Policies and Procedures
Acknowledgment and citing the CryoEM Core
Please acknowledge the contributions of our staff and the use of our core facility in your publications.
“We acknowledge Jared Peck and Dr. Joshua Strauss of the UNC CryoEM Core Facility for technical assistance in this project”
“Data was collected at the UNC at Chapel Hill CryoEM Core Facility with a 200 kV Thermo Fisher Scientific Talos Arctica G3 equipped with a Gatan K3 direct electron detector”.
We offer fee-for-services for (1) cryo-grid sample preparation using a Vitrobot Mark IV, (2) Screening and Data collection using Talos Artica CryoTEM. Booking equipment and billing are done in iLAB, make sure to have an account set up before using the CryoEM Core. If you would like to learn how to operate the Vitrobot and Talos Artica please contact the Core Directory directly and request training.
We do not offer image processing of cryoEM data or building atomic models from EM maps as a fee-for-service. Pre-processing of single-particle cryoEM data including motion correction and CTF estimation using CryoSPARC Live is not considered “image processing” and included in the data collection. Anything beyond this (motion correction and CTF estimation) is considered image processing. Having the ability to process data on the fly is incredibly useful. We routinely will generate 2D class averages and 3D models, to determine the structure of the target complex as it is being collected. If you need assistance with this we are happy to help, we only ask that you acknowledge the CryoEM Core Staff that process the data. This can be done during data collection and typically takes a few hours to complete. Anything beyond this is considered extra, and the Core Staff that are processing the data are considered collaborators and authors.
Operation of the Vitrobot
Only trained users are permitted to operate the Vitrobot. The Vitrobot is located in Glaxo Research Building room 011 across the hall from the Talos Arctica. The Vitrobot Mark VI can be reserved using iLAB. If you need assistance or require training please contact us directly.
Operation of the Talos Arctica
The Talos Arctica is used for mainly specimen screening and also high-resolution data collection. Only trained users are permitted to operate the Talos Arctica. Researchers interested in getting trained or using the microscope please contact the cryoEM core director Dr. Joshua Strauss. Only cryoEM core staff are allowed to dock/undock the Cassettes into the Autoloader and load Cartridges into the Cassette. We limit the number of docking/undockings to two per day and only during working hours of the core 9AM-7PM. We are now doing (two Cassette exchanges) shifts each day M-F. The morning session 9AM-2PM is only for screening samples with the option to collect a small data set of 100- 300 movies. The evening session from 2PM-8PM is for either (1) screening samples with the option to collect a data set overnight, or (2) for collecting data overnight. Data can be collected over the weekends, typically we will load the sample Friday and monitor data collection remotely.
Each core user is responsible for the long-term storage of their data. Data collected from the Gatan K3 camera are stored in the Dogwood/Longleaf shared file drive where it can be accessed via Globus. We do not offer long-term storage (> 3 mounts) for data collected with the Talos Arctica TEM. Additional information about the Dogwood and Longlecomputerers clusters are on the UNC Research Computing website https://its.unc.edu/research-computing/techdocs/longleaf-frequently-asked-questions-faqs/
Storage of Cryogrids
Core users can store cryo-grids in the Biocain34 liquid nitrogen dewar located in the cryo-prep room at Glaxo Research building. The cryoEM core maintains a record of the samples stored in this dewar, however, we encourage people to keep a duplicate record of the location of their samples. Only cryoEM core staff are permitted to remove and place samples in the Biocain34 dewar. Each lab is allowed one puck to store their cryo-grids. If you need more than one puck contact the Core Director.