The second LIM domain of Cysteine Rich Protein 3 (CRP3/MLP)
The second LIM domain of Cysteine Rich Protein 3 (CRP3/MLP): Cysteine-rich proteins (CRPs) are characterized by the presence of two LIM domains linked to short glycine-rich repeats (GRRs). The CRP family members include CRP1, CRP2, CRP3/MLP and TLPCRP1, CRP2 and CRP3 share a conserved nuclear targeting signal (K/R-K/R-Y-G-P-K), which supports the fact that these proteins function not only in the cytoplasm but also in the nucleus. CRPs control regulatory pathways during cellular differentiation, and involve in complex transcription circuits, and the organization as well as the arrangement of the myofibrillar/cytoskeletal network.CRP3 also called Muscle LIM Protein (MLP), which is a striated muscle-specific factor that enhances myogenic differentiation. The second LIM domain of CRP3/MLP interacts with cytoskeletal protein beta-spectrin. CRP3/MLP also interacts with the basic helix-loop-helix myogenic transcription factors MyoD, myogenin, and MRF4 thereby increasing their affinity for specific DNA regulatory elements. 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.",