A complex interplay of positive and negative elements is responsible for the different transcriptional activity of liver NF1 variants.
A full-length cDNA of the rat liver Nuclear Factor 1 (NF1L21) has been cloned and expressed in S. cerevisiae to analyse the architecture of its activation domain. NF1L21 displays a specific DNA-binding activity, as well as the ability to activate transcription from an artificial NF 1-responsive promoter in yeast. Interaction of two or more NF1L21 molecules with multiple sites on the same promoter activated transcription in a synergistic fashion. Functional analysis of the activation domain of NF1L21 reveals a tripartite structure. Two distinct positive elements are required for NF1L21 -mediated transcription activation. A proline-rich element sandwiched between these two positive domains attenuates their transactivation potential. A shorter NF1L variant (NFlL4) in which the distal positive element is replaced by a different sequence was also isolated. NF1L4 displays the same DNA-binding activity and dimerisation properties as NF1L21, but is unable to activate transcription in yeast.
Monaci
P
P
Istituto di Ricerche di Biologia Molecolare P Angeletti, (Roma), Italy.
Nuzzo
M
M
Stampfli
S
S
Tollervey
D
D
De Simone
V
V
Nicosia
A
A
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D006801:Humans; D008099:Liver / Q000502:physiology*; D008969:Molecular Sequence Data; D051839:NFI Transcription Factors; D009687:Nuclear Proteins; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D051381:Rats; D011993:Recombinant Fusion Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*; D015533:Transcriptional Activation / Q000235:genetics*; D051840:Y-Box-Binding Protein 1
D022762:CCAAT-Enhancer-Binding Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D051839:NFI Transcription Factors; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D051840:Y-Box-Binding Protein 1; C070856:YBX1 protein, human