Cell-lineage-specific expression of the mouse hsp68 gene during embryogenesis.

Transcription of the mouse hsp68 and hsc70 genes in embryonal carcinoma cells, various embryonic and extraembryonic tissues, and some adult tissues has been assessed using cloned probes to the mouse hsp68 gene. The results from Northern blots showed that both F9 and P19 cells respond in the expected manner to a heat shock. Hsp68 expression was only detected in heat-induced F9 and P19 cells. Hsc70 transcripts were present in uninduced cells and their levels increased after induction. In adult tissues, the hsp68 gene was expressed constitutively in the kidney. A different hsp68-like transcript was detected at significant levels in adult testes. Constitutive expression of hsp68 was observed in both the placenta (beginning at Day 8.5) and yolk sac (beginning at Day 11.5). No hsp68 expression was detected in embryonic tissues until Day 15.5. Expression of the mouse hsp68 gene during embryogenesis suggests that it may play some role in development.