The Experts below are selected from a list of 843 Experts worldwide ranked by ideXlab platform
Rossella Miele - One of the best experts on this subject based on the ideXlab platform.
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analysis of role of aromatic residues in extracellular loop 2 of Prokineticin Receptor 2 in ligand binding probed with genetically encoded photo crosslinkers
Biochimica et Biophysica Acta, 2021Co-Authors: Maria Rosaria Fullone, Roberta Lattanzi, Daniela Maftei, Maria Carmela Bonaccorsi, Rossella MieleAbstract:Prokineticin 2 (PK2) and Prokineticin 2 beta (PK2β), products of alternative splicing of pk2 gene, are chemokine-like proteins. While PK2 mediates its biological activities by signaling with the same efficiency through two homologous G protein coupled Receptors, Prokineticin Receptor 1 (PKR1) and Prokineticin Receptor 2 (PKR2), PK2β is able to bind specifically PKR1. Extracellular loop 2 (ECL2) of chemokine Receptors is a part of a transmembrane (TM) ligand binding site. In the ECL2 of PKR2 is present, as well as in all chemokine Receptors, an aromatic residue cluster, involving tryptophan 212 localized four residues after an ECL2 conserved cysteine, and Phenylalanine 198 located in the top of TM 4. In this work, the photoactivatable unnatural amino acid p-benzoyl-L-phenylalanine is incorporated by amber codon suppression technology into PKR2 in position 212. Experiments of photoactivatable cross-linking demonstrated the role of tryptophan in position 212 for binding the ligand contacting Tryptophan in position 24. We also analyzed the role of Phenylalanine 198 in the specificity of PKRs binding. The comparison of TM-bundle binding sites between PKR1 and PKR2 revealed that they are completely conserved except for one residue: valine 207 in human PKR1, which is phenylalanine 198 in human PKR2. The F198V mutation in PKR2 permits to obtain a Receptor able to bind more efficiently PK2β, a ligand highly specific for PKR1.
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trypanosoma cruzi trans sialidase induces stat3 and erk activation by Prokineticin Receptor 2 binding
Cell Biochemistry and Function, 2021Co-Authors: Roberta Lattanzi, Daniela Maftei, Maria Rosaria Fullone, Rossella MieleAbstract:Tc85, as other members of trans-sialidase family, is involved in Trypanosoma cruzi parasite adhesion to mammalian cells. Particularly, Tc85 acts through specific interactions with Prokineticin Receptor 2, a G-protein coupled Receptor involved in diverse physiological and pathological processes. In this manuscript, through biochemical analyses, we demonstrated that LamG, a Tc85 domain, physically interacts with the Prokineticin Receptor 2. Moreover, expressing Prokineticin Receptor 1 and 2 we demonstrated that LamG specifically activates Prokineticin Receptor 2 through a strong coupling with Gαi or Gαq proteins in yeast strains and inducing ERK and NFAT phosphorylation in CHO mammalian cells. To demonstrate a Tc85 physiological role in T. cruzi infection of the nervous system, we evidenced a strong STAT3 and ERK activation by LamG in mice Dorsal Root Ganglia. L173R is the most common Prokineticin Receptor 2 mutation reported in Kallmann syndrome and it is a founder mutation. Our results demonstrated that in cells co-expressing Prokineticin Receptor 2 mutant (L173R) and wild-type, LamG is unable to induce signal transduction. The L173R mutation in heterozygosity may allow for a selective advantage due to increased protection from T. cruzi infection. SIGNIFICANCE OF THE STUDY: The Chagas' disease affecting millions of people worldwide is caused by an eukaryotic microorganism called T. cruzi. Pharmacological treatment for patients with Chagas' disease is still limited. Indeed, the small number of drugs available shows important side effects that can be debilitating for patient health. In order to replicate and produce new parasites T. cruzi uses a complex of different proteins produced by both the parasite and the human host cells. So, understanding the molecular details used by T. cruzi to be internalised by different types of human cells is an important step towards the development of new drugs for this disease. Prokineticin Receptors are relevant for host-parasite interaction. To characterise the signal transduction cascade induced by their activation may help to understand the molecular details of cell infection, leading to novel therapeutic alternative for this debilitating disease.
