The second LIM domain of lipoma preferred partner (LPP)
The second LIM domain of lipoma preferred partner (LPP): LPP is a member of the zyxin LIM protein family and contains three LIM zinc-binding domains at the C-terminal and proline-rich region at the N-terminal. LPP initially identified as the most frequent translocation partner of HMGA2 (High Mobility Group A2) in a subgroup of benign tumors of adipose tissue (lipomas). It was also shown to be rearranged in a number of other soft tissues, as well as in a case of acute monoblastic leukemia. In addition to its involvement in tumors, LPP was inedited as a smooth muscle restricted LIM protein that plays an important role in SMC migration. LPP is localized at sites of cell adhesion, cell-cell contacts and transiently in the nucleus. In nucleus, it acts as a coactivator for the ETS domain transcription factor PEA3. In addition to PEA3, it interacts with alpha-actinin,vasodilator stimulated phosphoprotein (VASP),Palladin, and Scrib. The LIM domains are the main focal adhesion targeting elements and that the proline- rich region, which harbors binding sites for alpha-actinin and vasodilator- stimulated phosphoprotein (VASP), has a weak targeting capacity. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.
Comment:The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. The Zn binding residues of LIM domain are highly conserved.