Mitochondria (image) Penn State Share Print E-Mail Caption Researchers discovered that proteins, represented by the black line, exert a mechanical force as they exit the molecular machine where they are synthesized, represented in red. That force moderates the speed of protein synthesis. Credit Benjamin Fritch Usage Restrictions Non comercial use only Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.