FRONTIER BIOLOGY, 2013, 8 (5)
RasGRP Ras guanine nucleotide exchange factors in cancer
Olga KSIONDA, Andre LIMNANDER, Jeroen P. ROOSE
Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
Abstract RasGRP proteins are activators of Ras and other related small GTPases by the virtue of functioning as guanine nucleotide exchange factors (GEFs). In vertebrates, four RasGRP family members have been described. RasGRP-1 through -4 share many structural domains but there are also subtle differences between each of the different family members. Whereas SOS RasGEFs are ubiquitously expressed, RasGRP proteins are expressed in distinct patterns, such as in different cells of the hematopoietic system and in the brain.