Biochemical Characterization of SBIP-470 and its role in SA-mediated Signaling in Plants

• Main Author: Chapagai, Danda P
• Format: Others
• Published: Digital Commons @ East Tennessee State University 2014
• Subjects: Plant Defense; Salicylic Acid; Systemic Acquired Resistance; Salicylic Acid Binding Protein 2; Lipid Transfer Protein; Lipid binding; Biology
• Online Access: https://dc.etsu.edu/etd/2428; https://dc.etsu.edu/cgi/viewcontent.cgi?article=3792&context=etd

Salicylic acid binding protein 2 (SABP2) is known to play a key role in Salicylic acid mediated defense pathway. SBIP-470 is SABP2 interacting protein that might be putatively involved in transfer of lipids. SBIP-470 was cloned without the signal peptide and expressed in E. coli. In vitro lipid binding assay using recombinant SBIP-470 failed to detect lipid binding. In vitro lipid transfer assay showed recombinant SBIP-470 does not transfer phospholipid. Study has shown that SBIP-470 is highly inducible upon infection with viral as well as bacterial pathogens. Induction of SBIP-470 expression upon the TMV infection most likely depends upon the SABP2 while its expression upon non-host bacterial pathogens is most probably inhibited by the SABP2. A study of Arabidopsis knockout mutants (ltp12 mutant and ltp2 mutant) lacking the SBIP-470 homolog genes showed defects in growth phenotype, and they were found susceptible to bacterial pathogens.