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1b3u
From Proteopedia
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| , resolution 2.3Å | |||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF CONSTANT REGULATORY DOMAIN OF HUMAN PP2A, PR65ALPHA
Overview
The PR65/A subunit of protein phosphatase 2A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit, generating functionally diverse heterotrimers. Mutations of the beta isoform of PR65 are associated with lung and colon tumors. The crystal structure of the PR65/Aalpha subunit, at 2.3 A resolution, reveals the conformation of its 15 tandemly repeated HEAT sequences, degenerate motifs of approximately 39 amino acids present in a variety of proteins, including huntingtin and importin beta. Individual motifs are composed of a pair of antiparallel alpha helices that assemble in a mainly linear, repetitive fashion to form an elongated molecule characterized by a double layer of alpha helices. Left-handed rotations at three interrepeat interfaces generate a novel left-hand superhelical conformation. The protein interaction interface is formed from the intrarepeat turns that are aligned to form a continuous ridge.
About this Structure
1B3U is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
The structure of the protein phosphatase 2A PR65/A subunit reveals the conformation of its 15 tandemly repeated HEAT motifs., Groves MR, Hanlon N, Turowski P, Hemmings BA, Barford D, Cell. 1999 Jan 8;96(1):99-110. PMID:9989501
Page seeded by OCA on Sun Mar 30 18:53:00 2008
