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Wijnand P. M. Geraerts - One of the best experts on this subject based on the ideXlab platform.

  • Expression and characterization of molluscan Insulin-Related Peptide VII from the molluscLymnaea stagnalis
    Neuroscience, 1996
    Co-Authors: A.b. Smit, Sabine Spijker, J. Van Minnen, Julian F. Burke, F. De Winter, R. Van Elk, Wijnand P. M. Geraerts
    Abstract:

    A complementary DNA clone encoding molluscan Insulin-Related Peptide VII was identified from a complementary DNA library of the cerebral ganglia of the CNS of the freshwater snail, Lymnaea stagnalis. The novel molluscan Insulin-Related Peptide VII complementary DNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and an A and B chain, and is connected by an unusual long C Peptide. The A and B chains, as well as the C Peptide of molluscan Insulin-Related Peptide VII, differ remarkably in primary structure with the previously identified molluscan Insulin-Related Peptides. The C Peptide of molluscan Insulin-Related Peptide VII shares no significant sequence identity with counterparts in other molluscan Insulin-Related Peptides. Both molluscan Insulin-Related Peptide VII and the other molluscan Insulin-Related Peptides exhibit structural features which make them a unique class of the insulin superfamily. Molluscan Insulin-Related Peptide VII complementary DNA was shown to hybridize in situ with messenger RNA present in the cerebral light green cells, neuroendocrine cells that control growth and that have previously been shown to produce molluscan Insulin-Related Peptides I-III and V. Uniquely, the molluscan Insulin-Related Peptide VII gene is also expressed in neurons that may form part of the feeding circuitry in Lymnaea, indicating that it may function as a neurotransmitter/neuromodulator.

  • CHARACTERIZATION OF A PUTATIVE MOLLUSCAN Insulin-Related Peptide RECEPTOR
    Gene, 1995
    Co-Authors: Edwin Roovers, Wijnand P. M. Geraerts, M. E. Vincent, E. R. Van Kesteren, Rudi J. Planta, Erno Vreugdenhil, H. Van Heerikhuizen
    Abstract:

    In the pond snail Lymnaea stagnalis (Ls), growth and associated processes are likely to be controlled by a family of molluscan Insulin-Related Peptides (MIP). Here we report on the cloning of a cDNA encoding a putative receptor for these MIP. This cDNA was isolated from Ls via PCR with degenerate oligodeoxynucleotides corresponding to conserved parts of the tyrosine kinase domain of the human insulin receptor and its Drosophila homologue. Many of the typical insulin-receptor features, including a cysteine-rich domain, a single transmembrane domain and a tyrosine-kinase domain are conserved in the predicted, 1607-amino acid (aa) protein. Comparison of the aa sequence of the molluscan receptor to other insulin-receptor sequences revealed strong variations in the percentage of sequence identity for the different domains, ranging from 70% sequence identity in the tyrosine-kinase domain to virtually no sequence identity in the C-terminal sequence. Striking differences are the absence of a clear tetrabasic cleavage site, and the extremely long C-terminus of 308 aa that contains seven Tyr residues. Southern blot analyses at varying stringencies, extensive screening of cDNA- and genomic libraries, and PCR experiments indicate the presence of a single putative MIP receptor. This suggests that the four different MIP may exert their functional role in Ls by binding to the same receptor.

  • Evolutionary conservation of the insulin gene structure in invertebrates: cloning of the gene encoding molluscan Insulin-Related Peptide III from Lymnaea stagnalis
    Journal of molecular endocrinology, 1993
    Co-Authors: A.b. Smit, R. Van Elk, Harm Van Heerikhuizen, A. Van Marle, Jan Bogerd, Wijnand P. M. Geraerts
    Abstract:

