Molecular cloning of a protein serine/threonine phosphatase containing a putative regulatory tetratricopeptide repeat domain

Two novel protein serine/threonine phosphatases were cloned from a rat fat cell library with probes generated by a polymerase chain reaction-based cloning approach. One of these cDNAs encoded a protein presumably representing the rat homologue of PPV from Drosophila (75% identity of amino acids). Th...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of biological chemistry 1994-09, Vol.269 (36), p.22586-22592
Main Authors: Becker, W, Kentrup, H, Klumpp, S, Schultz, J E, Joost, H G
Format: Article
Language:English
Subjects:
3T3 Cells
Amino Acid Sequence
Animals
Base Sequence
Cloning, Molecular
DNA Primers
Drosophila - enzymology
Escherichia coli
Gene Expression
Male
Mice
Molecular Sequence Data
Multigene Family
Phosphoprotein Phosphatases - biosynthesis
Phosphoprotein Phosphatases - chemistry
Phosphoprotein Phosphatases - genetics
Phylogeny
Polymerase Chain Reaction
Protein Phosphatase 1
Rabbits
Rats
Regulatory Sequences, Nucleic Acid
Repetitive Sequences, Nucleic Acid
Sequence Homology, Amino Acid
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Two novel protein serine/threonine phosphatases were cloned from a rat fat cell library with probes generated by a polymerase chain reaction-based cloning approach. One of these cDNAs encoded a protein presumably representing the rat homologue of PPV from Drosophila (75% identity of amino acids). The other novel cDNA encoded a protein phosphatase of 499 amino acids and was designated PPT. Its catalytic domain contains motifs typical for protein phosphatases but is only distantly related with PP1, PP2A, and PP2B (38-42% identical amino acids). When expressed in Escherichia coli, the catalytic domain of PPT exhibited protein phosphatase activity (dephosphorylation of phosphorylase a) that was inhibitable by okadaic acid. As a unique feature among other members of this gene family, PPT has an amino-terminal extension of 200 amino acids harboring three tandemly arranged tetratricopeptide repeat (TPR) motifs. This domain has previously been found in other proteins involved in the regulation of RNA synthesis or mitosis. mRNA of PPT was predominantly found in brain and, in lower levels, in testis, but was nearly undetectable in spleen, lung, skeletal muscle, kidney, and liver. It is suggested that the TPR domain of PPT may be involved in the regulation of the function of this novel protein phosphatase.
ISSN:0021-9258
1083-351X
DOI:10.1016/s0021-9258(17)31686-1