Graduate Program

Biological Sciences

Degree Name

Master of Science (MS)

Semester of Degree Completion

Spring 2022

Thesis Director

Yordan S. Yordanov

Thesis Committee Member

Gary A. Bulla

Thesis Committee Member

Thomas Canam


Tissue-specific promoters are a valuable tool in plant biotechnology because they allow for precise spatial control of transgene expression. To identify root-specific promoters in sunflower (Helianthus annuus), sunflower RNA sequence (RNA-seq) data were screened in silico by Pavlidis Template Matching (PTM) with a root-specific template. Eight root-specific genes were identified in sunflower. The 2.5kbp promoter regions of six of these root-specific sunflower genes (HaTOR1L3, HaGOXL3A, HaGOXL3B, HaAPA1, HaPOE1, and HaMOP10) were successfully cloned as well as the 3kbp promoter regions of four root-specific genes previously identified in poplar (Populus trichocarpa) (PtWRKY72, PtAGL16, PtMYB36, and PtAHL20). These promoters were fused with the GUSPlus β-glucuronidase reporter system in the pORE plasmid. These constructs were used to produce transgenic tobacco (Nicotiana tabacum) using Agrobacterium tumefaciens-mediated leaf disk transformation. GUS staining of these transgenic plants revealed GUS expression to be predominantly in roots for the HaAPA1, HaPOE1, HaMOP10, PtWRKY72, PtMYB36, and PtAHL20 constructs.