    Although insulins and structurally related Peptides are found in vertebrates as well as in invertebrates, it is not clear whether the genes encoding these hormones have emerged from a single ancestral (insulin)-type of gene or, alternatively, have arisen independently through convergent evolution from different types of gene. To investigate this issue, we cloned the gene encoding the molluscan Insulin-Related Peptide III (MIP III) from the freshwater snail, Lymnaea stagnalis. The predicted MIP III preprohormone had the overall organization of preproinsulin, with a signal Peptide and A and B chains, connected by two putative C Peptides. Although MIP III was found to share key features with vertebrate insulins, it also had unique structural characteristics in common with the previously identified MIPs I and II, thus forming a distinct class of MIP Peptides within the insulin superfamily. MIP III is synthesized in neurones in the brain. It is encoded by a gene with the overall organization of the vertebrate insulin genes, with three exons and two introns, of which the second intron interrupts the coding region of the C Peptides. Our data therefore demonstrate that in the Archaemetazoa, the common ancestor of the vertebrates and invertebrates, a primordial Peptide with a two-chain insulin configuration encoded by a primordial insulin-type gene must have been present.

  • Isolation and chemical characterization of a novel Insulin-Related neuroPeptide from the freshwater snail, Lymnaea stagnalis.
    European journal of biochemistry, 1992
    Co-Authors: Wijnand P. M. Geraerts
    Abstract:

    A novel molluscan Insulin-Related Peptide (MIP) III, has been isolated from alcohol extracts of the neurohaemal area of the cerebral neuroendocrine light-green neurones of Lymnaea stagnalis. MIP III was purified by sequential high-performance gel-permeation chromatography followed by reverse-phase HPLC. MIP III is a heterodimer connected by disulphide bonds. Edman degradation analysis and subsequent alignment with the A and B chains of the previously identified MIP I and II showed that the 24-amino-acid Peptide with the sequence pQSRPSIVC(E)CCFNQCTVQ(E)LLAYC represents the MIP III A chain, and the 37-amino-acid Peptide sequence TTQHTCSILSRPHPRGLCGSTLANMVQWLCSTYTTSS the B chain. The overall amino acid sequence of MIP III shows about 50% similarity with those of MIP I and II, and only 20–40% similarity with other Peptides of the insulin superfamily. Important structural features, e.g. disulphide bridges and the hydrophobic core, are conserved in MIP III.

  • Characterization of a cDNA clone encoding molluscan Insulin-Related Peptide V of Lymnaea stagnalis.
    Brain research. Molecular brain research, 1992
    Co-Authors: A.b. Smit, Wijnand P. M. Geraerts, Irene Meester, Harm Van Heerikhuizen, Steven F. T. Thijsen, J. Joosse
    Abstract:

    A cDNA clone encoding molluscan Insulin-Related Peptide V (MIP V) was isolated from a cDNA library of the central nervous system (CNS) of the freshwater snail, Lymnaea stagnalis, using a heterologous screening with a previously identified MIP II cDNA. The MIP V cDNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and an A and B chain, however, in this case connected by two distinct C Peptide, C alpha and C beta, instead of one single C Peptide. This phenomenon, which is shared by the MIP II precursor, represents a new development in the prohormone organization of Peptides belonging to the insulin superfamily. The A and B chains of MIPs V, I and II, differ remarkably in primary structure; in contrast, the C alpha Peptide domains are almost identical. MIP V has only limited sequence similarity with insulins and related Peptides. Both MIP V and I exhibit structural features, which make them a unique class of the insulin superfamily. The MIP I, II and V genes are expressed in a single type of neuron: the growth controlling neuroendocrine light green cells of the Lymnaea CNS.

J. Joosse - One of the best experts on this subject based on the ideXlab platform.

  • Purification and sequencing of molluscan Insulin-Related Peptide I (MIP I) from the neuroendocrine light green cells of Lymnaea stagnalis
    Molecular and cellular endocrinology, 1992
    Co-Authors: Wijnand P. M. Geraerts, Rob H.m. Ebberink, J. Joosse
    Abstract:

