Magnetic resonance imaging (MRI) has shown anatomy and structure for decades but usually cannot report molecular activity inside cells. Researchers at the University of California, Santa Barbara built a genetically encoded, protein-based sensor that an MRI can detect inside living cells.
The sensor uses aquaporin, a protein channel for water, and combines it with other proteins to form interchangeable genetic circuits. The team applied synthetic biology ideas to make the system modular so parts can be swapped to sense different processes. A PhD student helped tune the system so it responds to chemical signals.
The paper reports that the setup can detect nearly ten different systems, whereas earlier studies showed only four or five genetic sensors. The researchers expect MAPPER to allow continuous imaging in animal studies and to reduce the need to sacrifice animals for internal measurements.
Difficult words
- encode — to store instructions in genes or DNAencoded
- aquaporin — a protein channel for water in cells
- modular — made of parts that can be changed
- synthetic biology — science that engineers living cells and systems
- interchangeable — able to be exchanged or used in place
- tune — to adjust or change to get better response
- sacrifice — to end animals' lives for research use
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- How could continuous imaging reduce the need to sacrifice animals in studies?
- What advantages do sensors that MRI can detect inside living cells offer to researchers?
- Would you feel comfortable with genetically encoded sensors used in animal research? Why or why not?
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