Protein tyrosine phosphatase zeta/RPTPbeta interacts with PSD-95/SAP90 family.
PTPzeta/RPTPbeta is a proteoglycan-type receptor-like protein tyrosine phosphatase specifically expressed in the brain. Although several ligands of PTPzeta have been identified, proteins interacting with the intracellular region of PTPzeta are still unknown. We performed yeast two-hybrid screening using the intracellular region of PTPzeta as a bait, and found that the C-terminal sequence of PTPzeta binds to the PSD-95/SAP90 family through the second PDZ domain. Immunohistochemical analysis revealed that PTPzeta and PSD-95/SAP90 are similarly distributed in the dendrites of pyramidal neurons of the hippocampus and neocortex. Furthermore, subcellular fractionation experiments indicated that PTPzeta is concentrated in the postsynaptic density fraction. These results suggested that PTPzeta is involved in the regulation of synaptic function as postsynaptic macromolecular complexes with PSD-95/SAP90.
Kawachi
H
H
Division of Molecular Neurobiology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji-cho, Okazaki, Japan.
Tamura
H
H
Watakabe
I
I
Shintani
T
T
Maeda
N
N
Noda
M
M
D000818:Animals; D000076122:Disks Large Homolog 4 Protein; D006624:Hippocampus / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D019579:Neocortex / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D017027:Protein Tyrosine Phosphatases / Q000737:chemistry / Q000378:metabolism*; D017966:Pyramidal Cells / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D054633:Receptor-Like Protein Tyrosine Phosphatases, Class 5; D000074407:SAP90-PSD95 Associated Proteins; D013347:Subcellular Fractions / Q000378:metabolism; D009435:Synaptic Transmission; D020798:Two-Hybrid System Techniques
D000076122:Disks Large Homolog 4 Protein; C501449:Dlg4 protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D000074407:SAP90-PSD95 Associated Proteins; C033652:postsynaptic density proteins; D017027:Protein Tyrosine Phosphatases; C516852:Ptprg protein, rat; D054633:Receptor-Like Protein Tyrosine Phosphatases, Class 5