TY - JOUR
T1 - An immunocytochemical study of the routes of secretion of collagen and phosphophoryn from odontoblasts into dentin
AU - Rabie, A. M.
AU - Veis, Arthur
N1 - Funding Information:
*This work was supported by grants DE 01374 (NIDR) and AR 13921 (NIAMSD) to AV from the National Institutes of Health. **This work is taken in part from studies presented by A. M. Rabie. in a Ph.D. Dissertation submitted to the Graduate School of Northwestern University, Evanston in December, 1991. Present Address: Dr. A. B. M. Rabie The Prince Philip Dental Hospital, Department of Children's Dentistry and Orthodontics, 34 Hospital Road, Hong Kong ***Author to whom correspondence should be addressed. Phone: 312-503-8296 FAX: 312-503-2544
PY - 1995
Y1 - 1995
N2 - Polyclonal antibodies to rat incisor phosphophoryns and to the amino-telopeptide of the α (I)-chain of type I collagen were used to follow the pathways of movement of collagen 1 (COL 1) and phosphophoryns (PP) from synthesis in the odontoblast to secretion into the mineralized dentin. The antibodies were detected at the transmission electron microscopic level by their reaction with Protein A-colloidal gold conjugates. Special care was given in specimen preparation to retention of maximal antigenicity during fixation while maintaining cellular and extracellular ultrastructure at the mineralization front (MF) in nondemineralized sections. Intracellularly, COL1 and PP were detected within the endoplasmic reticulum (ER), the Golgi (G) and secretory granules (SO). However, as determined by double-immunolabeling with different size gold particles the COL1 and PP were not found together within the same ER, G or SG compartments. PP was localized within the tubular ER, round-shaped transitional vesicles, the Golgi and in narrow asymmetric SG. These asymmetric SG were found in abundance in the odontoblastic process. PP secretion from these vesicles was near the MF at the predentin-dentin boundary. COL1 was localized within rosette form ER compartments, the Golgi and in large, distinctive SG. COL 1 was deposited at the cell-predentin boundary. No COL 1 SG were seen within the odontoblastic process near the MF. In the region of the MF, prior to mineralization, the PP was localized along the surfaces of the COL1 fibrils of the predentin. The mineral phase etched surfaces revealed both COL 1 - and abundant mineral-associated PP. These data support the hypotheses that, in dentin, the interaction between COL I and PP may initiate crystal nucleation and that additional interactions between PP and the growing crystals may modulate the crystal growth pattern and crystal size.
AB - Polyclonal antibodies to rat incisor phosphophoryns and to the amino-telopeptide of the α (I)-chain of type I collagen were used to follow the pathways of movement of collagen 1 (COL 1) and phosphophoryns (PP) from synthesis in the odontoblast to secretion into the mineralized dentin. The antibodies were detected at the transmission electron microscopic level by their reaction with Protein A-colloidal gold conjugates. Special care was given in specimen preparation to retention of maximal antigenicity during fixation while maintaining cellular and extracellular ultrastructure at the mineralization front (MF) in nondemineralized sections. Intracellularly, COL1 and PP were detected within the endoplasmic reticulum (ER), the Golgi (G) and secretory granules (SO). However, as determined by double-immunolabeling with different size gold particles the COL1 and PP were not found together within the same ER, G or SG compartments. PP was localized within the tubular ER, round-shaped transitional vesicles, the Golgi and in narrow asymmetric SG. These asymmetric SG were found in abundance in the odontoblastic process. PP secretion from these vesicles was near the MF at the predentin-dentin boundary. COL1 was localized within rosette form ER compartments, the Golgi and in large, distinctive SG. COL 1 was deposited at the cell-predentin boundary. No COL 1 SG were seen within the odontoblastic process near the MF. In the region of the MF, prior to mineralization, the PP was localized along the surfaces of the COL1 fibrils of the predentin. The mineral phase etched surfaces revealed both COL 1 - and abundant mineral-associated PP. These data support the hypotheses that, in dentin, the interaction between COL I and PP may initiate crystal nucleation and that additional interactions between PP and the growing crystals may modulate the crystal growth pattern and crystal size.
KW - Collagen
KW - Dentin
KW - Intracellular transport
KW - Mineralization
KW - Phosphophoryn
KW - Secretory pathways
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U2 - 10.3109/03008209509010811
DO - 10.3109/03008209509010811
M3 - Article
C2 - 15609627
AN - SCOPUS:0029186899
SN - 0300-8207
VL - 31
SP - 197
EP - 209
JO - Connective Tissue Research
JF - Connective Tissue Research
IS - 3
ER -