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Fang ZH, Bovenhuis H, van Valenberg HJF, Martin P, Huppertz T, Visker MHPW. Genetic parameters for α S1-casein and α S2-casein phosphorylation isoforms in Dutch Holstein Friesian. J Dairy Sci 2017; 101:1281-1291. [PMID: 29224882 DOI: 10.3168/jds.2017-13623] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/10/2017] [Indexed: 11/19/2022]
Abstract
Relative concentrations of αS1-casein and αS2-casein (αS1-CN and αS2-CN) phosphorylation isoforms vary considerably among milk of individual cows. We estimated heritabilities for αS2-CN phosphorylation isoforms, determined by capillary zone electrophoresis from 1,857 morning milk samples, and genetic correlations among αS2-CN phosphorylation isoforms in Dutch Holstein Friesian. To investigate if phosphorylation of αS1-CN and αS2-CN are due to the same genetic mechanism, we also estimated genetic correlations between αS1-CN and αS2-CN phosphorylation isoforms as well as the genetic correlations between the phosphorylation degrees (PD) of αS1-CN and αS2-CN defined as the proportion of isoforms with higher degrees of phosphorylation in total αS1-CN and αS2-CN, respectively. The intra-herd heritabilities for the relative concentrations of αS2-CN phosphorylation isoforms were high and ranged from 0.54 for αS2-CN-10P to 0.89 for αS2-CN-12P. Furthermore, the high intra-herd heritabilities of αS1-CN PD and αS2-CN PD imply a strong genetic control of the phosphorylation process, which is independent of casein production. The genetic correlations between αS2-CN phosphorylation isoforms are positive and moderate to high (0.33-0.90). Furthermore, the strong positive genetic correlation (0.94) between αS1-CN PD and αS2-CN PD suggests that the phosphorylation processes of αS1-CN and αS2-CN are related. This study shows the possibility of breeding for specific αS1-CN and αS2-CN phosphorylation isoforms, and relations between the phosphorylation degrees of αS1-CN and αS2-CN and technological properties of milk need to be further investigated to identify potential benefits for the dairy industry.
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Affiliation(s)
- Z H Fang
- Génétique Animale et Biologie Intégrative, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France; Animal Breeding and Genomics Centre, Wageningen University and Research, PO Box 338, 6700 AH Wageningen, the Netherlands
| | - H Bovenhuis
- Animal Breeding and Genomics Centre, Wageningen University and Research, PO Box 338, 6700 AH Wageningen, the Netherlands
| | - H J F van Valenberg
- Dairy Science and Technology Group, Wageningen University, PO Box 17, 6700 AA, Wageningen, the Netherlands
| | - P Martin
- Génétique Animale et Biologie Intégrative, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - T Huppertz
- NIZO, PO Box 20, 6710 BA, Ede, the Netherlands
| | - M H P W Visker
- Animal Breeding and Genomics Centre, Wageningen University and Research, PO Box 338, 6700 AH Wageningen, the Netherlands.
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Le Parc A, Honvo Houéto E, Pigat N, Chat S, Leonil J, Chanat E. The membrane-associated form of α(s1)-casein interacts with cholesterol-rich detergent-resistant microdomains. PLoS One 2014; 9:e115903. [PMID: 25549363 PMCID: PMC4280128 DOI: 10.1371/journal.pone.0115903] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 12/02/2014] [Indexed: 12/19/2022] Open
Abstract
Caseins, the main milk proteins, interact with colloidal calcium phosphate to form the casein micelle. The mesostructure of this supramolecular assembly markedly influences its nutritional and technological functionalities. However, its detailed molecular organization and the cellular mechanisms involved in its biogenesis have been only partially established. There is a growing body of evidence to support the concept that α(s1)-casein takes center stage in casein micelle building and transport in the secretory pathway of mammary epithelial cells. Here we have investigated the membrane-associated form of α(s1)-casein in rat mammary epithelial cells. Using metabolic labelling we show that α(s1)-casein becomes associated with membranes at the level of the endoplasmic reticulum, with no subsequent increase at the level of the Golgi apparatus. From morphological and biochemical data, it appears that caseins are in a tight relationship with membranes throughout the secretory pathway. On the other hand, we have observed that the membrane-associated form of α(s1)-casein co-purified with detergent-resistant membranes. It was poorly solubilised by Tween 20, partially insoluble in Lubrol WX, and substantially insoluble in Triton X-100. Finally, we found that cholesterol depletion results in the release of the membrane-associated form of α(s1)-casein. These experiments reveal that the insolubility of α(s1)-casein reflects its partial association with a cholesterol-rich detergent-resistant microdomain. We propose that the membrane-associated form of α(s1)-casein interacts with the lipid microdomain, or lipid raft, that forms within the membranes of the endoplasmic reticulum, for efficient forward transport and sorting in the secretory pathway of mammary epithelial cells.
