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* Fos/jun DNA-binding basic domain signature *
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Recent  studies  (reviewed in [1,2]) have  allowed  the characterization of  a
family of  eukaryotic transcription  factors  that bind DNA at   the consensus
sequence 5'-TGA(C/G)TCA-3'.  Proteins  known  to belong  to  this  family  are
listed below (references are only provided for recently determined sequences).

 - Yeast GCN4 transcription factor, a component of  the general control system
   that  regulates  the  expression of  amino  acid-synthesizing   enzymes  in
   response to amino acid  starvation, and the related Neurospora crassa cpc-1
   protein.
 - Neurospora crassa cys-3 which turns on  the expression  of structural genes
   which encode sulfur-catabolic enzymes [3].
 - Transcription factor AP-1, which binds  selectively to enhancer elements in
   the cis control regions of SV40 and metallothionein IIA.   AP-1, also known
   as c-jun, is  the  cellular  homolog  of the avian sarcoma virus 17 (ASV17)
   oncogene v-jun.
 - jun-B and jun-D,  probable transcription factors which  are  highly similar
   to jun/AP-1.
 - Epstein-Barr virus trans-activator protein BZLF1 [4].
 - Maize Opaque 2 [5], a  trans-acting transcriptional  activator  involved in
   the regulation of the production of zein proteins during endosperm.
 - The fos protein, a  proto-oncogene  that  forms  a  non-covalent dimer with
   c-jun.
 - The fos-related proteins fra-1, and fos B.

It has been shown [6] that there are  extensive similarities  between the DNA-
binding domain of GCN4, which is located in the C-terminal of the protein, and
the corresponding region of jun/AP1.     The region of highest similarity is a
domain of about 20 amino acid residues; about half of these residues are basic
(Arg or Lys).

In most of these protein this domain is located upstream of the leucine zipper
domain (see the relevant section).

-Consensus pattern: [RK](2)-x-[RKS]-N-x(2)-[STA](2)-x-[RK]-x-R-x-[RK]
-Sequences known to belong to this class detected by the pattern: ALL.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Note: the residue in position 4 is either Arg or Lys except in Opaque-2 where
 it is Ser.

-Last update: December 1991 / Text revised.

[ 1] Vogt P.K., Tjian R.
     Oncogene 3:3-7(1988).
[ 2] Curran T., Franza B.R. Jr.
     Cell 55:395-397(1988).
[ 3] Fu Y.-H., Marzluf G.A.
     J. Biol. Chem. 265:11942-11947(1990).
[ 4] Farrel P., Rowe D.T., Rooney C.M., Kouzarides T.
     EMBO J. 8:127-132(1989).
[ 5] Hartings H., Maddaloni M., Lazzaroni N., Di Fonzo N., Motto M.,
     Salamini F., Thompson R.D.
     EMBO J. 8:2795-2801(1989).
[ 6] Vogt P.K., Bos T.J., Doolittle R.F.
     Proc. Natl. Acad. Sci. U.S.A. 84:3316-3319(1987).