Effects of extracellular calcium concentration on protein synthesis in Aedes albopictus cells

The influence of extracellular calcium concentration on mosquito cells was investigated in Aedes albopictus cells cultured in a medium with different amounts of calcium, Protein synthesis in cells incubated in low calcium cul ture medium was inhibited when compared to control cells, This inhibition w as reversed by addition of calcium to the culture medium, Two calcium-induc ed proteins of approximately 70,000 and 80,000 daltons were detected when c alcium was added to the extracellular medium of cells incubated in low calc ium medium for longer than 2 h, Northern-blot analysis indicated that Hsp70 (heat shock protein of 70,000 dalton) specific mRNA is present in cells th at were cultured in low calcium medium suggesting that the 70,000 dalton pr otein is a member of the Hsp70 family, Our results indicate that extracellu lar calcium concentration can modify the gene expression pattern in A, albo pictus cells and the absence of calcium in the culture medium could be cons idered a stress factor, (C) 1998 Wiley-Liss, Inc.