how CRISPR works with an overview of some new applications of this technology for those familiar with CRISPR.
Introduction to CRISPR/Cas9
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) were discovered in 1987, but it took 30 years before scientists identified their function. CRISPRs are a special kind of repeating DNA sequence that bacteria have as part of their “immune” system against invading nucleic acids from viruses and other bacteria. Over time, the genetic material from these invaders can be incorporated into the bacterial genome as a CRISPR and used to target specific sequences found in foreign genomes.
CRISPRs are part of a system within a bacterium that requires a nuclease (e.g. Cas9), a single guide RNA (sgRNA) and a tracrRNA. The tracrRNA recruits Cas9, while sgRNA binds to Cas9 and guides it to the corresponding DNA sequence of the invading genome. Cas9 then cuts the DNA, creating a double-stranded break that disables its function. Bacteria use a Protospacer Adjacent Motif, or PAM, sequence near the target sequence to distinguish between self and non-self and protect their own DNA.
While this system is an effective method of protection for bacteria, CRISPR/Cas9 has been manipulated in order to perform gene editing in a lab (click here for a video about CRISPR). First, the tracrRNA and sgRNA are combined into a single molecule. Then the sequence of the guide portion of this RNA is changed to match the target sequence. Using this engineered sgRNA along with Cas9 will result in a double-stranded break (DSB) in the target DNA sequence, provided the target sequence is adjacent to a compatible PAM sequence.Continue reading “A Crash Course in CRISPR”
How to Isolate RNA like a Pro
Back in graduate school, I purified a lot of RNA, and after a while, I became fairly successful at it. My yields were good, and the RNA was intact. However, many of my early attempts at RNA isolation yielded degraded RNA that did not work well in many downstream applications. In my case, successfully isolating high-quality RNA required practice. During my trials and tribulations, I learned a lot of tricks and tips about how to obtain high-quality RNA. Here I share some of these tricks to help you speed through that “practice makes perfect” phase so that you can isolate RNA like a pro.
Methods for Quantitating Your Nucleic Acid Sample
For most molecular biology applications, knowing the amount of nucleic acid present in your purified sample is important. However, one quantitation method might serve better than another, depending on your situation, or you may need to weigh the benefits of a second method to assess the information from the first. Our webinar “To NanoDrop® or Not to NanoDrop®: Choosing the Most Appropriate Method for Nucleic Acid Quantitation” given by Doug Wieczorek, one of our Applications Scientists, discussed three methods for quantitating nucleic acid and outlined their strengths and weaknesses. Continue reading “Methods for Quantitating Your Nucleic Acid Sample”
Don’t Let Ribonucleases Ruin Your Week(end): Establish a Ribonuclease-free Environment
My very first job in science was in a lab that worked exclusively with RNA, and it was only after I moved on to a different job that I learned just how much different the world of DNA research is from that of RNA. When working with DNA, for example, you rarely if ever have the sample you have labored over reduced to a fuzzy blur at the bottom of a gel because it has been degraded beyond rescue. With RNA, unfortunately, this happens all too frequently. In fact, a labmate of mine once put up a poll on the door to our lab asking if it was better to discover that your RNA sample was degraded on a Monday or a Friday.
The culprits in this scenario are Ribonucleases (RNases). They are everywhere. They are incredibly stable and difficult to inactivate. And, if you work with RNA, they are your enemy. Take heart though, they can be defeated if you follow some pretty simple steps.Continue reading “Don’t Let Ribonucleases Ruin Your Week(end): Establish a Ribonuclease-free Environment”
Working with RNA
Working with RNA can be a tricky thing…it falls apart easily, and RNases (enzymes that degrade RNA) are ubiquitous. Successfully isolating RNA and maintaining its integrity is critical, especially when sensitive downstream applications are used (e.g., RNA-Seq).
Good techniques for RNA handling are simple to employ but crucial for success. All RNA purification and handling should take place in an RNase-free, RNA-only zone of the lab. Segregating RNA work from protein and DNA purification and handling will help minimize the potential for RNase contamination and help keep your RNA intact. Only buffer and water stocks treated to be RNase-free should be kept in the RNA area of the lab, and gloves should be worn at all times to prevent accidental contamination. Tools and equipment such as pipets, tips, and centrifuges should be designated for use only in the RNA zone as well. The location of the RNA zone in the lab is also important. Keeping traffic to a minimum and moving the RNA zone away from doors, windows, and vents can also help minimize contamination.
Using an RNase inhibitorcan also help safeguard your samples from RNase degradation. These inhibitors can bind to any RNases that may have been introduced into your sample and prevent them from cutting the RNA present.
Mapping Protein-RNA Interactions in vivo Using the HITS-CLIP Method
Aberrant RNA binding protein (RBP) function has been implicated in a host of human diseases from various cancers, neurological disorders, and conditions related to muscular atrophy (1). Understanding RBP function requires not only a working knowledge of the protein proper, but accurate methods to identify RNA binding partners in vivo. Identification of RNA binding partners has historically been difficult, especially for RNA targets involved in nervous system disorders. Methods for finding targets have involved in vitro RNA selection or co-immunoprecipitation followed by gene chip analysis (2,3). These approaches came with some inhert limitations. The signal to noise ratio is low and the ability to differentiate between direct and indirect interactions is limited. Additionally, since the RNA-protein interactions are so complex, any of the in vitro methods may not be wholly predictive of true intracellular interactions.
In 2003, researchers at the Laboratory of Molecular Neuro-Oncology at Rockefeller University developed a method to purify protein-RNA complexes from mouse brain tissue that utilized ultraviolet cross-linking of RNA to their protein binding partners and immunoprecipitation of the cross-linked product (4). Further development of the technology has resulted in a streamlined protocol to perform high-throughput sequencing of RNA isolated by crosslinking immunoprecipitation (HITS-CLIP; 5). Continue reading “Mapping Protein-RNA Interactions in vivo Using the HITS-CLIP Method”