The extracellular matrix plays a vital role in the normal function of complex organisms. It is implicated in organogenesis, cell differentiation, metastasis, neuronal guidance, wound healing and protective functions. A specialized sheet-like structure of the extracellular matrix, the basal lamina, underlies various tissues and is in intimate contact with the plasma membrane of the overlying cells. The major components of this structure are laminin, type IV collagen, heparan sulfate proteoglycan and entactin. The molecular structures of these molecules have been largely determined by recombinant DNA approaches and the biological activity of each molecule is being elucidated. Transmembrane receptors have been identified and characterized for laminin and type IV collagen. These transmembrane receptors are believed to be responsible for transmitting information from the extracellular to the intracellular compartment and thereby eliciting specific cellular responses. The biological properties of entactin which include promotion of cell attachment, chemotaxis, phagocytosis and neutrophil degranulation are only now being uncovered. Furthermore , entactin appears to be important in organizing the extracellular matrix through its interactions with laminin, type IV collagen and fibronectin. It is the purpose of this project to extend the studies on entactin and to correlate in vitro observations with in vivo biological functions. The experiments to be performed include (a) mapping the functional domains (b) isolation and characterization of transmembrane and other receptors (c) analysis of its role in the morphogenesis and development of the eye and (d) exploring its function in hemostasis and wound healing. A combination of immunological, biochemical and genetic approaches will be used to solve these problems. It is hoped that the results obtained will contribute to our understanding of basal lamina function at the molecular level in normal development and in pathological conditions.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA021246-17
Application #
2086934
Study Section
Cellular Biology and Physiology Subcommittee 1 (CBY)
Project Start
1978-02-01
Project End
1997-04-30
Budget Start
1995-05-01
Budget End
1996-04-30
Support Year
17
Fiscal Year
1995
Total Cost
Indirect Cost
Name
University of Pittsburgh
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
053785812
City
Pittsburgh
State
PA
Country
United States
Zip Code
15213
Dong, Lijin; Chen, Yong; Lewis, Marcia et al. (2002) Neurologic defects and selective disruption of basement membranes in mice lacking entactin-1/nidogen-1. Lab Invest 82:1617-30
Gresham, H D; Graham, I L; Griffin, G L et al. (1996) Domain-specific interactions between entactin and neutrophil integrins. G2 domain ligation of integrin alpha3beta1 and E domain ligation of the leukocyte response integrin signal for different responses. J Biol Chem 271:30587-94
Durkin, M E; Wewer, U M; Chung, A E (1995) Exon organization of the mouse entactin gene corresponds to the structural domains of the polypeptide and has regional homology to the low-density lipoprotein receptor gene. Genomics 26:219-28
Dong, L J; Hsieh, J C; Chung, A E (1995) Two distinct cell attachment sites in entactin are revealed by amino acid substitutions and deletion of the RGD sequence in the cysteine-rich epidermal growth factor repeat 2. J Biol Chem 270:15838-43
Wu, C; Chung, A E; McDonald, J A (1995) A novel role for alpha 3 beta 1 integrins in extracellular matrix assembly. J Cell Sci 108 ( Pt 6):2511-23
Rasmussen, M V; Klein, N W; Abrahamson, D R et al. (1994) Effects of laminin monoclonal antibodies on the development of cultured rat embryos. Teratology 49:20-8
Donaldson, D J; Mahan, J T; Tsilibary, E C et al. (1994) Migratory interaction of amphibian epidermal cells with components of the basement membrane. J Cell Physiol 158:79-86
Hsieh, J C; Wu, C; Chung, A E (1994) The binding of fibronectin to entactin is mediated through the 29 kDa amino terminal fragment of fibronectin and the G2 domain of entactin. Biochem Biophys Res Commun 199:1509-17
Zagris, N; Stavridis, V; Chung, A E (1993) Appearance and distribution of entactin in the early chick embryo. Differentiation 54:67-71
Yelian, F D; Edgeworth, N A; Dong, L J et al. (1993) Recombinant entactin promotes mouse primary trophoblast cell adhesion and migration through the Arg-Gly-Asp (RGD) recognition sequence. J Cell Biol 121:923-9

Showing the most recent 10 out of 25 publications