Aggregation Independent of N-Cadherin and Neural Cell Adhesion Molecule on Quail Myoblasts Transformed with Temperature-Sensitive Rous Sarcoma Virus

Abstract

Quail myoblasts transformed with the temperature-sensitive mutant of Rous sarcoma virus (QM-RSV cells) differentiate temperature-sensitively. At 41°C, the cells begin to fuse after about 15-18 h and form multinucleated myotubes, whereas, at 35.5°C, the cells proliferate. Tyrosine-phosphorylation relates to this temperature-sensitive differentiation. In the course of the investigation of QM-RSV cells, when QM-RSV cells were dissociated with EDTA and shaken in DMEM, the aggregation activity was detected. This activity was expressed on the cells cultured at 41°C. but not at 35.5°C. For detailed characterization of the aggregation, cells from which cadherin and/or neural cell adhesion molecule (NCAM) were removed by trypsin treatment were used. It was then observed that temperature-sensitive and calcium-dependent aggregation activity was expressed on the cells treated with trypsin and EDTA (TE-cells), although the TE-cells did not retain either aggregation molecule. The aggregation activity began to be expressed at 2-4 h after temperature shift and increased with the differentiation. The expression of the activity related to the tyrosine-phosphorylation of some protein. The aggregation of TE-cells was completely inhibited by D(+)-mannose, D(+)-glucose, and N-acetyl-D-glucosamine, but D(+)-galactose did not affect the aggregation. Thus, the present results suggest that the aggregation of mannose specific C-type animal lectin recognized on TE-cells relates to the early stage of the differentiation of QM-RSV cells.

Key Words:

• Calcium-dependent aggregation
• myogenic differentiation
• animal lectin