Blakeslee, Joshua , Zhou, H.W. , Heath, J.T. , DeLong, A. .
Subcellular Localization of Regulatory A Subunits of Arabidopsis Protein Phosphatase 2A.
Protein phosphatases play crucial roles in the regulation of plant growth and development. In particular, the serine/threonine protein phosphatase 2A (PP2A) acts in several pathways of agricultural significance, including root growth, stem elongation, and pollination. PP2A normally functions as a heterotrimeric holoenzyme complex consisting of a catalytic C subunit and regulatory B and A subunits, with the A subunit providing a scaffold for the complex. Some insight into PP2A function in plants has been gained from characterization of the regulatory A subunits (RCN1, PP2AA2 and PP2AA3) of Arabidopsis PP2A. RCN1 functions in multiple processes, including auxin transport, ethylene biosynthesis/response, ABA response, reproductive development and embryogenesis, indicating important roles for RCN1 in regulating hormone signaling and developmental pathways. Previous studies have shown that rcn1 mutant phenotypes are due to reduced PP2A activity and reflect biological specificity in A regulatory subunit function. RCN1-YFP fusion proteins that complement rcn1 phenotypes exhibit ubiquitous subcellular localization patterns in seedlings. In addition to confirming an abundant soluble population of A subunits, cell fractionation experiments have revealed that native RCN1, PP2AA3, and PP2AA3 are stably associated with microsomal membranes. We are determining whether RCN1 plays an equivalent regulatory role on PP2A activity in both soluble and membrane-associated fractions. The subcellular localization and regulatory roles of PP2AA2 and PP2AA3 in soluble vs. membrane-associated fractions are also being investigated.
Log in to add this item to your schedule
1 - Brown University, Department of Molecular Biology, Cellular Biology, and Biochemistry, Box G-L137 Sydney Frank Hall of Life Sciences, 60 Olive Street, Providence, RI, 02912, USA
2 - Caritas Christi Hospital, Neurobiology
3 - Brown University, Molecular Biology, Cellular Biology, and Biochemistry
Protein Phosphatase 2A
Presentation Type: Plant Biology Abstract
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM