Abstract/Details

The roles of signal peptide peptidase -like proteases in Arabidopsis thaliana


2008 2008

Other formats: Order a copy

Abstract (summary)

The signal peptide peptidases (SPP) are a class of intramembrane cleaving proteases (I-CLiPs) that share very conserved aspartate (GxGD) and PxL domains (QPALLY motif in SPPL) in all eukaryotes. In addition to a role in the disposal of cleaved signal peptides from secretory proteins, human SPP has been proposed to play an important role in viral assembly, ER quality control, immune surveillance and cellular signaling. I have used the facile genetic system of the model plant species, Arabidopsis thaliana, to investigate the roles of the SPP family in plants and gain insight into their roles in other eukaryotic systems. Arabidopsis contains six SPP-like genes. I focused the initial studies on AtSPP (AGI:At2g03120), the protein most similar to human SPP. Like human SPP, AtSPP is an ER resident protein. A T-DNA insertion mutant of the AtSPP gene, spp-2, exhibits a fertility defect that can be traced to a block in pollen germination. The distribution of the male germ unit (MGU) in mature pollen was severely affected in +/spp-2 plants. In addition, AtSPP RNAi lines exhibited sucrose dependency in seed germination and reduced root growth in seedlings. Studies with the proherbicide, 2,4-dichlorophenoxybutric acid, indicated that AtSPP RNAi lines were defective in beta-oxidation. Based upon the results, I conclude that AtSPP is an ER localized protease that is essential for pollen development and vegetative growth due to a role in regulating lipid metabolism.

Indexing (details)


Subject
Molecular biology;
Biochemistry;
Plant biology
Classification
0307: Molecular biology
0487: Biochemistry
0817: Plant biology
Identifier / keyword
Pure sciences, Biological sciences, Arabidopsis, Peptidase-like proteases, Signal peptide peptidase
Title
The roles of signal peptide peptidase -like proteases in Arabidopsis thaliana
Author
Han, Sungwon
Number of pages
104
Publication year
2008
Degree date
2008
School code
0118
Source
DAI-B 69/12, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
ISBN
9780549915973
Advisor
Schnell, Danny J.
Committee member
Baskin, Tobias; Hebert, Daniel; Walker, Elsbeth
University/institution
University of Massachusetts Amherst
Department
Molecular & Cellular Biology
University location
United States -- Massachusetts
Degree
Ph.D.
Source type
Dissertations & Theses
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
3337010
ProQuest document ID
304566927
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
http://search.proquest.com/docview/304566927
Access the complete full text

You can get the full text of this document if it is part of your institution's ProQuest subscription.

Try one of the following:

  • Connect to ProQuest through your library network and search for the document from there.
  • Request the document from your library.
  • Go to the ProQuest login page and enter a ProQuest or My Research username / password.