Samuel De Riseis

The Role of the Sorghum Circadian Clock in Blue Light-Mediated Growth

Sorghum bicolor is a biofuel feedstock and staple food crop. My research focuses on understanding the role of a core circadian clock component, Sorghum bicolor Gigantea (SbGI), in modulating sorghum sensitivity to cryptochrome signaling at different times of the day. In related grasses, cryptochromes, activated by blue light, upregulate active gibberellin degradation genes to strategically cease plant elongation. Importantly, the SbGI mutant has a severe stunted-growth phenotype relative to the wild type, and preliminary protein interaction results suggest that SbGI and cryptochromes interact. These observations inform my hypothesis that SbGI is necessary for blocking cryptochrome activity to allow for active gibberellin to accumulate in a time-specific manner to drive diurnal growth. The confirmation of this mechanism would be the first documentation of a Gigantea-cryptochrome interaction and would inform us about how the circadian clock directly coordinates daily growth. If it is known when, under what conditions, and how growth is occurring, agricultural inputs can be precisely added to favor when crops can most efficiently uptake and use these resources.

Message to Sponsor

Thank you for generously funding my research! This provides me the autonomy to focus solely on research; a rarity as an undergraduate. I'm looking forward to gaining valuable insights into the research world that I wouldn't be exposed to without this fellowship. I really appreciate the opportunity!
  • Major: Microbial Biology
  • Sponsor: Rose Hills Foundation
  • Mentor: Frank Harmon