Limits...
PERK-KIPK-KCBP signalling negatively regulates root growth in Arabidopsis thaliana.

Humphrey TV, Haasen KE, Aldea-Brydges MG, Sun H, Zayed Y, Indriolo E, Goring DR - J. Exp. Bot. (2014)

Bottom Line: In this study, we focused on the characterization of a subclade of three Arabidopsis predicted PERK genes, PERK8, -9, and -10, for which no functions were known.Yeast two-hybrid interaction studies were conducted with the PERK8,- 9, and -10 cytosolic kinase domains, and two members of the Arabidopsis AGC VIII kinase family were identified as interacting proteins: AGC1-9 and the closely related kinesin-like calmodulin-binding protein (KCBP)-interacting protein kinase (KIPK).As KIPK has been identified previously as an interactor of KCBP, these interactions were also examined further and confirmed in this study.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell & Systems Biology, University of Toronto, Toronto, Canada M5S 3B2.

No MeSH data available.


T-DNA insertion sites for the PERK, KIPK, and KCBP genes. On the left, schematics display the Arabidopsis SALK T-DNA insertion lines for the PERK8, PERK9, PERK10, KIPK1, and KCBP genes (Alonso et al., 2003) and the GABI-Kat T-DNA insertion line for KIPK2 (Rosso et al., 2003). On the right, RT-PCR analyses using gene-specific primers show the loss of gene-specific transcripts in each homozygous mutant, indicating that each T-DNA insertion is a knockout line. Actin primers were used as positive controls for each sample. T-DNA insertion sites were obtained from the SIGnAL website (http://signal.salk.edu), and gene models were obtained from The Arabidopsis Information Resource on 1 June, 2011 (http://www.arabidopsis.org) (Rhee et al., 2003).
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4265151&req=5

Figure 3: T-DNA insertion sites for the PERK, KIPK, and KCBP genes. On the left, schematics display the Arabidopsis SALK T-DNA insertion lines for the PERK8, PERK9, PERK10, KIPK1, and KCBP genes (Alonso et al., 2003) and the GABI-Kat T-DNA insertion line for KIPK2 (Rosso et al., 2003). On the right, RT-PCR analyses using gene-specific primers show the loss of gene-specific transcripts in each homozygous mutant, indicating that each T-DNA insertion is a knockout line. Actin primers were used as positive controls for each sample. T-DNA insertion sites were obtained from the SIGnAL website (http://signal.salk.edu), and gene models were obtained from The Arabidopsis Information Resource on 1 June, 2011 (http://www.arabidopsis.org) (Rhee et al., 2003).

Mentions: KCBP is the only gene in the PERK(8,9,10)–KIPK(1,2)–KCBP set with a known function in Arabidopsis; that is, in trichome morphogenesis. The zwichel (zwi) mutant, identified in a screen for trichome mutants, was determined to be a loss-of-function kcbp mutant and displayed defects in trichome cell expansion resulting in shorter stalks and reduced branching (Oppenheimer et al., 1997). To search for overlapping in planta functions for the PERK(8,9,10)–KIPK(1,2)–KCBP set, loss-of-function homozygous T-DNA mutants were identified for all six genes (Fig. 3). The mutants were also crossed to form multiple gene knockout mutants and screened for altered phenotypes. As expected, kcbp-1 displayed the reduced trichome branching phenotype reported previously for the zwi/kcbp mutant (Oppenheimer et al., 1997). Any mutant combinations with kcbp-1 also showed the reduced trichome branching: the perk8-1,9-1,10-1,kcbp-1 quadruple mutant and kipk1-1,2-1,kcbp-1 triple mutant (Supplementary Fig. S2 at JXB online.). However, the trichomes were normal in appearance for the perk8-1,9-1,10-1 triple mutant and the kipk1-1,2-1 double mutant (Supplementary Fig. S2), suggesting that these proteins did not participate in the regulation of KCBP during trichome formation. In addition, plants from all these mutant combinations did not display any detectable growth or floral defects when grown on soil (Supplementary Fig. S2).


