HETEROLOGOUS EXPRESSION OF PHYTOCYANIN-LIKE ARABINOGALACTAN PROTEIN FROM DIOSCOREA ROTUNDATA AS A POTENTIAL TREATMENT TO PROMOTE SOMATIC EMBRYOGENESIS

Open Access
Author:
Shouse, Eva Mei
Area of Honors:
Chemical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Dr. Wayne Curtis, Thesis Supervisor
  • Dr. Lorraine Santy, Faculty Reader
  • Wayne Roger Curtis, Honors Advisor
Keywords:
  • endophyte
  • endosymbiont
  • PLA
  • phytocyanin-like arabinogalactan
  • Dioscorea rotundata
  • Yam
  • somatic embryogenesis
  • 16s
Abstract:
Somatic embryogenesis is the conversion of a somatic cell to a embryogenic cell, effectively creating a true clone. The Phytocyanin-like arabinogalactan (PLA) protein has been shown to enhance somatic embryogenesis of plant tissue in multiple plan species. Although the details of how PLA is involved in somatic embryogenesis are not known, its effectiveness makes the PLA protein a potential treatment to facilitate embryo formation in plant tissue culture. Furthermore, the non-glycosylated form of the protein is still functional, which opens the door for utilizing bacteria as an expression system to produce PLA protein. This thesis documents an effort to express Dioscorea rotundata PLA proteins in E. coli in order to promote somatic embryogenesis in yam tissue. Yam is an important ‘orphan crop’ of sub-Saharan Africa, where this technology will contribute to propagation systems being developed for this plant. The work starts with the identification of D. rotundata PLA genes and progressed to initial attempts at expression of DrPLA proteins in E. coli. Appendices of this thesis also describe assistance with other projects including characterization of yam culture ‘contaminants’ and likely endosymbionts as well as several other side projects.