Journal article
Brain Actin-associated Protein Phosphatase 1 Holoenzymes Containing Spinophilin, Neurabin, and Selected Catalytic Subunit Isoforms
The Journal of biological chemistry, Vol.274(50), pp.35845-35854
12/10/1999
DOI: 10.1074/jbc.274.50.35845
PMID: 10585469
Abstract
We previously characterized PP1bp134 and PP1bp175, two neuronal proteins that bind the protein phosphatase 1 catalytic subunit (PP1). Here we purify from rat brain actin-cytoskeletal extracts PP1(A) holoenzymes selectively enriched in PP1gamma(1) over PP1beta isoforms and also containing PP1bp134 and PP1bp175. PP1bp134 and PP1bp175 were identified as the synapse-localized F-actin-binding proteins spinophilin (Allen, P. B., Ouimet, C. C., and Greengard, P. (1997) Proc. Natl. Acad. Sci. U. S. A. 94, 9956-9561; Satoh, A., Nakanishi, H., Obaishi, H., Wada, M., Takahashi, K., Satoh, K., Hirao, K., Nishioka, H., Hata, Y., Mizoguchi, A., and Takai, Y. (1998) J. Biol. Chem. 273, 3470-3475) and neurabin (Nakanishi, H., Obaishi, H., Satoh, A., Wada, M., Mandai, K., Satoh, K., Nishioka, H. , Matsuura, Y., Mizoguchi, A., and Takai, Y. (1997) J. Cell Biol. 139, 951-961), respectively. Recombinant spinophilin and neurabin interacted with endogenous PP1 and also with each other when co-expressed in HEK293 cells. Spinophilin residues 427-470, or homologous neurabin residues 436-479, were sufficient to bind PP1 in gel overlay assays, and selectively bound PP1gamma(1) from a mixture of brain protein phosphatase catalytic subunits; additional N- and C-terminal sequences were required for potent inhibition of PP1. Immunoprecipitation of spinophilin or neurabin from crude brain extracts selectively coprecipitated PP1gamma(1) over PP1beta. Moreover, immunoprecipitation of PP1gamma(1) from brain extracts efficiently coprecipitated spinophilin and neurabin, whereas PP1beta immunoprecipitation did not. Thus, PP1(A) holoenzymes containing spinophilin and/or neurabin target specific neuronal PP1 isoforms, facilitating efficient regulation of synaptic phosphoproteins.
Details
- Title: Subtitle
- Brain Actin-associated Protein Phosphatase 1 Holoenzymes Containing Spinophilin, Neurabin, and Selected Catalytic Subunit Isoforms
- Creators
- Leigh B MacMillanMartha A BassNikki ChengEric F HowardMasaaki TamuraStefan StrackBrian E WadzinskiRoger J Colbran
- Resource Type
- Journal article
- Publication Details
- The Journal of biological chemistry, Vol.274(50), pp.35845-35854
- DOI
- 10.1074/jbc.274.50.35845
- PMID
- 10585469
- NLM abbreviation
- J Biol Chem
- ISSN
- 0021-9258
- eISSN
- 1083-351X
- Language
- English
- Date published
- 12/10/1999
- Academic Unit
- Pathology; Iowa Neuroscience Institute; Neuroscience and Pharmacology
- Record Identifier
- 9984040472402771
Metrics
25 Record Views