PERK-KIPK-KCBP signalling negatively regulates root growth in Arabidopsis thaliana.

Humphrey TV, Haasen KE, Aldea-Brydges MG, Sun H, Zayed Y, Indriolo E, Goring DR - J. Exp. Bot. (2014)

T-DNA insertion sites for the PERK, KIPK, and KCBP genes. On the left, schematics display the Arabidopsis SALK T-DNA insertion lines for the PERK8, PERK9, PERK10, KIPK1, and KCBP genes (Alonso et al., 2003) and the GABI-Kat T-DNA insertion line for KIPK2 (Rosso et al., 2003). On the right, RT-PCR analyses using gene-specific primers show the loss of gene-specific transcripts in each homozygous mutant, indicating that each T-DNA insertion is a knockout line. Actin primers were used as positive controls for each sample. T-DNA insertion sites were obtained from the SIGnAL website (http://signal.salk.edu), and gene models were obtained from The Arabidopsis Information Resource on 1 June, 2011 (http://www.arabidopsis.org) (Rhee et al., 2003).
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4265151&req=5

Figure 3: T-DNA insertion sites for the PERK, KIPK, and KCBP genes. On the left, schematics display the Arabidopsis SALK T-DNA insertion lines for the PERK8, PERK9, PERK10, KIPK1, and KCBP genes (Alonso et al., 2003) and the GABI-Kat T-DNA insertion line for KIPK2 (Rosso et al., 2003). On the right, RT-PCR analyses using gene-specific primers show the loss of gene-specific transcripts in each homozygous mutant, indicating that each T-DNA insertion is a knockout line. Actin primers were used as positive controls for each sample. T-DNA insertion sites were obtained from the SIGnAL website (http://signal.salk.edu), and gene models were obtained from The Arabidopsis Information Resource on 1 June, 2011 (http://www.arabidopsis.org) (Rhee et al., 2003).
Mentions: KCBP is the only gene in the PERK(8,9,10)–KIPK(1,2)–KCBP set with a known function in Arabidopsis; that is, in trichome morphogenesis. The zwichel (zwi) mutant, identified in a screen for trichome mutants, was determined to be a loss-of-function kcbp mutant and displayed defects in trichome cell expansion resulting in shorter stalks and reduced branching (Oppenheimer et al., 1997). To search for overlapping in planta functions for the PERK(8,9,10)–KIPK(1,2)–KCBP set, loss-of-function homozygous T-DNA mutants were identified for all six genes (Fig. 3). The mutants were also crossed to form multiple gene knockout mutants and screened for altered phenotypes. As expected, kcbp-1 displayed the reduced trichome branching phenotype reported previously for the zwi/kcbp mutant (Oppenheimer et al., 1997). Any mutant combinations with kcbp-1 also showed the reduced trichome branching: the perk8-1,9-1,10-1,kcbp-1 quadruple mutant and kipk1-1,2-1,kcbp-1 triple mutant (Supplementary Fig. S2 at JXB online.). However, the trichomes were normal in appearance for the perk8-1,9-1,10-1 triple mutant and the kipk1-1,2-1 double mutant (Supplementary Fig. S2), suggesting that these proteins did not participate in the regulation of KCBP during trichome formation. In addition, plants from all these mutant combinations did not display any detectable growth or floral defects when grown on soil (Supplementary Fig. S2).

Bottom Line: In this study, we focused on the characterization of a subclade of three Arabidopsis predicted PERK genes, PERK8, -9, and -10, for which no functions were known.Yeast two-hybrid interaction studies were conducted with the PERK8,- 9, and -10 cytosolic kinase domains, and two members of the Arabidopsis AGC VIII kinase family were identified as interacting proteins: AGC1-9 and the closely related kinesin-like calmodulin-binding protein (KCBP)-interacting protein kinase (KIPK).As KIPK has been identified previously as an interactor of KCBP, these interactions were also examined further and confirmed in this study.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell & Systems Biology, University of Toronto, Toronto, Canada M5S 3B2.

No MeSH data available.