V. Pingoud et al., HETEROGENEITY OF TERNARY COMPLEX FACTORS IN HELA-CELL NUCLEAR EXTRACTS, The Journal of biological chemistry, 269(37), 1994, pp. 23310-23317
Ternary complex factors (TCFs) interact with the serum response factor
and DNA containing the c-fos serum response element to form a ternary
complex that mediates induction of c-fos. TCF activities were partial
ly purified from HeLa cell nuclear extracts by DNA-cellulose and anion
-exchange chromatography followed by two-dimensional gel electrophores
is. Four different protein spots (p60(TCF), p62(TCF), p62.5(TCF), and
p64(TCF)) show renaturable TCF activity. One, p62(TCF), was indistingu
ishable from the Ets protein Elk-1 in gel shift analyses, while none o
f the HeLa TCFs resembled the other cloned TCFs, SAP-1a and SAP-1b. In
two-dimensional gel analysis, Elk-1, SAP-1a, and SAP-1b, displayed di
fferent pI and M(r) values and in vitro synthesized Elk-1 comigrated w
ith the p62(TCF) spot. Both reacted with Elk-1 specific antisera, as d
id the major proportion of TCF activity present in HeLa crude extracts
. We conclude that p62(TCF) is composed of Elk-1, whereas the identiti
es of the other identified TCFs (p60(TCF), P62.5(TCF), and p64(TCF)) a
re still unknown.