Nuclear size as a cell-kinetic marker for osteoblast differentiation

Roberts, W. E.; Mozsary, P. G.; Klingler, E.

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NASA NTRS · 20050000952

Nuclear size as a cell-kinetic marker for osteoblast differentiation

Roberts, W. E.·Mozsary, P. G.·Klingler, E.

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Abstract

A nuclear morphometric assay for preosteoblasts is introduced as a cell-kinetic technique, applicable to routine histological preparations of mineralized tissue. Because this method is a morphological marker for osteoblast precursor cell differentiation, it provides a new dimension for determining the mechanism of osteoblast histogenesis. Osteoblast precursors of the periodontal ligament are a mixed population of progenitors, kinetically separable into two distinct groups according to nuclear size. Preosteoblasts, the immediate proliferating precursors of osteoblasts, have large nuclei (greater than 170 micrometers3) and are derived from relatively undifferentiated fibroblastlike cells, which have smaller nuclei (less than 80 micrometers3). Increase in nuclear volume, during G1 phase of the cell cycle, is apparently a morphological manifestation of change in genomic expression. This key event in preosteoblast differentiation is related to mechanical stress/strain and may be an important rate-limiting step in osteoblast histogenesis.

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Non-NASA Center NASA Discipline Number 40-30 NASA Discipline Musculoskeletal NASA Program Space Biology Cell Nucleus/ultrastructure Osteoblasts/cytology/metabolism/ultrastructure Support, U.S. Gov't, P.H.S Support, Non-U.S. Gov't Comparative Study Male Thymidine/metabolism Methods Autoradiography Rats Animals Cell Differentiation

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Roberts, W. E., Mozsary, P. G., Klingler, E.. 1982-12-01. Nuclear size as a cell-kinetic marker for osteoblast differentiation. https://ntrs.nasa.gov/citations/20050000952

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