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Evidence that Prokineticin Receptor 2 exists as a dimer in vivo
Cellular and Molecular Life Sciences, 2011Co-Authors: Sara Marsango, Maria Carmela Bonaccorsi Di Patti, Donatella Barra, Rossella MieleAbstract:Prokineticins are proteins that regulate diverse biological processes including gastrointestinal motility, angiogenesis, circadian rhythm, and innate immune response. Prokineticins bind two closed related G-protein coupled Receptors (GPCRs), PKR1 and PKR2. In general, these Receptors act as molecular switches to relay activation to heterotrimeric G-proteins and a growing body of evidence points to the fact that GPCRs exist as homo- or heterodimers. We show here by Western-blot analysis that PKR2 has a dimeric structure in neutrophils. By heterologous expression of PKR2 in Saccharomyces cerevisiae , we examined the mechanisms of intermolecular interaction of PKR2 dimerization. The potential involvement of three types of mechanisms was investigated: coiled-coil, disulfide bridges, and hydrophobic interactions between transmembrane domains. Characterization of differently deleted or site-directed PKR2 mutants suggests that dimerization proceeds through interactions between transmembrane domains. We demonstrate that co-expressing binding-deficient and signaling-deficient forms of PKR2 can re-establish Receptor functionality, possibly through a domain-swapping mechanism.
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erratum to evidence that Prokineticin Receptor 2 exists as a dimer in vivo
Cellular and Molecular Life Sciences, 2011Co-Authors: Sara Marsango, Donatella Barra, Maria Carmela Bonaccorsi Di Patti, Rossella MieleAbstract:Erratum to: Cell Mol Life SciDOI 10.1007/s00018-010-0601-6It has come to our attention that proper attribution wasmissing for one of the figures:Figure 1 is a modified version of the topology of PKR2Receptor taken from Abreu AP, Kaiser UB, Latronico AC(2010) The role of Prokineticins in the pathogenesisof hypogonadotropic hypogonadism. Neuroendocrinology91:283–290.
Paolin Kuo - One of the best experts on this subject based on the ideXlab platform.
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polymorphisms of endocrine gland derived vascular endothelial growth factor gene and its Receptor genes are associated with recurrent pregnancy loss
Human Reproduction, 2010Co-Authors: Sheng Hsiang Lin, Yichi Chen, Iwen Lee, Chaochin Hsu, Hsienan Pan, Paolin KuoAbstract:background: Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) and its Receptor genes [Prokineticin Receptor 1 (PKR1) and Prokineticin Receptor 2 (PKR2)] have been identified in the last decade and their expression is restricted to the steroidogenic glands (ovary, testis, adrenal gland and placenta). Their expression patterns also suggest a close relationship to early pregnancy. However, little information is available regarding the role of EG-VEGF and its Receptors (PKR1 and PKR2) in recurrent pregnancy loss (RPL). This study was conducted to investigate the association between polymorphisms of EG-VEGF and its Receptor genes (PKR1 and PKR2) and idiopathic RPL. methods: In this case–control study, 115 women with a history of idiopathic RPL and 170 controls were included. A total of 11 tag single nucleotide polymorphisms (SNPs) selected from EG-VEGF, PKR1 and PKR2 were genotyped. We further used multifactor dimensionality reduction (MDR) analysis to choose a best model and evaluate gene–gene interactions. results: Two tag SNPs of PKR1 (rs4627609, rs6731838) and one tag SNP of PKR2 (rs6053283) were significantly associated with idiopathic RPL (P , 0.05). The frequencies of haplotypes C-G and T-A of PKR1 and haplotype A-G-C-G-G of PKR2 were significantly increased in women with idiopathic RPL (P , 0.05); MDR tests revealed gene– gene interactions between three loci [EG-VEGF (rs7513898), PKR1(rs6731838), PKR2(rs6053283)] based on the association model (P ¼ 0.008). The adjusted odds ratio of high- and low-risk genotype combinations in the three-locus model was 3.94 (95% confidence interval: 2.38 –6.52). conclusions: EG-VEGF Receptor (PKR1, PKR2) gene polymorphisms and haplotypes were associated with idiopathic RPL. These three genes (EG-VEGF, PKR1 and PRK2) jointly contribute to RPL in the Taiwanese Han population.
Akio Yamaguchi - One of the best experts on this subject based on the ideXlab platform.
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endocrine gland derived vascular endothelial growth factor strengthens cell invasion ability via Prokineticin Receptor 2 in colon cancer cell lines
Oncology Reports, 2013Co-Authors: Shinsuke Tabata, Takanori Goi, Toshiyuki Nakazawa, Youhei Kimura, Kanji Katayama, Akio YamaguchiAbstract:Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) has recently been identified as one of the vascular endothelial growth factors, and it is considered that the overexpression of EG-VEGF in colon cancer is related to hepatic metastasis. In this study, we report our recent novel findings of the involvement of EG-VEGF in cell invasion of colon cancer cells. Colon cancer cell lines (DLD-1 and HCT116) with high expression of Prokineticin Receptor (PK-R) 1 and 2 were stimulated with the EG-VEGF protein. Furthermore, Matrigel cell invasion assay was performed to examine the changes in cancer cell invasion. In addition, we investigated the mRNA expression of matrix metalloproteinase (MMP)-2, -7 and -9 in cancer cells. Finally, the EG-VEGF Receptor on the colon cancer cell membrane was blocked by anti-PK-R1 and -PK-R2 antibodies to study whether cell invasion ability would be altered. In colon cancer cell lines where the expression of PK-R1 and 2 was confirmed, stimulation with EG-VEGF increased cell invasion a maximum of ~3-5 times. Furthermore, an increase in the mRNA and protein expression of MMP-2, -7 and -9 was observed. We also observed that the cell invasion rate decreased only after exposure to the anti-PK-R2 antibody. The study showed that the EG-VEGF protein may act on MMP-2, -7 and -9 via PK-R2 to strengthen cell invasion ability in colon cancer cell lines.
