dimerization and DNA binding alter phosphorylation of Fos and Jun

Journal Article · Thu Jul 15 00:00:00 EDT 1993 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.90.14.6766· OSTI ID:5852552

Abate, C; Baker, S J; Curran, T ^[1]; Lees-Miller, S P; Anderson, C W ^[2]; Marshak, D R ^[3]

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1. Roche Research Center, Nutley, NJ (United States)
2. Brookhaven National Laboratory, Upton, NY (United States)
3. Cold Spring Harbor Laboratory, NY (United States)

Fos and Jun form dimeric complexes that bind to activator protein 1 (AP-1) DNA sequences and regulate gene expression. The levels of expression and activities of these proteins are regulated by a variety of extracellular stimuli. They are thought to function in nuclear signal transduction processes in many different cell types. The role of Fos and Jun in gene transcription is complex and may be regulated in several ways including association with different dimerization partners, interactions with other transcription factors, effects on DNA topology, and reduction/oxidation of a conserved cysteine residue in the DNA-binding domain. In addition, phosphorylation has been suggested to control the activity of Fos and Jun. Here the authors show that phosphorylation of Fos and Jun by several protein kinases is affected by dimerization and binding to DNA. Jun homodimers are phosphorylated efficiently by casein kinase II, whereas Fos-Jun heterodimers are not. DNA binding also reduces phosphorylation of Jun by casein kinase II, p34[sup cdc2] (cdc2) kinase, and protein kinase C. Phosphorylation of Fos by cAMP-dependent protein kinase and cdc2 is relatively insensitive to dimerization and DNA binding, whereas phosphorylation of Fos and Jun by DNA-dependent protein kinase is dramatically stimulated by binding to the AP-1 site. These results imply that different protein kinases can distinguish among Fos and Jun proteins in the form of monomers, homodimers, and heterodimers and between DNA-bound and non-DNA-bound proteins. Thus, potentially, these different states of Fos and Jun can be recognized and regulated independently by phosphorylation. 44 refs., 4 figs.

• OSTI ID: 5852552
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Vol. 90:14; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
DNA
CHEMICAL BONDS
TRANSCRIPTION FACTORS
DIMERIZATION
PHOSPHORYLATION
GENE REGULATION
PHOSPHOTRANSFERASES
CHEMICAL REACTIONS
ENZYMES
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PHOSPHORUS-GROUP TRANSFERASES
POLYMERIZATION
PROTEINS
TRANSFERASES
550400* - Genetics
550200 - Biochemistry