Dr. Stephen H Howell

Charles F. Curtiss Distinguished Professor
Stephen Howell

Abiotic stresses, such as heat, drought, flooding and salt stress, are the major causes of crop losses worldwide, and, therefore, tolerance to stress is a highly valued crop trait. Stress tolerance has become an even more important trait as demands grow for producing crops for biofuels, particularly, as we face the prospects for climate change. We recently discovered a set of stress transducers located on the endoplasmic reticulum (ER) membranes in Arabidopsis that perceive and transduce several different environmental stresses. One set of stress transducers are ER membrane-associated transcription factors that are activated by proteolysis and relocated to the nucleus in response to stress. Different environmental stresses, such as heat stress and salt stress, activate different transcription factors, and we are studying the basis for that specificity. In addition, we are studying what factors are responsible for untethering the stress transducers from the ER in response to stress, how they are transported from the ER to the Golgi apparatus, how they are proteolytically processed and relocated to the nucleus and how they participate in the formation of transcription complexes to activate target genes.

Area of Expertise: 
plant stress tolerance
B.A., Grinnell College, 1963
Ph.D., Johns Hopkins University