The hypothesis set forth in this proposal is that colligin/hsp47 is one of the cellular proteins that serves to provide the molecular basis for stress tolerance. As such, we propose that colligin/hsp47 belongs to a ubiquitous family of proteins, (molecular chaperones), whose proposed role is to mediate the folding and assembly of other proteins into oligomeric structures. Since colligin/hsp47's major substrate has been shown to be various collagen types, hsp47 is seen to have a transient exposure to procollagens during synthesis, the unfolding and refolding that occurs with transport from the endoplasmic reticulum, and during recovery from stresses such as heat shock. In order to test these hypotheses and add further to our understanding of stress tolerance we will utilize tissue culture, Western blot analysis, Northern blot analyses, protein binding, immunocytochemistry and electron microscopy to accomplish the following specific aims during a 3-year period. First we will verify that colligin/hsp47 interacts with intracellular collagen and determine it's binding to evolving and completed nascent pro-alpha-1 type I chains. Second, we will determine the temporal and compartmental expression of colligin/hsp47 with procollagen I. Next, we will determine whether the association or disassociation of colligin/hsp47-collagens requires an input of energy and is commensurate with the rate of procollagen chain synthesis. Finally, we will prove that there exists a strategic placement of sequences in procollagen of unusually persistent association with hsp47. Furthermore, that the association/disassociation from these sites occurs in a sequential manner that is compatible with procollagen I folding and oligomerization, and corresponding with the action of a chaperone protein. These studies will provide a better understanding of some of the fundamental mechanisms involving ligament and tendon injury. In addition, these studies will provide important information needed for establishing effective therapeutic procedures for the treatment of connective tissue disorders, particularly those of ligaments and tendons.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE008648-05
Application #
3222451
Study Section
Oral Biology and Medicine Subcommittee 1 (OBM)
Project Start
1988-09-01
Project End
1994-08-31
Budget Start
1992-09-01
Budget End
1993-08-31
Support Year
5
Fiscal Year
1992
Total Cost
Indirect Cost
Name
University of Maryland Baltimore
Department
Type
Schools of Dentistry
DUNS #
003255213
City
Baltimore
State
MD
Country
United States
Zip Code
21201
Hebert, C; Norris, K; Della Coletta, R et al. (1999) Cell surface colligin/Hsp47 associates with tetraspanin protein CD9 in epidermoid carcinoma cell lines. J Cell Biochem 73:248-58
Coletta, R D; Almeida, O P; Ferreira, L R et al. (1999) Increase in expression of Hsp47 and collagen in hereditary gingival fibromatosis is modulated by stress and terminal procollagen N-propeptides. Connect Tissue Res 40:237-49
Coletta, R D; Almeida, O P; Reynolds, M A et al. (1999) Alteration in expression of MMP-1 and MMP-2 but not TIMP-1 and TIMP-2 in hereditary gingival fibromatosis is mediated by TGF-beta 1 autocrine stimulation. J Periodontal Res 34:457-63
Sauk, J J; Norris, K; Hebert, C et al. (1998) Hsp47 binds to the KDEL receptor and cell surface expression is modulated by cytoplasmic and endosomal pH. Connect Tissue Res 37:105-19
Ferreira, L R; Norris, K; Smith, T et al. (1996) Hsp47 and other ER-resident molecular chaperones form heterocomplexes with each other and with collagen type IV chains. Connect Tissue Res 33:265-73
D'Errico, J A; Sauk, J J; Prince, C W et al. (1995) Osteopontin adhesion receptors on gingival fibroblasts. J Periodontal Res 30:34-41
Smith, T; Ferreira, L R; Hebert, C et al. (1995) Hsp47 and cyclophilin B traverse the endoplasmic reticulum with procollagen into pre-Golgi intermediate vesicles. A role for Hsp47 and cyclophilin B in the export of procollagen from the endoplasmic reticulum. J Biol Chem 270:18323-8
Hu, G; Gura, T; Sabsay, B et al. (1995) Endoplasmic reticulum protein Hsp47 binds specifically to the N-terminal globular domain of the amino-propeptide of the procollagen I alpha 1 (I)-chain. J Cell Biochem 59:350-67
Sun, D; Sauk, J J; Archibald, D W (1994) Decrease of heat shock protein 27/28 with heat stress in HTLV-I-transformed cells. Exp Mol Pathol 60:147-57
Ferreira, L R; Norris, K; Smith, T et al. (1994) Association of Hsp47, Grp78, and Grp94 with procollagen supports the successive or coupled action of molecular chaperones. J Cell Biochem 56:518-26

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