    Abstract The body growth controlling cerebral neuroendocrine light green cells of the freshwater snail, Lymnaea stagnalis , express various members of a gene family encoding different though related prepromolluscan Insulin-Related Peptides. In the present study, molluscan Insulin-Related Peptide I (MIP I) together with the corresponding connecting Peptide, C α Peptide, have been isolated and structurally identified. MIP I is a heterodimer of A and B chains bonded by disulphide bridges. Two isoforms of MIP I could be discerned. Mass spectrometry revealed that of one form both the A and B chains have N-terminal pyroglutamyl residues, whereas of the other form only the B chain has such residues. After removal of the pyroglutamyl residues with pyroglutamate aminopeptidase, followed by disulphide bond cleavage and pyridylethylation of cysteine residues, the sequences of MIP I have been determined using Edman degradation as: A chain: (p)QGTTNlVCECCMKPCTLSELRQYCP B chain: pQPSACNINDRPHRRGVCGSALADLVDPACSSSNGPA. The C α Peptide has also been isolated and its sequence was determined as NAETDLDDPLRN1KLSSESALTYLY. These sequences are in agreement with those predicted by a cDNA sequence encoding preproMIP I, with the exception that the two C-terminal amino acids of the B chain are posttranslationally removed.

  • Characterization of a cDNA clone encoding molluscan Insulin-Related Peptide V of Lymnaea stagnalis.
    Brain research. Molecular brain research, 1992
    Co-Authors: A.b. Smit, Wijnand P. M. Geraerts, Irene Meester, Harm Van Heerikhuizen, Steven F. T. Thijsen, J. Joosse
    Abstract:

    A cDNA clone encoding molluscan Insulin-Related Peptide V (MIP V) was isolated from a cDNA library of the central nervous system (CNS) of the freshwater snail, Lymnaea stagnalis, using a heterologous screening with a previously identified MIP II cDNA. The MIP V cDNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and an A and B chain, however, in this case connected by two distinct C Peptide, C alpha and C beta, instead of one single C Peptide. This phenomenon, which is shared by the MIP II precursor, represents a new development in the prohormone organization of Peptides belonging to the insulin superfamily. The A and B chains of MIPs V, I and II, differ remarkably in primary structure; in contrast, the C alpha Peptide domains are almost identical. MIP V has only limited sequence similarity with insulins and related Peptides. Both MIP V and I exhibit structural features, which make them a unique class of the insulin superfamily. The MIP I, II and V genes are expressed in a single type of neuron: the growth controlling neuroendocrine light green cells of the Lymnaea CNS.

  • Purification and sequencing of molluscan Insulin-Related Peptide II from the neuroendocrine light green cells in Lymnaea stagnalis
    Endocrinology, 1992
    Co-Authors: Wijnand P. M. Geraerts, J. Joosse
    Abstract:

    The growth-controlling neuroendocrine light green cells of the freshwater snail, Lymnaea stagnalis, express a family of genes encoding structurally related, yet distinct, molluscan Insulin-Related Peptides (MIPs). In the present study one of these Peptides, MIP II, has been isolated and structurally identified. MIP II is a heterodimer of A and B chains connected by disulfide bonds. Both chains are N-terminally blocked with pyroglutamate. After cleaving of the A and B chains and deblocking with pyroglutamate amino-peptidase their sequences have been determined as: A chain: pQRTTNLVCECCFNYCTPDVVRKYCY and B chain: pQSSCSLSSRPHPRGICGSNLAGFRAFICSNQNSPS. In comparison with the MIP II sequence based on complementary DNA studies, it is clear that the two C-terminal amino acid residues of the B chain are posttranslationally removed. In addition, the glutamic acid residue in A chain was recovered in very low yields during Edman degradation, suggesting that the residue may be posttranslationally modified.

  • Characterization of a cDNA clone encoding molluscan insulin‐related Peptide II of Lymnaea stagnalis
    European journal of biochemistry, 1991
    Co-Authors: A.b. Smit, Wijnand P. M. Geraerts, Irene Meester, Harm Van Heerikhuizen, J. Joosse
    Abstract:

    A cDNA clone encoding molluscan Insulin-Related Peptide (MIP) II was isolated from a cDNA library of the central nervous system (CNS) of the freshwater snail, Lymnaea stagnalis, using a heterologous screening with a previously identified MIP cDNA (renamed MIP-I cDNA). The MIP-II cDNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and A and B chains; however, in this case connected by two distinct C Peptides, Cα and Cβ, instead of a single C Peptide, a phenomenon which represents a new development in the prohormone organization of Peptides belonging to the insulin superfamily. The A and B chains of MIP II and I differ remarkably in primary structure; in contrast, the Cα Peptide domains are fully identical. MIP II has only limited sequence similarity with insulins and related Peptides. Both MIP II and I exhibit structural features, which make them a unique class of the insulin superfamily. The MIP I and II genes are expressed in a single type of neuron: the growth-controlling neuroendocrine light green cells of the Lymnaea CNS.

