Student Research Projects

Transformation of Physcomitrella patens with three DNA constructs, to assess the function of a Fasciclin-like Arabinogalactan Protein

Student Lemar Callaway III, '18
Faculty Mentor(s)
Department Biology
Course BIO 489: Undergraduate Research


Arabinogalactan proteins (AGP) are a class of glycosylated protein commonly found in plants. These highly conserved proteins have been implicated in various cellular processes, including cell growth and proliferation, and microbial interactions (Seifert and Roberts 137). The model moss, Physcomitrella patens is amenable to homologous recombination allowing for specific gene targeting within the genome. This together with its membership in one of the oldest plant lineages of land plants makes it an important tool in assessing plant molecular evolution. We are probing the importance of these proteins in reproductive development, for which AGPs have been shown to play a role in many lineages by an unknown mechanism. We have previously identified a Fasciclin-like AGP as being upregulated in plants with developing sperm cells. The goal of this project was to develop three transgenic lines such that we could assess the spatial expression pattern of the AGP22-encoding gene and determine if sperm cell development is altered in AGP22-knockout plants. Through multiple attempts and troubleshooting, we were able to successfully transform two of the three constructs into P. patens. One of the two constructs was a gene coding for a hybrid Gus linked AGP22 protein and the other construct was a gene encoding for a hybrid Gus linked ubiquitin protein. Future projects will address the analysis of the phenotypes of these two transformed P. patens lines, as well as attempt to successfully transform an AGP22 knockout line for P. patens.