A Way by which Plants Assess the Quality of Shade (image) Salk Institute Share Print E-Mail Caption Salk scientists find a previously unknown growth pathway that lets plants avoid shade. Yellow signal is emitted when a blue light receptor protein, called cryptochrome 2 (CRY2) interacts with a transcription factor PIF4, in the nucleus, regulating genes to begin a growth cycle and avoid the shade. Credit Salk Institute Usage Restrictions with associated coverage and credit 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.