Microinjection of fos-specific antibodies blocks DNA synthesis in fibroblast cells.

摘要: Transcription of the protooncogene c-fos is increased greater than 10-fold within minutes treatment fibroblasts with serum or purified growth factors. Recent experiments mouse 3T3 cell lines containing inducible fos antisense RNA constructs have shown that induced transcripts cause either a marked inhibition in continuously proliferating cells or, conversely, minimal effect except during transition from quiescent (G0) state into cycle. Since intracellular production large amounts does not completely block gene expression, we microinjected affinity-purified antibodies raised against to determine whether and when cycle expression was required for proliferation. Using this independent method, found efficiently blocked serum-stimulated DNA synthesis injected up 6 8 h after stimulation REF-52 fibroblasts. Furthermore, were asynchronously growing cells, consistently number prevented synthesizing nonspecific immunoglobulins. Thus, whereas activity may be necessary G0 G1 cycle, its function also early portion allow subsequent synthesis.