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Affiliation(s)
- Annabelle Le Parc
- UR1196 Génomique et Physiologie de la Lactation, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
| | - Edith Honvo Houéto
- UR1196 Génomique et Physiologie de la Lactation, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
| | - Natascha Pigat
- UR1196 Génomique et Physiologie de la Lactation, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
| | - Sophie Chat
- UR1196 Génomique et Physiologie de la Lactation, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
| | - Joëlle Leonil
- UMR1253 Science et Technologie du Lait et de l'Œuf, Institut National de la Recherche Agronomique, Rennes, France
| | - Eric Chanat
- UR1196 Génomique et Physiologie de la Lactation, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
- * E-mail:
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3
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Le Parc A, Leonil J, Chanat E. AlphaS1-casein, which is essential for efficient ER-to-Golgi casein transport, is also present in a tightly membrane-associated form. BMC Cell Biol 2010; 11:65. [PMID: 20704729 PMCID: PMC2928771 DOI: 10.1186/1471-2121-11-65] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Accepted: 08/12/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Caseins, the main milk proteins, aggregate in the secretory pathway of mammary epithelial cells into large supramolecular structures, casein micelles. The role of individual caseins in this process and the mesostructure of the casein micelle are poorly known. RESULTS In this study, we investigate primary steps of casein micelle formation in rough endoplasmic reticulum-derived vesicles prepared from rat or goat mammary tissues. The majority of both alphaS1- and beta-casein which are cysteine-containing casein was dimeric in the endoplasmic reticulum. Saponin permeabilisation of microsomal membranes in physico-chemical conditions believed to conserve casein interactions demonstrated that rat immature beta-casein is weakly aggregated in the endoplasmic reticulum. In striking contrast, a large proportion of immature alphaS1-casein was recovered in permeabilised microsomes when incubated in conservative conditions. Furthermore, a substantial amount of alphaS1-casein remained associated with microsomal or post-ER membranes after saponin permeabilisation in non-conservative conditions or carbonate extraction at pH11, all in the presence of DTT. Finally, we show that protein dimerisation via disulfide bond is involved in the interaction of alphaS1-casein with membranes. CONCLUSIONS These experiments reveal for the first time the existence of a membrane-associated form of alphaS1-casein in the endoplasmic reticulum and in more distal compartments of the secretory pathway of mammary epithelial cells. Our data suggest that alphaS1-casein, which is required for efficient export of the other caseins from the endoplasmic reticulum, plays a key role in early steps of casein micelle biogenesis and casein transport in the secretory pathway.
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Affiliation(s)
- Annabelle Le Parc
- INRA, UR1196 Génomique et Physiologie de la Lactation, Domaine de Vilvert, F-78352 Jouy-en-Josas cedex, France
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4
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Ghaffari A, Li Y, Kilani RT, Ghahary A. 14-3-3 sigma associates with cell surface aminopeptidase N in the regulation of matrix metalloproteinase-1. J Cell Sci 2010; 123:2996-3005. [PMID: 20699358 DOI: 10.1242/jcs.069484] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Matrix metalloproteinases (MMPs) are implicated in the degradation of the extracellular matrix during development and tissue repair, as well as in pathological conditions such as tumor invasion and fibrosis. MMP expression by stromal cells is partly regulated by signals from the neighboring epithelial cells. Keratinocyte-releasable 14-3-3sigma, or stratifin, acts as a potent MMP-1-stimulatory factor in fibroblasts. However, its mechanism of transmembrane signaling remains unknown. Ectodomain biotin labeling, serial affinity purification and mass spectroscopy analysis revealed that the stratifin associates with aminopeptidase N (APN), or CD13, at the cell surface. The transient knockdown of APN in fibroblasts eliminated the stratifin-mediated p38 MAP kinase activation and MMP-1 expression, implicating APN in a receptor-mediated transmembrane signaling event. Stratifin deletion studies implicated its C-terminus as a potential APN-binding site. Furthermore, the dephosphorylation of APN ectodomains reduced its binding affinity to the stratifin. The presence of a phosphorylated serine or threonine residue in APN has been implicated. Together, these findings provide evidence that APN is a novel cell surface receptor for stratifin and a potential target in the regulation of MMP-1 expression in epithelial-stromal cell communication.
