Item – Theses Canada

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OCLC number
653384321
Link(s) to full text
LAC copy
LAC copy
Author
Baxter, Joyce.
Title
Identification of a functionally essential amino acid for an Arabidopsis cyclic nucleotide-gated ion channel.
Degree
M. Sc. -- University of Toronto, 2007
Publisher
Ottawa : Library and Archives Canada = Bibliothèque et Archives Canada, [2009]
Description
2 microfiches
Notes
Includes bibliographical references.
Abstract
The 'cpr22 Arabidopsis' mutant shows constitutive activation of pathogen resistance responses and has spontaneous lesions. ' cpr22' was identified to encode for a novel chimeric gene, ' ATCNGC11/12', created by a fusion between 'ATCNGC11' and '12'. Previous analyses suggested that 'ATCNGC 11/12 ' forms a functional cAMP-activated CNGC in yeast and that the phenotype conferred by 'cpr22' is attributable to the expression Of ' ATCNGC11/12'. To identify downstream components of the 'cpr22 '-mediated signal transduction pathway or identify functionally important residues of this channel, a genetic screen for mutants that suppress ' cpr22'-related phenotypes was conducted. One suppressor, 7 3 was identified to have an intragenic mutation in 'ATCNGC11/12'. In this project, I have characterized the 7 3 mutant and analyzed the mechanism to suppress the 'cpr22' phenotypes by this mutation. This mutation, E519K, is located in the cyclic nucleotide binding domain. Our computational modeling suggests that this mutation alters an important amino acid necessary for channel activity and intra/inter subunit interactions that stabilize the tertiary channel structure.
ISBN
9780494401002
0494401001