creator Yang, Jingyi advisor Pombert, Jean-Fran�ois Pedicularis rex is a hemiparasitic plant from the Orobanchaceae family. Hemiparasites, also called semiparasites, are partly dependent on their host and, while they steal nutrients and other metabolites like other parasites, they have retained their photosynthesis ability. To better understand the hemiparasitic lifestyle of Pedicularis rex and what remains of its photosynthetic capability, we have determined the complete sequence of its plastid chromosome. The chloroplast genome of Pedicularis rex is 153,650 base pairs-long and exhibits a typical quadripartite structure with a large single copy (LSC) region and a small single copy (SSC) region separated by two inverted repeats (IR). A total of 79 unique protein-coding genes, including 9 pseudogenes, 30 tRNA- and 4 rRNA-encoding genes were retained in the plastid genome. Compared to the plastome of its close non-parasitic relative Lindenbergia philippensis, only one protein-coding gene and one intron are missing from P. rex but many genes show signs of pseudogenization. Pseudogenization in the P. rex plastid genome was found to be mainly caused by single site insertions, deletions or substitutions. The overall high level of homology between the P. rex and L. philippensis plastomes may explain why P. rex shows weak host dependence. However, how P. rex maintains its photosynthetic capability despite featuring a number of potentially dysfunctional pseudogenes involved in photosynthesis is unclear, and the minimal set of genes that is required for hemiparasitic plants to keep their autotrophic lifestyle is still unknown. Submitted by Erma Thomas (thomase@iit.edu) on 2016-02-18T22:58:07Z No. of bitstreams: 1 etdadmin_upload_373825.zip: 1386174 bytes, checksum: c0e999cfa36e19ec9d2186132e2850f9 (MD5) Made available in DSpace on 2016-02-18T22:58:07Z (GMT). No. of bitstreams: 1 etdadmin_upload_373825.zip: 1386174 bytes, checksum: c0e999cfa36e19ec9d2186132e2850f9 (MD5) Previous issue date: 2015-07 M.S. in Biology, July 2015 2015 2015-07 http://hdl.handle.net/10560/3721 en gene loss hemiparasite Pedicularis plastid genome Thesis born digital application/pdf In Copyright http://rightsstatements.org/page/InC/1.0/ Restricted Access BIOL / Biology Illinois Institute of Technology Affiliated department