Sheng Hsiang Lin - One of the best experts on this subject based on the ideXlab platform.
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polymorphisms of endocrine gland derived vascular endothelial growth factor gene and its Receptor genes are associated with recurrent pregnancy loss
Human Reproduction, 2010Co-Authors: Sheng Hsiang Lin, Yichi Chen, Iwen Lee, Chaochin Hsu, Hsienan Pan, Paolin KuoAbstract:background: Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) and its Receptor genes [Prokineticin Receptor 1 (PKR1) and Prokineticin Receptor 2 (PKR2)] have been identified in the last decade and their expression is restricted to the steroidogenic glands (ovary, testis, adrenal gland and placenta). Their expression patterns also suggest a close relationship to early pregnancy. However, little information is available regarding the role of EG-VEGF and its Receptors (PKR1 and PKR2) in recurrent pregnancy loss (RPL). This study was conducted to investigate the association between polymorphisms of EG-VEGF and its Receptor genes (PKR1 and PKR2) and idiopathic RPL. methods: In this case–control study, 115 women with a history of idiopathic RPL and 170 controls were included. A total of 11 tag single nucleotide polymorphisms (SNPs) selected from EG-VEGF, PKR1 and PKR2 were genotyped. We further used multifactor dimensionality reduction (MDR) analysis to choose a best model and evaluate gene–gene interactions. results: Two tag SNPs of PKR1 (rs4627609, rs6731838) and one tag SNP of PKR2 (rs6053283) were significantly associated with idiopathic RPL (P , 0.05). The frequencies of haplotypes C-G and T-A of PKR1 and haplotype A-G-C-G-G of PKR2 were significantly increased in women with idiopathic RPL (P , 0.05); MDR tests revealed gene– gene interactions between three loci [EG-VEGF (rs7513898), PKR1(rs6731838), PKR2(rs6053283)] based on the association model (P ¼ 0.008). The adjusted odds ratio of high- and low-risk genotype combinations in the three-locus model was 3.94 (95% confidence interval: 2.38 –6.52). conclusions: EG-VEGF Receptor (PKR1, PKR2) gene polymorphisms and haplotypes were associated with idiopathic RPL. These three genes (EG-VEGF, PKR1 and PRK2) jointly contribute to RPL in the Taiwanese Han population.
Hideaki Masuzaki - One of the best experts on this subject based on the ideXlab platform.
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a case of kallmann syndrome carrying a missense mutation in alternatively spliced exon 8a encoding the immunoglobulin like domain iiib of fibroblast growth factor Receptor 1
Human Reproduction, 2010Co-Authors: Kiyonori Miura, Stephanie B Seminara, Shoko Miura, Kohichiro Yoshiura, Daisuke Hamaguchi, Norio Niikawa, Hideaki MasuzakiAbstract:Fibroblast growth factor Receptor 1 (FGFR1) is one of the causative genes for Kallmann syndrome (KS), which is characterized by isolated hypogonadotropic hypogonadism with anosmia/hyposmia. The third immunoglobulin-like domain (D3) of FGFR1 has the isoforms FGFR1-IIIb and FGFR1-IIIc, which are generated by alternative splicing of exons 8A and 8B, respectively. To date, the only mutations to have been identified in D3 of FGFR1 are in exon 8B. We performed mutation analysis of FGFR1 in a 23-year-old female patient with KS and found a missense mutation (c.1072C>T) in exon 8A of FGFR1. The c.1072C>T mutation was not detected in her family members or in 220 normal Japanese and 100 Caucasian female controls. No mutation in other KS genes, KS 1, Prokineticin-2, Prokineticin Receptor-2 and FGF-8 was detected in the affected patient or in her family members. Therefore, this is the first case of KS carrying a de novo missense mutation in FGFR1 exon 8A, suggesting that isoform FGFR1-IIIb, as well as isoform FGFR1-IIIc, plays a crucial role in the pathogenesis of KS.
