Information about Zif268

Cartoon representation of Zif268 (blue) containing three zinc fingers in complex with DNA (orange). The coordinating amino acid residues of the middle zinc ion (green) are highlighted.
early growth response 1
Identifiers
Symbol	EGR1
Entrez	1958
HUGO	3238
OMIM	128990
RefSeq	NM_001964
UniProt	P18146
Other data
Locus	Chr. 5 q31.1

Zif268 is a mammalian transcription factor that is now officially known as Egr1 (Early Growth Response Protein 1). It was also named Krox-24, NGFI-A, TIS8, and ZENK. It was originally discovered in mouse.

Structure

The DNA binding domain of Zif268 consists of three zinc finger domains of the Cys₂His₂ type. The amino acid structure of the Zif268 zinc finger domain is given in this table, using the single letter amino acid code. The fingers 1 to 3 are indicated by f1 - f3. The numbers are in reference to the residues (amino acids) of alpha helix (there is no '0'). The residues marked 'x' are not part of the zinc fingers, but rather serve to connect them all together.

-1

1

2

3

4

5

6

7

8

9

x

x

x

x

x

f1

M

A

E

E

R

P

Y

A

C

P

V

E

S

C

D

R

R

F

S

R

S

D

E

L

T

R

H

I

R

I

H

T

G

Q

K

P

f2

F

O

C

A

I

?

?

C

M

R

N

F

S

R

S

D

H

L

T

T

H

I

A

T

H

T

G

E

K

P | f3 || || || || || || || F || A || C || D || I || ? || ? || C || G || R || K || F || A || R || S || D || E || R || K || R || H || T || K || I || H || L || R || Q || K || D |

The crystal structure of DNA bound by the zinc finger domain of Zif268 was solved in 1991, which greatly aided early research in zinc finger DNA-binding domains.^[1]

The human Zif268/EGR1 protein contains (in its unprocessed form) 543 amino acids with a molecular weight of 57.5 kDa, and the gene is located on the chromosome 5.

Function

Zif268 binds the DNA sequence 5'-GC[G/T]GGGCG-3.^[2][3]

It has a distinct pattern of expression in the brain, and its induction has been shown to be assiociated with neuronal activity. Several studies suggest it has a role in neuronal plasticity.^[4]

Zif268 has also been found to regulate the expression of synaptobrevin II (a protein important for synaptic exocytosis).^[5]

References

External links

• MeSH Zif+268+protein,+human

•  • [ e] Transcription factors and intracellular receptors
General transcription factors	TFIIA, TFIIB, TFIID, TFIIE, TFIIF, TFIIH
Basic-helix-loop-helix	AhR - BMAL-CLOCK - E2F - HIF - Myc - Pax (PAX3, PAX6) - Twist - Myogenic regulatory factors (MyoD, Myogenin, MYF5, MYF6)
Basic leucine zipper	C/EBP - CREB - AP-1 (c-Fos, c-Jun) - Activating transcription factor
Basic helix-loop-helix leucine zipper	MITF - SREBP
Nuclear receptors	subfamily 1 (Thyroid hormone, CAR, FXR, LXR, PPAR, PXR, RAR, ROR, Rev-ErbA, VDR) - subfamily 2 (COUP-TF, Ear-2, HNF4, PNR, RXR, Testicular receptor, TLX) - subfamily 3/Steroid hormone (Estrogen, Estrogen related, Glucocorticoid, Mineralocorticoid, Progesterone, Androgen) - subfamily 4 (NGFIB, NURR1, NOR1) - subfamily 5 (SF1, LRH-1) - subfamily 6 (GCNF) - subfamily 0 (DAX1, SHP)
Winged-helix transcription factors	FOX proteins (FOXP2, FOXP3)
Zinc finger/protein	Gli1 - Gli2 - Gli3 - KlF (Sp1) - Zbtb7 - Zif268
Other families	CAP - CBF (RUNX1, RUNX2) - GATA (GATA1) - NANOG - NF-kB - Rho/Sigma - R-SMAD - Sox2 - POU domain (PIT-1, BRN-3, Octamer transcription factor: 2, 4) - STAT (1, 2, 3, 4, 5, 6)