Boston venture capital firm Third Rock Ventures is unveiling a new company that analyzes the movement of proteins inside human cells, potentially giving researchers a fuller picture of the best targets for new drugs.

Relay Therapeutics Inc., based in Cambridge, said Tuesday it has raised $57 million from Third Rock and D.E. Shaw Research, a New York-based biochemistry research company. Relay, which has been operating quietly for about six months, plans to grow from about 25 employees to 40 in the next year, chief executive Alexis Borisy said.

The approach is typical of Third Rock, which seeks to incubate biotech startups and launch them into the market rather than hunting for already established companies to stake with investment cash.

Borisy said Relay blends several techniques to create digital movies of the proteins inside cells, which perform specialized functions that keep the microscopic machinery of life functioning.

Those proteins may detect changes in the cell’s environment, relay messages on to other cellular structures, or produce immune responses that can attack biological invaders. Drug developers are keenly interested in studying these cellular proteins because they can reveal “targets’’ that drug molecules can latch onto, potentially changing how a cell operates.

But typical analysis techniques, Borisy said, only give researchers static images of how these proteins operate within the body. Giving researchers a moving picture, on the other hand, allows drug developers to see whether a particular drug target is still viable after a protein changes shape or shifts positions, he said.

“There’s the old saying, a picture is worth a thousand words,’’ Borisy said. “Here, we’re saying a movie is worth thousands and thousands of pictures.’’

Borisy said Relay can create those movies by combining imaging technologies, such as X-ray and magnetic resonance, with powerful data analysis software that can re-create the ways certain proteins move over long periods of time.

“It’s a philosophical shift in how you think about doing drug discovery,’’ he said.

Relay plans to target its own drug-candidate research on cancers. But the startup also may collaborate with other companies to use its technology in neuroscience and immunology research, Borisy said.

Curt Woodward can be reached at curt.woodward@globe.com. Follow him on Twitter @curtwoodward.