Disease relevance of IPP

• The MIPP-encoded protein is composed of four 48-amino acid repeat units and shares homology with a vaccinia virus gene product [1].
• [reaction: see text] Type II isopentenyl diphosphate:dimethylallyl diphosphate (IPP:DMAPP) isomerase from Synechocystis PCC 6803 catalyzes the interconversion of IPP and DMAPP [2].
• A solution of 0.1 M inosine, 0.1 M pyruvate, and 0.066 M phosphate (IPP) in a dosage of 7.5 ml per kologram of body weight prevented the 2,3-DPG decrease: prebypass, 15.74; postbypass, 14.85 [3].
• These findings suggest that some IgM antibodies against the VZV gene 22 protein produced in the early phase of VZV infection are cross-reactive with the HTLV-1 gag p19 protein because they recognize an antigenic determinant containing an IPPP tetrapeptide [4].

High impact information on IPP

• However, the effect of PAM-activated gammadelta T cells, but not that of IPP-activated cells, required cell-to-cell contact [5].
• MIPP protein binds to microfilaments in vitro and co-immunoprecipitates with actin [6].
• MIPP co-localized with concanavalin A at the endoplasmic reticulum, suggesting that MIPP might mediate interactions between microtubules and actin filaments [6].
• Our results suggest that MIPP could contribute to malignant progression in the mouse mammary epithelial cells by perverting their response to cues from the extracellular matrix [6].
• Although MIPP had little effect on the growth rate of human breast cell lines following transfection, it greatly reduced the formation of duct-like structures on reconstituted basement membrane [6].

Biological context of IPP

• The IPP gene is assigned to human chromosome 1p32-1p22 [7].
• Restriction mapping and Southern blot analysis show that IPP comprises eight exons spanning more than 47kb of genomic DNA [8].
• The IPP cDNA clone contains a 1752bp open reading frame that predicts a 584 amino-acid, 66kDa protein [8].
• Comparison of the TIM-IPP and the TIM-PGH structures with other liganded and unliganded structures also highlights the conformational flexibility of the ligand and the active site, as well as the conserved mode of ligand binding [9].
• MIPP-related sequences were also detected in higher eukaryotic genomes including human [1].

Anatomical context of IPP

• Expression in the visceral yolk sac was confined to the visceral endoderm cell layer suggesting that the MIPP gene is specifically expressed in tissues derived from the trophectoderm and primitive endoderm cell lineages [10].
• The expression of IAP genes paralleled that of MIPP in all tissues studied except for the presence of IAP transcripts in the amnion [10].
• PURPOSE: The ease of the transscrotal approach for penile prosthesis implantation and the proximity of the urethra has allowed the evolution of a new strategy for dual implantation of an AUS and IPP at a single setting [11].
• The method of providing for myocardial oxygen requirements during bypass was not standardized, and therefore the protective effect of IPP against ischemic damage in patients undergoing aortic valve replacement or myocardial revascularization could not be evaluated [3].
• The affinities of adult-type hemoglobins of green (Chelonia mydas) and loggerhead (Caretta caretta) sea turtles were determined at 25.7 degrees C as a function of pH, PCO2 and each of the organic phosphates found in erythrocytes of these species (ATP, IHP (substitute for IPP) and DPG) [12].

Associations of IPP with chemical compounds

• Cosedimentation assays performed with these domains expressed as glutathione S-transferase fusion proteins demonstrate an actin-binding activity mediated specifically by the kelch repeat domain of IPP [8].
• Comparison of the mode of binding of IPP and the transition state analogue phosphoglycolohydroxamate (PGH) suggests that the Glu167 side chain, as well as the triose part of the substrate, adopt different conformations as the catalysed reaction proceeds [9].
• IPP is an analogue of the substrate D-glyceraldehyde-3-phosphate, and it is observed to bind with its aldehyde oxygen in an oxyanion hole formed by ND2 of Asn11 and NE2 of His95 [9].
• The crystal structure of leishmania triosephosphate isomerase (TIM) complexed with 2-(N-formyl-N-hydroxy)-aminoethyl phosphonate (IPP) highlights the importance of Asn11 for binding and catalysis [9].
• When [14C]isopentenyl pyrophosphate (IPP) was used as the substrate for phytoene synthase a reduction (e.g. r,r mutant, 5-fold) in the formation of phytoene was observed with an accumulation (e.g. r,r mutant, 2-fold) of the immediate precursor geranylgeranyl pyrophosphate (GGPP) [13].

Analytical, diagnostic and therapeutic context of IPP

• Sequence analysis of the 5' region of a genomic clone revealed the presence of a solo IAP LTR with the same U5 duplication, and primer extension analysis confirmed that transcription of the MIPP gene is under the control of the IAP LTR [1].
• MATERIALS AND METHODS: We performed a multi-institutional, retrospective analysis in patients with 2 urological prostheses (AUS and IPP) [11].
• PCR studies conducted in 14 cases (2 cases of MF, 6 cases of drug-related APP, and 6 cases of IPP) revealed clonality in 2 cases of drug-related APP and 2 cases of IPP; the 2 studied MF-related cases did nor show clonal restriction [14].

References