Cooperative binding of the E2 protein of bovine papillomavirus to adjacent E2-responsive sequences

Monini, Paolo; Grossman, Steven R.; Pepinsky, Blake; Androphy, Elliot J.; Laimins, Laimonis A.

doi:10.1128/jvi.65.4.2124-2130.1991

Cited by 50 publications

(43 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cooperativity parameter for the binding of CI to O1O2 DNA was determined from the scanned data of the autoradiogram ( Fig. 2I) according to Monini et al [37]. To study CI binding stoichiometry, a gel shift assay was performed using essentially the same method (see above), except that reaction mixtures contained higher CI concentrations (0.2-2 lm) and 0.4 lm cold O1 DNA along with 0.1 nm 32 P-labeled O1 DNA.…”

Section: Gel Shift Assaymentioning

confidence: 99%

Physicochemical properties and distinct DNA binding capacity of the repressor of temperate Staphylococcus aureus phage φ11

Ganguly¹,

Das²,

Bandhu

et al. 2009

The FEBS Journal

View full text Add to dashboard Cite

The basic regulatory elements that most temperate phages use for the establishment and maintenance of their lysogeny are the phage-encoded repressor and the cognate operator DNA [1][2][3][4][5][6][7][8][9][10][11][12]. A temperate phage generally enters into the lysogenic life cycle once its repressor inhibits the transcription of the phagespecific lytic genes from the early promoter by binding to the overlapped operator DNA. Repressors of the temperate phages, although varying greatly in size and in primary sequence level, mostly harbor a DNA binding domain and an oligomerization domain. The size and type of the operator DNAs also vary from phage to phage. Although some repressors bind to operators with dyad symmetry [1,[5][6][7][8][9] or operators with direct repeats [10], other repressors bind to asymmetric operators [2,3,[11][12][13] to establish lysogeny. Interestingly, the repressor of Vibrio cholerae phage CTX/ binds to extended operators, stopping lytic growth, as well as ensuring lysogeny of this phage [4]. Although these regulatory elements have enriched both basic and applied molecular biology enormously, they have not been cloned from most temperate phages or characterized in any depth.The temperate Staphylococcus aureus phage /11 [14] harbors the cI and cro genes in a divergent orientation to that in lambdoid phages [1,8]. The sequence of the immunity region of /11, however, differs significantly from those of the lambdoid phages and other temper- The repressor protein and cognate operator DNA of any temperate Staphylococcus aureus phage have not been investigated in depth, despite having the potential to enrich the molecular biology of the staphylococcal system. In the present study, using the extremely pure repressor of temperate Staphylococcus aureus phage /11 (CI), we demonstrate that CI is composed of a-helix and b-sheet to a substantial extent at room temperature, possesses two domains, unfolds at temperatures above 39°C and binds to two sites in the /11 cI-cro intergenic region with variable affinity. The above CI binding sites harbor two homologous 15 bp inverted repeats (O1 and O2), which are spaced 18 bp apart. Several guanine bases located in and around O1 and O2 demonstrate interaction with CI, indicating that these 15 bp sites are used as operators for repressor binding. CI interacted with O1 and O2 in a cooperative manner and was found to bind to operator DNA as a homodimer. Interestingly, CI did not show appreciable binding to another homologous 15 bp site (O3) that was located in the same primary immunity region as O1 and O2. Taken together, these results suggest that /11 CI and the /11 CI-operator complex resemble significantly those of the lambdoid phages at the structural level. The mode of action of /11 CI, however, may be distinct from that of the repressor proteins of k and related phages.Abbreviations CI, repressor of temperate Staphylococcus aureus phage /11; CTD, C-terminal domain; DMS, dimethyl sulfate; DTNB, 5,5¢-dithiobis-(2-nitrobenzoic acid); NTD, N-terminal domain.

show abstract

Section: Gel Shift Assaymentioning

confidence: 99%

Physicochemical properties and distinct DNA binding capacity of the repressor of temperate Staphylococcus aureus phage φ11

Ganguly¹,

Das²,

Bandhu

et al. 2009

The FEBS Journal

View full text Add to dashboard Cite

show abstract

“…Moreover, the E2-dependent enhancer is redundant, since small deletions have little effect and larger deletions generally show a stepwise loss of activity. Since cooperation between E2 molecules has been demonstrated by physical methods (16,29) and suggested by functional analysis (39), perhaps E2 binding sites 1 to 4 were sufficient for full response in Fig. 3D as a result of being moved closer to sites 11 and 12 by removal of the intervening DNA.…”

mentioning

confidence: 90%

Regulation of early gene expression from the bovine papillomavirus genome in transiently transfected C127 cells

Szymanski

Stenlund

1991

J Virol

View full text Add to dashboard Cite

Expression of bovine papillomavirus (BPV) early gene products is required for viral DNA replication and * Corresponding author. formation of nonfunctional transcription complexes might also occur, as suggested by the finding that the E8/E2 protein can repress the basal activity of the P2 (P89) promoter (4). The E2 proteins are expressed from several different viral promoters. The E2C and E8/E2 repressors are expressed from the PS (P3080) and P3 (P89) promoters, respectively (4,

show abstract

“…In the case of activation by E2 it has been shown that whilst a single E2 palindrome only activates transcription weakly in mammalian cells, two sites can function efficiently as an E2-dependent enhancer (Hawley-Nelson et al, 1988;Spalholz et al, 1988). This synergistic effect might result from co-operative DNA binding by two E2 dimers but a high degree of co-operativity has not been observed in in vitro gel retardation assays with sites that show strong synergy in vivo (Dostatni et al, 1988;Lambert et al, 1989;Monini et al, 1991;Gauthier et al, 1991). Alternatively, the synergy might be due to co-operativity at some level of transcriptional activation, e.g.…”

Section: Introductionmentioning

confidence: 99%

Several different upstream promoter elements can potentiate transactivation by the BPV-1 E2 protein.

et al. 1991

View full text Add to dashboard Cite

The enhancer and upstream promoter regions of RNA polymerase II transcribed genes modulate the rate of transcription initiation and establish specific patterns of gene expression. Both types of region consist of clusters of DNA binding sites for nuclear proteins. To determine how efficiently the same factor can activate transcription when acting as an enhancer or promoter factor, we have studied transactivation by the BPV‐1 E2 protein, a papillomavirus transcriptional regulator. By cotransfecting a BPV‐1 E2 expression vector and a series of reporter plasmids containing well‐defined chimeric promoters we have found that whilst E2 can strongly stimulate complex promoters such as that of the HSV tk gene, it does not efficiently activate constructions containing only a TATA box and initiation site. We show that insertion of upstream promoter elements, but not of spacer DNA, between E2 binding sites and the TATA box greatly increases E2 activation. This effect was observed with more than one type of upstream promoter element, is not related to the strength of the promoter and is unlikely to result from co‐operative DNA binding by E2 and the transcription factors tested. These results would suggest that E2 has the properties of an enhancer rather than promoter factor and that in certain cases promoter and enhancer factors may affect different steps in the process of transcriptional activation.

show abstract

Cooperative binding of the E2 protein of bovine papillomavirus to adjacent E2-responsive sequences

Cited by 50 publications

References 41 publications

Physicochemical properties and distinct DNA binding capacity of the repressor of temperate Staphylococcus aureus phage φ11

Physicochemical properties and distinct DNA binding capacity of the repressor of temperate Staphylococcus aureus phage φ11

Regulation of early gene expression from the bovine papillomavirus genome in transiently transfected C127 cells

Several different upstream promoter elements can potentiate transactivation by the BPV-1 E2 protein.

Contact Info

Product

Resources

About