Maoxian He - One of the best experts on this subject based on the ideXlab platform.

  • pfirr interacts with hrigf i and activates the map kinase and pi3 kinase signaling pathways to regulate glycogen metabolism in pinctada fucata
    Scientific Reports, 2016
    Co-Authors: Maoxian He
    Abstract:

    The insulin-induced mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathways are major intracellular signaling modules and conserved among eukaryotes that are known to regulate diverse cellular processes. However, they have not been investigated in the mollusk species Pinctada fucata. Here, we demonstrate that Insulin-Related Peptide receptor of P. fucata (pfIRR) interacts with human recombinant insulin-like growth factor I (hrIGF-I), and stimulates the MAPK and PI3K signaling pathways in P. fucata oocytes. We also show that inhibition of pfIRR by the inhibitor PQ401 significantly attenuates the basal and hrIGF-I-induced phosphorylation of MAPK and PI3K/Akt at amino acid residues threonine 308 and serine 473. Furthermore, our experiments show that there is cross-talk between the MAPK and PI3K/Akt pathways, in which MAPK kinase positively regulates the PI3K pathway, and PI3K positively regulates the MAPK cascade. Intramuscular injection of hrIGF-I stimulates the PI3K and MAPK pathways to increase the expression of pfirr, protein phosphatase 1, glucokinase, and the phosphorylation of glycogen synthase, decreases the mRNA expression of glycogen synthase kinase-3 beta, decreases glucose levels in hemocytes, and increases glycogen levels in digestive glands. These results suggest that the MAPK and PI3K pathways in P. fucata transmit the hrIGF-I signal to regulate glycogen metabolism.

  • molecular identification of insulin related Peptide receptor and its potential role in regulating development in pinctada fucata
    Aquaculture, 2013
    Co-Authors: Yunyan Guan, Maoxian He
    Abstract:

    The insulin-like family is not only an important regulatory factor for animal growth, development, and metabolism, but also a mediator for initiating growth activity of growth hormone. It plays an important role in transferring transmembrane information and regulating cell function by binding to tyrosine kinase receptors (insulin receptors). To better understand the role of Insulin-Related Peptide receptor (Pfirr) on the developmental regulation in Pinctada fucata, 5.326 kb encoding cDNAs for Pfirr have been cloned and functionally characterized. Pfirr displays significant homologies to Crassostrea gigas, and exhibits all the typical features of insulin receptors and tyrosine kinase domain structure, both of which are typical for the protein family sharing high similarity to other orthologs. Real-time PCR analyses show that Pfirr widely expresses in tissues and developmental stages of P. fucata. Expression of Pfirr mRNAs at different developmental stages (polar body stage, the trocophore stage and D-shaped larva stage) following treatment with agonist IGF-I(1, 2, 4 and 8 mu M/L) and antagonist PQ401 (5, 15, 25, 50 and 100 mu M/L) indicated that Pfirr may be involved in regulating the development of embryos in P. fucata. These results clearly demonstrate Pfirr is involved in regulating developmental process in P. fucata. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.

Yunyan Guan - One of the best experts on this subject based on the ideXlab platform.

