Homology domains

Ferguson, K.M., et al. Structure of the high affinity complex of inositol triphosphate with a phospholipase C pleckstrin homology domain. Celt 83 1037-1046, 1995. 

Molecular characteristics of luciferase. A molecule of the luciferase of G. polyedra comprises three homologous domains (Li et al., 1997 Li and Hastings, 1998). The full-length luciferase (135 kDa) and each of the individual domains are most active at pH 6.3, and they show very little activity at pH 8.0. Morishita et al. (2002) prepared a recombinant Pyrocystis lunula luciferase consisting of mainly the third domain. This recombinant enzyme catalyzed the light emission of luciferin (luminescence A.max 474 nm) and the enzyme was active at pH 8.0. The recombinant enzyme of the third domain of G. polyedra luciferase was crystallized and its X-ray structure was determined (Schultz et al., 2005). A -barrel pocket putatively for substrate binding and catalysis was identified in the structure, and... 

Rel homology domain (RHD) that encompasses a sequence-specific DNA-binding domain, a dimerization domain and a nuclear translocation signal (NLS) (Fig. la). RelA, cRel, and RelB contain a transcription activation domain (TAD). NF-kB 1 and NF-kB2 are synthesized as large precursors, pi 05 and pi 00, that are posttranslationnally processed to generate the mature forms, p50 and p52, which lack a TAD. 

All PLC isozymes have conserved catalytic domains designated X and Y, and a C2 domain similar to that in cPLA2 (Fig. 2). In addition, the (3, y and 8 isozymes have pleckstrin homology (PH) domains and EF-hand domains located in theN-teiminal region. The y isozymes differ in that they have Src homology domains (SH2 and SH3) and an additional PH domain split by the SH domains. The (3 and y isozymes are of140-155 kDa mass, whereas the 8 isozymes are smaller (85 kDa) and the o isozyme is larger (240 kDa). 

Pleckstrin homology domain (PH-domain) was first identified at the amino and carboxyl termini of a haematopoietic protein called pleckstrin. PH-domain, a protein region of approximately 120 amino acids, by binding to phosphatidylinositol lipids of the biological membranes induces the translocation of the PH-domain containing protein to membrane compartment. Various PH-domains possess specificities for phosphoinositides phosphorylated at different sites within the inositol ring. 

The Rel homology domain (RHD) is an evolutionarily conserved domain found in some eukaryotic transcription factors, including NF-kB, the nuclear factors of activated T-cells (NFATs) and the drosophila proteins Dif and Relish. Some of these transcription factors form... 

Family of transcription factors that modulate the expression of genes which control immune, inflammatory, and acute-phase responses, as well as cell growth, responses to stress, apoptosis, and oncogenesis. All members of this family have a Rel-homology domain that contains sequences responsible for dimerization and DNA binding. In vertebrates, this family includes NF-kB1 (also known as p50), NF-kB2 (also known as p52), Rel (also known as cRel), Rel-A (also known as p65), and Rel-B. 

Essential for induction ofthe/Z-5 gene in inflammatory reactions is the binding site for nuclear factor kappa B (NF-kB). NF-kB responds to cytokines, stress, free radicals, ultraviolet irradiation, and bacterial, viral, or even parasitic antigens [2]. NF-kB stands for a family of subunits, which form homo-, and heterodimers. All NF-kB proteins share a highly conserved DNA-binding/dimerization domain called the Rel homology domain (RHD) consisting of two (3-strand core domains... 

PH Pleckstrin homology domain Binding to membrane phospholipids, such as phosphoinositides... 

TH Tec homology domain SH3-binding prolin-rich sequences and Znz+-binding motif... 

Platinum Complexes Pleckstrin Homology Domain Plexins PMF... 

Fig. 1. Structure of class I and class II PI3Ks and their substrate specificity. PRR, proline-rich regions PX, phox homology domain.

Src and PTB Homology Domains and the Formation of Receptor Signaling Complexes... 

The IFN-y receptor (the type II receptor) displays a more limited cellular distribution than that of the type I receptors (Table 8.5). This receptor is a transmembrane glycoprotein of molecular mass 50 kDa, which appears to function as a homodimer. The extracellular IFN-y binding region consists of approximately 200 amino acid residues folded into two homologous domains. Initiation of signal transduction also requires the presence of a second transmembrane glycoprotein known as AF-1 (accessory factor 1), which associates with the extracellular region of the receptor. 

Lietzke, S. E., Bose, S., Cronin, T. et al. Structural basis of 3-phosphoinositide recognition by pleckstrin homology domains. Mol. Cell 6 385-394,2000. 

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