Identification of an intracellular protein that specifically interacts with photoaffinity-labeled oncogenic p21 protein

Journal Article · Wed Nov 01 00:00:00 EST 1989 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.86.22.8678· OSTI ID:6957947

Lee, G ^[1]; Ronai, Z A ^[2]; Pincus, M R ^[3]; Brandt-Rauf, P W; Weinstein, I B ^[4]; Murphy, R B ^[5]; Delohery, T M ^[4]; Nishimura, S; Yamaizumi, Z ^[6]

---

1. New York Univ., NY (USA) Columbia Univ. College of Physicians and Surgeons, New York, NY (USA)
2. Columbia Univ. College of Physicians and Surgeons, New York, NY (USA) American Health Foundation, Valhalla, NY (USA)
3. New York Univ., NY (USA) State Univ. of New York Health Science Center, Syracuse (USA)
4. Columbia Univ. College of Physicians and Surgeons, New York, NY (USA)
5. New York Univ., NY (USA) Cornell Univ. Medical College, White Plains, NY (USA)
6. National Cancer Center Research Institute, Tokyo (Japan)

An oncogenic 21-kDa (p21) protein (Harvey RAS protein with Val-12) has been covalently modified with a functional reagent that contains a photoactivatable aromatic azide group. This modified p21 protein has been introduced quantitatively into NIH 3T3 cells using an erythrocyte-mediated fusion technique. The introduced p21 protein was capable of inducing enhanced pinocytosis and DNA synthesis in the recipient cells. To identify the putative intracellular protein(s) that specifically interact with modified p21 protein, the cells were pulsed with ({sup 35}S)methionine at selected times after fusion and then UV-irradiated to activate the azide group. The resulting nitrene covalently binds to amino acid residues in adjacent proteins, thus linking the p21 protein to these proteins. The cells were then lysed, and the lysate was immunoprecipitated with the anti-p21 monoclonal antibody Y13-259. The immunoprecipitate was analyzed by SDS/PAGE to identify p21 - protein complexes. By using this technique, the authors found that three protein complexes of 51, 64, and 82 kDa were labeled specifically and reproducibly. The most prominent band is the 64-kDa protein complex that shows a time-dependent rise and fall, peaking within a 5-hr period after introduction of the p21 protein the cells. These studies provide evidence that in vitro the p21 protein becomes associated with a protein whose mass is about 43 kDa. They suggest that the formation of this complex may play a role in mediating early events involved with cell transformation induced by RAS oncogenes.

• OSTI ID: 6957947
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Vol. 86:22; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ONCOGENES
BIOCHEMISTRY
PROTEINS
BIOLOGICAL RADIATION EFFECTS
AZIDES
CROSS-LINKING
ELECTROPHORESIS
EXTREME ULTRAVIOLET RADIATION
FIBROBLASTS
IN VITRO
METHIONINE
PRECIPITATION
SULFUR 35
AMINO ACIDS
ANIMAL CELLS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CHEMISTRY
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTROMAGNETIC RADIATION
EVEN-ODD NUCLEI
GENES
ISOTOPES
LIGHT NUCLEI
LIPOTROPIC FACTORS
NITROGEN COMPOUNDS
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
POLYMERIZATION
RADIATION EFFECTS
RADIATIONS
RADIOISOTOPES
SEPARATION PROCESSES
SOMATIC CELLS
SULFUR ISOTOPES
ULTRAVIOLET RADIATION
550201* - Biochemistry- Tracer Techniques