This research project is focused on determining the structure and function relationship of the gap junction channel and the contribution of gap junctional communication to the processes of embryonic development and differentiation. The specific objectives for this study include the following. 1. The structure and function relationship of the rat liver gap junction channels and a baculovirus-derived gap junction channel will be determined by initially isolating channel oligomers from these two sources. The oligomers will then be used for the following: (1) a characterization of their structural and biochemical properties; (2) efforts to crystallize the isolated oligomers for analysis by electron microscopy and potentially X- ray diffraction; (3) reconstitution of the oligomers into black membrane systems where the channel conductance properties of the reconstituted can be characterized biophysically; (4) to determine if the isolated oligomers contain a single gene product (homo-oligomer) or multiple gene products (hetero-oligomer); and finally (5) to determine the contribution of the sequences in the extracellular domains. 2. Gap junctional communication will be studied in a number of systems that include: Xenopus embryogenesis, mouse embryogenesis and organogenesis, implantation and parturition in the rat, and muscle differentiation using a mouse cell culture system. IN addition the contribution of gap junctional communication to some of these processes will be analyzed by modifying communication with various perturbation approaches.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37GM037904-07
Application #
3484859
Study Section
Molecular Cytology Study Section (CTY)
Project Start
1986-07-01
Project End
1995-11-30
Budget Start
1992-12-01
Budget End
1993-11-30
Support Year
7
Fiscal Year
1993
Total Cost
Indirect Cost
Name
Scripps Research Institute
Department
Type
DUNS #
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Lagree, Valerie; Brunschwig, Karin; Lopez, Patricia et al. (2003) Specific amino-acid residues in the N-terminus and TM3 implicated in channel function and oligomerization compatibility of connexin43. J Cell Sci 116:3189-201
Baruch, A; Greenbaum, D; Levy, E T et al. (2001) Defining a link between gap junction communication, proteolysis, and cataract formation. J Biol Chem 276:28999-9006
Baldo, G J; Gong, X; Martinez-Wittinghan, F J et al. (2001) Gap junctional coupling in lenses from alpha(8) connexin knockout mice. J Gen Physiol 118:447-56
Unger, V M; Kumar, N M; Gilula, N B et al. (1999) Expression, two-dimensional crystallization, and electron cryo-crystallography of recombinant gap junction membrane channels. J Struct Biol 128:98-105
Risek, B; Pozzi, A; Gilula, N B (1998) Modulation of gap junction expression during transient hyperplasia of rat epidermis. J Cell Sci 111 ( Pt 10):1395-404
Gong, X; Baldo, G J; Kumar, N M et al. (1998) Gap junctional coupling in lenses lacking alpha3 connexin. Proc Natl Acad Sci U S A 95:15303-8
Falk, M M; Gilula, N B (1998) Connexin membrane protein biosynthesis is influenced by polypeptide positioning within the translocon and signal peptidase access. J Biol Chem 273:7856-64
Falk, M M; Buehler, L K; Kumar, N M et al. (1997) Cell-free synthesis and assembly of connexins into functional gap junction membrane channels. EMBO J 16:2703-16
Risek, B; Gilula, N B (1996) Gap junction regulation during preterm labor in the rat: multiple effects of the antiprogesterone RU486. Biol Reprod 55:525-35
Buehler, L K; Stauffer, K A; Gilula, N B et al. (1995) Single channel behavior of recombinant beta 2 gap junction connexons reconstituted into planar lipid bilayers. Biophys J 68:1767-75

Showing the most recent 10 out of 36 publications