home *** CD-ROM | disk | FTP | other *** search
- ************************
- * LIM domain signature *
- ************************
-
- Recently [1,2] a number of proteins have been found to contain a conserved
- cysteine-rich domain of about 60 amino-acid residues. These proteins are:
-
- - Caenorhabditis elegans mec-3; a protein required for the differentiation of
- the set of six touch receptor neurons in this nematode.
- - Caenorhabditis elegans lin-11; a protein required for the asymmetric
- division of vulval blast cells.
- - Mammalian insulin gene enhancer binding protein Isl-1. Isl-1 binds to one
- of the two cis-acting protein-binding domains of the insulin gene.
- - Hamster lmx-1, which acts as a transcriptional activator by binding to the
- FLAT element; a beta-cell-specific transcriptional enhancer found in the
- insulin gene.
- - Rat LH-2, a transcriptional regulatory protein involved in the control of
- cell differentiation in developing lymphoid and neural cell types.
- - Drosophila protein apterous, required for the normal development of the
- wing and halter imaginal discs.
- - Xenopus Xlim-1, probably involved in the establishment of the body plan
- during gastrulation in embryos.
- - Xenopus Xlim-3, probably involved in the specification and maintenance of
- differentiation of distinct neuronal and neuroendocrine tissues.
- - Mammalian rhombotins. Rhombotin 1 (TTG-1) and rhombotin-2 (TTG-2) are
- proteins of about 160 amino acids whose genes are disrupted by chromosomal
- translocations in T-cell leukemia.
- - Human and avian cysteine-rich protein (CRP), a 192 amino-acid protein of
- unknown function. Seems to interact with zyxin.
- - Mammalian cysteine-rich intestinal protein (CRIP), a small protein which
- seems to have a role in zinc absorption and may function as an
- intracellular zinc transport protein.
- - Sunflower pollen specific protein SF3.
- - Chicken zyxin [3]. Zyxin is a low-abundance adhesion plaque protein which
- has been shown to interact with CRP.
- - Yeast protein LRG1 which is involved in sporulation [4].
- - Yeast hypothetical protein YKR090w.
-
- These proteins generally have two tandem copies of a domain, called LIM (for
- Lin-11 Isl-1 Mec-3) in their N-terminal section. Zyxin is an exception in that
- it contains three domains located at the C-terminal extremity. In apterous,
- Isl-1, LH-2, lin-11, Xlim-1, Xlim-3, lmx-1 and mec-3 there is a homeobox
- domain some 50 to 95 amino acids after the LIM domains.
-
- In the LIM domain, there are seven conserved cysteine residues and a
- histidine. The arrangement followed by these conserved residues is C-x(2)-C-
- x(16,23)-H-x(2)-C-x(2)-C-x(2)-C-x(16,21)-C-x(2,3)-[CHD]. The LIM domain binds
- two zinc ions [5]. LIM does not bind DNA, rather it seems to act as interface
- for protein-protein interaction. We developed a pattern that spans the first
- half of the LIM domain.
-
- -Consensus pattern: C-x(2)-C-x(15,21)-[FYWH]-H-x(2)-C-x(2)-C-x(2)-C-x(3)-
- [LIVMF]
- [The 5 C's and the H bind zinc]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: June 1994 / Pattern and text revised.
-
- [ 1] Freyd G., Kim S.K., Horvitz H.R.
- Nature 344:876-879(1990).
- [ 2] Baltz R., Evrard J.-L., Domon C., Steinmetz A.
- Plant Cell 4:1465-1466(1992).
- [ 3] Sadler I., Crawford A.W., Michelsen J.W., Beckerle M.C.
- J. Cell Biol. 119:1573-1587(1992).
- [ 4] Mueller A., Xu G., Wells R., Hollenberg C.P., Piepersberg W.
- EMBL/GenBank: X78453.
- [ 5] Michelsen J.W., Schmeichel K.L., Beckerle M.C., Winge D.R.
- Proc. Natl. Acad. Sci. U.S.A. 90:4404-4408(1993).
-