  • molecular identification of insulin related Peptide receptor and its potential role in regulating development in pinctada fucata
    Aquaculture, 2013
    Co-Authors: Yunyan Guan, Maoxian He
    Abstract:

    The insulin-like family is not only an important regulatory factor for animal growth, development, and metabolism, but also a mediator for initiating growth activity of growth hormone. It plays an important role in transferring transmembrane information and regulating cell function by binding to tyrosine kinase receptors (insulin receptors). To better understand the role of Insulin-Related Peptide receptor (Pfirr) on the developmental regulation in Pinctada fucata, 5.326 kb encoding cDNAs for Pfirr have been cloned and functionally characterized. Pfirr displays significant homologies to Crassostrea gigas, and exhibits all the typical features of insulin receptors and tyrosine kinase domain structure, both of which are typical for the protein family sharing high similarity to other orthologs. Real-time PCR analyses show that Pfirr widely expresses in tissues and developmental stages of P. fucata. Expression of Pfirr mRNAs at different developmental stages (polar body stage, the trocophore stage and D-shaped larva stage) following treatment with agonist IGF-I(1, 2, 4 and 8 mu M/L) and antagonist PQ401 (5, 15, 25, 50 and 100 mu M/L) indicated that Pfirr may be involved in regulating the development of embryos in P. fucata. These results clearly demonstrate Pfirr is involved in regulating developmental process in P. fucata. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  • Molecular identification of Insulin-Related Peptide receptor and its potential role in regulating development in Pinctada fucata
    Aquaculture, 2013
    Co-Authors: Yu Shi, Yunyan Guan
    Abstract:

    AbstractThe insulin-like family is not only an important regulatory factor for animal growth, development, and metabolism, but also a mediator for initiating growth activity of growth hormone. It plays an important role in transferring transmembrane information and regulating cell function by binding to tyrosine kinase receptors (insulin receptors). To better understand the role of Insulin-Related Peptide receptor (Pfirr) on the developmental regulation in Pinctada fucata, 5.326kb encoding cDNAs for Pfirr have been cloned and functionally characterized. Pfirr displays significant homologies to Crassostrea gigas, and exhibits all the typical features of insulin receptors and tyrosine kinase domain structure, both of which are typical for the protein family sharing high similarity to other orthologs. Real-time PCR analyses show that Pfirr widely expresses in tissues and developmental stages of P. fucata. Expression of Pfirr mRNAs at different developmental stages (polar body stage, the trocophore stage and D-shaped larva stage) following treatment with agonist IGF-I(1, 2, 4 and 8μM/L) and antagonist PQ401 (5, 15, 25, 50 and 100μM/L) indicated that Pfirr may be involved in regulating the development of embryos in P. fucata. These results clearly demonstrate Pfirr is involved in regulating developmental process in P. fucata

A.b. Smit - One of the best experts on this subject based on the ideXlab platform.

  • Expression and characterization of molluscan Insulin-Related Peptide VII from the molluscLymnaea stagnalis
    Neuroscience, 1996
    Co-Authors: A.b. Smit, Sabine Spijker, J. Van Minnen, Julian F. Burke, F. De Winter, R. Van Elk, Wijnand P. M. Geraerts
    Abstract:

    A complementary DNA clone encoding molluscan Insulin-Related Peptide VII was identified from a complementary DNA library of the cerebral ganglia of the CNS of the freshwater snail, Lymnaea stagnalis. The novel molluscan Insulin-Related Peptide VII complementary DNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and an A and B chain, and is connected by an unusual long C Peptide. The A and B chains, as well as the C Peptide of molluscan Insulin-Related Peptide VII, differ remarkably in primary structure with the previously identified molluscan Insulin-Related Peptides. The C Peptide of molluscan Insulin-Related Peptide VII shares no significant sequence identity with counterparts in other molluscan Insulin-Related Peptides. Both molluscan Insulin-Related Peptide VII and the other molluscan Insulin-Related Peptides exhibit structural features which make them a unique class of the insulin superfamily. Molluscan Insulin-Related Peptide VII complementary DNA was shown to hybridize in situ with messenger RNA present in the cerebral light green cells, neuroendocrine cells that control growth and that have previously been shown to produce molluscan Insulin-Related Peptides I-III and V. Uniquely, the molluscan Insulin-Related Peptide VII gene is also expressed in neurons that may form part of the feeding circuitry in Lymnaea, indicating that it may function as a neurotransmitter/neuromodulator.

