The second LIM domain of the paxillin like protein family
The second LIM domain of the paxillin like protein family: This family consists of paxillin, leupaxin, Hic-5 (ARA55), and other related proteins. There are four LIM domains in the C-terminal of the proteins and leucine-rich LD-motifs in the N-terminal region. Members of this family are adaptor proteins to recruit key components of signal-transduction machinery to specific sub-cellular locations. Paxillin is found at the interface between the plasma membrane and the actin cytoskeleton. Paxillin serves as a platform for the recruitment of numerous regulatory and structural proteins that together control the dynamic changes in cell adhesion, cytoskeletal reorganization and gene expression that are necessary for cell migration and survival. Leupaxin is a cytoskeleton adaptor protein, which is preferentially expressed in hematopoietic cells. It associates with focal adhesion kinases PYK2 and pp125FAK and identified to be a component of the osteoclast pososomal signaling complex. Hic-5 controls cell proliferation, migration and senescence by functioning as coactivator for steroid receptors such as androgen receptor, glucocorticoid receptor and progesterone receptor. LIM domains are 50-60 amino acids in size and share 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 complexes.
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.
Jiyao W et al.(2023). "The conserved domain database in 2023.",