Identification of a yeast protein with properties similar to those of the immunoglobulin heavy-chain enhancer-binding protein NF-muE3.

Abstract

We demonstrate that Saccharomyces cerevisiae cells possess a 33-41-kilodalton protein with DNA-binding properties remarkably similar to those of the immunoglobulin enhancer-binding protein NF-,uE3. We further show that the ,uE3-binding site functions as an upstream activating sequence in yeast cells, stimulating transcription from a truncated CYCI promoter. These data suggest that the yeast protein, designated YEB-3, and NF-,tE3 are functionally related and perhaps evolutionarily conserved.

The plant G box promoter sequence activates transcription in Saccharomyces cerevisiae and is bound in vitro by a yeast activity similar to GBF, the plant G box binding factor.

“…The E3 site (TCATGTGG) differs from the G box by two C -T transitions. Like the plant G box sequence, this motif can also activate expression in yeast from the truncated CYC 1 -lacZ construct, although its activity is significantly lower than the G box sequences described here (Beckmann and Kadesch, 1989).…”

“…Other workers have also identified yeast DNA binding activities that resemble yGBF (Bram and Kornberg, 1987;Beckmann and Kadesch, 1989;Chodosh et al, 1989;Vogel et al, 1989), although the sites recognized by these activities do not match the G box as closely as the sequences shown in Table I. The yeast factor described by Chodosh et al (1989) and Bram and Kornberg (1987) interacts with a near-palindromic sequence CCACGTGA, the binding site of the mammalian transcription factor USF or MLTF (Carthew et al, 1985;Sawadogo and Roeder, 1985;Chodosh et al, 1986).…”

“…The yeast factor described by Chodosh et al (1989) and Bram and Kornberg (1987) interacts with a near-palindromic sequence CCACGTGA, the binding site of the mammalian transcription factor USF or MLTF (Carthew et al, 1985;Sawadogo and Roeder, 1985;Chodosh et al, 1986). Beckmann and Kadesch (1989) identified a yeast factor with similar properties to NFItE3, a mammalian DNA binding protein interacting with the E3 site of the immunoglobulin heavy chain enhancer. The E3 site (TCATGTGG) differs from the G box by two C -T transitions.…”

CPF1, a yeast protein which functions in centromeres and promoters.

“…This is in agreement with the observation that protein -DNA complexes formed with S. cerevisiae extracts and DNA fragments containing the CDEI octanucleotide often resolve in band-shift analyses into a doublet. It is open as to whether the 33-41 kd S.cerevisiae protein (YEB-3) which binds in vitro to a CDEI-like sequence (Beckmann and Kadesch, 1989) is a degradation product of CPF1 or a different protein. This was concluded from a comparison of peptide sequence data with the sequence of the cloned gene.…”

TFE3: a helix-loop-helix protein that activates transcription through the immunoglobulin enhancer muE3 motif.

“…The site was also shown to contribute to the low level of enhancer activity observed in non-B cells (Kiledjian et al 1988). The corresponding DNA-binding activity, NF-~E3, was thought initially to represent a single protein ; however, purification has since revealed perhaps as many as three related proteins of similar size (42.5-45 kD) that interact with the motif in various oligomeric forms (Peterson and Calame 1989), and a related activity has even been described in yeast (Beckmann and Kadesch 1989). For simplicity, we will use the term NF-I~E3 to describe the mammalian IxE3-binding activity derived from nuclear extracts, which may represent multiple proteins.…”