Acetylation of GAGA factor modulates its interaction with DNA.
GAGA is a Drosophila transcription factor that shows a high degree of post-translational modification. Here, we show that GAGA factor is acetylated in vivo. Lysine residues K325 and K373 on basic regions BR1 and BR3 of the DNA binding domain, respectively, are shown to be acetylated by PCAF. While BR1 is strictly required to stabilize DNA binding, BR3 is dispensable. However, acetylation of both lysine residues, either alone or in combination, weakens the binding to DNA. Despite the high degree of conservation of K325 and K373 in flies, their mutation to glutamine does not affect DNA binding. Molecular dynamics simulations, using acetylated K325 and a K325Q mutant of GAGA DNA binding domain in complex with DNA, are fully consistent with these results and provide a thermodynamic explanation for this observation. We propose that while K325 and K373 are not essential for DNA binding they have been largely conserved for regulatory purposes, thus highlighting a key regulatory system for GAGA factor in flies.
Aran-Guiu
Xavier
X
Institut de Biologia Molecular de Barcelona-CSIC and Institute for Research in Biomedicine Barcelona, Parc Científic de Barcelona, Baldiri Reixac 10-12, Barcelona, Spain.
Ortiz-Lombardía
Miguel
M
Oliveira
Eliandre
E
Bonet Costa
Carles
C
Odena
Maria Antonia
MA
Bellido
David
D
Bernués
Jordi
J
D000107:Acetylation; D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000166:cytology / Q000235:genetics; D004926:Escherichia coli; D051548:Histone Acetyltransferases / Q000378:metabolism; D008239:Lysine / Q000378:metabolism; D011485:Protein Binding; D014157:Transcription Factors / Q000378:metabolism*; D000099224:p300-CBP-Associated Factor
D004247:DNA; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D051548:Histone Acetyltransferases; D008239:Lysine; D014157:Transcription Factors; C063460:Trl protein, Drosophila; C470557:GCN5 protein, Drosophila; D000099224:p300-CBP-Associated Factor