Previous Article | Next Article ![]()
Molecular and Cellular Biology, July 2000, p. 4870-4878, Vol. 20, No. 13
Novartis Institute for Biomolecular Research,
Summit, New Jersey1; Novartis
Agricultural Biotechnology Research Unit, Research Triangle Park, North
Carolina2; and Albert Einstein College
of Medicine, Bronx, New York3
Received 4 November 1999/Returned for modification 10 January
2000/Accepted 13 March 2000
RAF kinase is a family of isoforms including A-RAF, B-RAF, and
C-RAF. Despite the important role of RAF in cell growth and proliferation, little evidence exists for isoform-specific function of
RAF family members. Using Western analysis and immunogold labeling, A-RAF was selectively localized in highly purified rat liver
mitochondria. Two novel human proteins, which interact specifically
with A-RAF, were identified, and the full-length sequences are
reported. These proteins, referred to as hTOM and hTIM, are similar to
components of mitochondrial outer and inner membrane protein-import
receptors from lower organisms, implicating their involvement in the
mitochondrial transport of A-RAF. hTOM contains multiple
tetratricopeptide repeat (TPR) domains, which function in
protein-protein interactions. TPR domains are frequently present in
proteins involved in cellular transport systems. In contrast, protein
14-3-3, an abundant cytosolic protein that participates in many facets
of signal transduction, was found to interact with C-RAF but not with
A-RAF N-terminal domain. This information is discussed in view of the
important role of mitochondria in cellular functions involving energy
balance, proliferation, and apoptosis and the potential role of A-RAF
in regulating these systems.
0270-7306/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
Isoform-Specific Localization of A-RAF in
Mitochondria


*
Corresponding author. Mailing address: Novartis
Institute for Biomedical Research, 556 Morris Ave., LSB3165, Summit, NJ
07901. Phone: (908) 277-5697. Fax: (908) 277-4756. E-mail:
lawrence.wennogle{at}pharma.novartis.com.
Present address: InforMax Inc., North Bethesda, MD 20852.
Present address: NADDI, Scripps Institute, La Jolla, CA 92037.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»