  • Evolutionary conservation of the insulin gene structure in invertebrates: cloning of the gene encoding molluscan Insulin-Related Peptide III from Lymnaea stagnalis
    Journal of molecular endocrinology, 1993
    Co-Authors: A.b. Smit, R. Van Elk, Harm Van Heerikhuizen, A. Van Marle, Jan Bogerd, Wijnand P. M. Geraerts
    Abstract:

    Although insulins and structurally related Peptides are found in vertebrates as well as in invertebrates, it is not clear whether the genes encoding these hormones have emerged from a single ancestral (insulin)-type of gene or, alternatively, have arisen independently through convergent evolution from different types of gene. To investigate this issue, we cloned the gene encoding the molluscan Insulin-Related Peptide III (MIP III) from the freshwater snail, Lymnaea stagnalis. The predicted MIP III preprohormone had the overall organization of preproinsulin, with a signal Peptide and A and B chains, connected by two putative C Peptides. Although MIP III was found to share key features with vertebrate insulins, it also had unique structural characteristics in common with the previously identified MIPs I and II, thus forming a distinct class of MIP Peptides within the insulin superfamily. MIP III is synthesized in neurones in the brain. It is encoded by a gene with the overall organization of the vertebrate insulin genes, with three exons and two introns, of which the second intron interrupts the coding region of the C Peptides. Our data therefore demonstrate that in the Archaemetazoa, the common ancestor of the vertebrates and invertebrates, a primordial Peptide with a two-chain insulin configuration encoded by a primordial insulin-type gene must have been present.

  • Characterization of a cDNA clone encoding molluscan Insulin-Related Peptide V of Lymnaea stagnalis.
    Brain research. Molecular brain research, 1992
    Co-Authors: A.b. Smit, Wijnand P. M. Geraerts, Irene Meester, Harm Van Heerikhuizen, Steven F. T. Thijsen, J. Joosse
    Abstract:

    A cDNA clone encoding molluscan Insulin-Related Peptide V (MIP V) was isolated from a cDNA library of the central nervous system (CNS) of the freshwater snail, Lymnaea stagnalis, using a heterologous screening with a previously identified MIP II cDNA. The MIP V cDNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and an A and B chain, however, in this case connected by two distinct C Peptide, C alpha and C beta, instead of one single C Peptide. This phenomenon, which is shared by the MIP II precursor, represents a new development in the prohormone organization of Peptides belonging to the insulin superfamily. The A and B chains of MIPs V, I and II, differ remarkably in primary structure; in contrast, the C alpha Peptide domains are almost identical. MIP V has only limited sequence similarity with insulins and related Peptides. Both MIP V and I exhibit structural features, which make them a unique class of the insulin superfamily. The MIP I, II and V genes are expressed in a single type of neuron: the growth controlling neuroendocrine light green cells of the Lymnaea CNS.

  • Characterization of a cDNA clone encoding molluscan insulin‐related Peptide II of Lymnaea stagnalis
    European journal of biochemistry, 1991
    Co-Authors: A.b. Smit, Wijnand P. M. Geraerts, Irene Meester, Harm Van Heerikhuizen, J. Joosse
    Abstract:

    A cDNA clone encoding molluscan Insulin-Related Peptide (MIP) II was isolated from a cDNA library of the central nervous system (CNS) of the freshwater snail, Lymnaea stagnalis, using a heterologous screening with a previously identified MIP cDNA (renamed MIP-I cDNA). The MIP-II cDNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and A and B chains; however, in this case connected by two distinct C Peptides, Cα and Cβ, instead of a single C Peptide, a phenomenon which represents a new development in the prohormone organization of Peptides belonging to the insulin superfamily. The A and B chains of MIP II and I differ remarkably in primary structure; in contrast, the Cα Peptide domains are fully identical. MIP II has only limited sequence similarity with insulins and related Peptides. Both MIP II and I exhibit structural features, which make them a unique class of the insulin superfamily. The MIP I and II genes are expressed in a single type of neuron: the growth-controlling neuroendocrine light green cells of the Lymnaea CNS.