Related Experiment Video
Updated: Sep 17, 2026

Analysis of the c-KIT Ligand Promoter Using Chromatin Immunoprecipitation
Published on: June 27, 2017
In situ localization of cAMP-dependent protein kinases in nuclear and chromosomal substructures: relation to
B Trinczek1, M Robert-Nicoud, G Schwoch
1Clinical Biochemistry, University of Göttingen, Germany.
Abstract:
Catalytic (C) and regulatory subunits (RI, RII) of cAMP-dependent protein kinase (PKA) were localized in cell nuclei of various rat tissues by immunogold electron microscopy. A specific labeling within the interchromatin space was found to be associated with perichromatin fibrils, interchromatin granules, and coiled bodies. Condensed chromatin and perichromatin granules were not labeled. In the nucleolus, most gold particles were found in the dense fibrillar component. Quantitation of labeling densities for the C-subunit from cells at different stages of spermatogenesis indicated that the nuclear concentration of PKA varies inversely with the amount of condensed chromatin. No parallel alterations in C-immunoreactivities were observed in the cytoplasm. Immunofluorescence studies on polytene chromosomes of Chironomus thummi with a confocal laser scanning microscope showed a significantly more intense labeling of the C-subunit in transcriptionally active sites (puffs) as compared to inactive bands. Our results indicate that local concentrations of PKA in the nucleus have physiological significance in the control of gene activity. In addition, they suggest that PKA plays a regulatory role also in RNA processing.
Related Concept Videos
Chromatin Position Affects Gene Expression
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the timing and level of...
RNA Polymerase II Accessory Proteins
Cell Specific Gene Expression
MAPK Signaling Cascades
cAMP-dependent Protein Kinase Pathways
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...

