Student or educator? Sign up with your school email and get 6 months of Pro free.
Cited by 348

The DOI matches its Crossref record.

Ca2+-dependent protein phosphorylation system in membranes from various tissues, and its activation by "calcium-dependent regulator".

Open access
Schulman, H, Greengard, P·1978·Proceedings of the National Academy of Sciences

Abstract

Analysis of membranes from a variety of tissues has revealed a widespread distribution of a protein phosphorylation system dependent on the presence of both Ca2+ and "calcium-dependent regulator" (CDR). This protein phosphorylation system has been studied in some detail in nervous tissue. Neuronal membranes contain a protein phosphorylation system that requires Ca2+ and a soluble heat-stable protein [Schulman, H. & Greengard, P. (1978) Nature (London) 271, 478--479]. This protein has been purified to homogeneity from bovine cerebral cortex, with use of an assay based on its ability to stimulate Ca2+-dependent protein phosphorylation in membranes. This protein kinase activator appears to be identical to CDR of cyclic nucleotide phosphodiesterase. Throughout its purification, this single entity was found to activate both Ca2+-dependent protein kinase and cyclic nucleotide phosphodiesterase. The kinase activator purified here and authentic CDR were equally effective in their ability to activate Ca2+-dependent protein kinase.

Overview

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1073/pnas.75.11.5432

Cites

Statistics

Verification

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Citations

Cited by

See all 348

Metadata

Authors
Schulman, H., & Greengard, P.
Venue
Proceedings of the National Academy of Sciences
Published
1978-11
Volume
75
Issue
11
Pages
5432-5436
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
OpenAlex
W2122503622
Cited by
348
References
0
FWCI
18.63
Type
journal article
Language
en
Open access
green

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review

How to cite

Cite CoChat for the checks on this page, and the paper for its own findings.

This page
CoChat. (2026). Citation check: Ca2+-dependent protein phosphorylation system in membranes from various tissues, and its activation by "calcium-dependent regulator". https://app.cochat.ai/papers/10.1073/pnas.75.11.5432
The paper
Schulman, H., & Greengard, P. (1978). Ca2+-dependent protein phosphorylation system in membranes from various tissues, and its activation by "calcium-dependent regulator". Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.75.11.5432

Data sources

Bibliographic data: Semantic Scholar, OpenAlex, Crossref.

Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.