---
pmid: '17174897'
title: Structure of the protein phosphatase 2A holoenzyme.
authors:
- Xu Y
- Xing Y
- Chen Y
- Chao Y
- Lin Z
- Fan E
- Yu JW
- Strack S
- Jeffrey PD
- Shi Y
journal: Cell
year: '2006'
full_text_available: false
doi: 10.1016/j.cell.2006.11.033
---

# Structure of the protein phosphatase 2A holoenzyme.
**Authors:** Xu Y, Xing Y, Chen Y, Chao Y, Lin Z, Fan E, Yu JW, Strack S, Jeffrey PD, Shi Y
**Journal:** Cell (2006)
**DOI:** [10.1016/j.cell.2006.11.033](https://doi.org/10.1016/j.cell.2006.11.033)

## Abstract

1. Cell. 2006 Dec 15;127(6):1239-51. doi: 10.1016/j.cell.2006.11.033.

Structure of the protein phosphatase 2A holoenzyme.

Xu Y(1), Xing Y, Chen Y, Chao Y, Lin Z, Fan E, Yu JW, Strack S, Jeffrey PD, Shi 
Y.

Author information:
(1)Department of Molecular Biology, Lewis Thomas Laboratory, Princeton 
University, Princeton, NJ 08544, USA.

Protein Phosphatase 2A (PP2A) plays an essential role in many aspects of 
cellular physiology. The PP2A holoenzyme consists of a heterodimeric core 
enzyme, which comprises a scaffolding subunit and a catalytic subunit, and a 
variable regulatory subunit. Here we report the crystal structure of the 
heterotrimeric PP2A holoenzyme involving the regulatory subunit B'/B56/PR61. 
Surprisingly, the B'/PR61 subunit has a HEAT-like (huntingtin-elongation-A 
subunit-TOR-like) repeat structure, similar to that of the scaffolding subunit. 
The regulatory B'/B56/PR61 subunit simultaneously interacts with the catalytic 
subunit as well as the conserved ridge of the scaffolding subunit. The 
carboxyterminus of the catalytic subunit recognizes a surface groove at the 
interface between the B'/B56/PR61 subunit and the scaffolding subunit. Compared 
to the scaffolding subunit in the PP2A core enzyme, formation of the holoenzyme 
forces the scaffolding subunit to undergo pronounced conformational 
rearrangements. This structure reveals significant ramifications for 
understanding the function and regulation of PP2A.

DOI: 10.1016/j.cell.2006.11.033
PMID: 17174897 [Indexed for MEDLINE]