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Affiliation(s)
- Abdi Ghaffari
- Department of Surgery, BC Professional Firefighter's Burn and Wound Healing Research Laboratory, University of British Columbia, 344A JBRC, 2660 Oak Street, Vancouver, Canada, BC V6H 3Z6
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Kinoshita M, Era T, Jakt LM, Nishikawa SI. The novel protein kinase Vlk is essential for stromal function of mesenchymal cells. Development 2009; 136:2069-79. [PMID: 19465597 DOI: 10.1242/dev.026435] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
From a list of protein kinases (PKs) that are newly induced upon differentiation of mouse embryonic stem cells to mesendoderm, we identified a previously uncharacterized kinase, Vlk (vertebrate lonesome kinase), that is well conserved in vertebrates but has no homologs outside of the vertebrate lineage. Its kinase domain cannot be classified into any of the previously defined kinase groups or families. Although Vlk is first expressed in E-cadherin-positive anterior visceral endoderm and mesendoderm, its expression is later confined to E-cadherin-negative mesenchyme. Vlk is enriched in the Golgi apparatus and blocks VSVG transport from the Golgi to the plasma membrane. Targeted disruption of Vlk leads to a defect in lung development and to delayed ossification of endochondral bone. Vlk(-/-) mice display neonatal lethality due to respiratory failure, with a suckling defect arising from a cleft palate. Our results demonstrate that Vlk is a novel vertebrate-specific PK that is involved in the regulation of the rate of protein export from the Golgi, thereby playing an important role in the formation of functional stroma by mesenchymal cells.
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Affiliation(s)
- Masaki Kinoshita
- Laboratory for Stem Cell Biology, RIKEN Center for Developmental Biology, Chuo-ku, Kobe 650-0047, Japan.
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6
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Lipid-deprived diet perturbs O-glycosylation of secretory proteins in rat mammary epithelial cells. Animal 2008; 2:491-9. [DOI: 10.1017/s1751731107001309] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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7
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Horne DS, Anema S, Zhu X, Nicholas KR, Singh H. A lactational study of the composition and integrity of casein micelles from the milk of the tammar wallaby (Macropus eugenii). Arch Biochem Biophys 2007; 467:107-18. [PMID: 17884009 DOI: 10.1016/j.abb.2007.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Accepted: 08/03/2007] [Indexed: 10/22/2022]
Abstract
The amount of casein found in the milk of the tammar wallaby increases as lactation progresses. The increase is due to increasing amounts of beta-casein; the alpha-casein remains largely constant. The alpha-casein is the more highly phosphorylated; the most abundant form is the 10-P, throughout lactation. The level of phosphorylation of beta-casein shifts to lower average values in late lactation, possibly indicating the enzymatic reaction is overloaded by the increasing amounts of beta-casein. Unlike bovine casein micelles, the wallaby micelles are not completely disrupted at pH 7.0 by sequestration of their calcium content with ethylene diamine tetraacetic acid (EDTA). Complete disruption only follows the addition of sodium dodecyl sulphate, indicating considerably greater importance for hydrophobic bonds in maintaining their integrity. This micellar behaviour indicates that, despite the evolutionary divergence of marsupials millennia ago, the caseins of wallaby milk assemble into micelles in much the same fashion as in bovine milk.
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Péchoux C, Boisgard R, Chanat E, Lavialle F. Ca(2+)-independent phospholipase A2 participates in the vesicular transport of milk proteins. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1743:317-29. [PMID: 15843044 DOI: 10.1016/j.bbamcr.2005.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Revised: 01/12/2005] [Accepted: 01/13/2005] [Indexed: 11/16/2022]
Abstract
Changes in the lipid composition of intracellular membranes are believed to take part in the molecular processes that sustain traffic between organelles of the endocytic and exocytic transport pathways. Here, we investigated the participation of the calcium-independent phospholipase A2 in the secretory pathway of mammary epithelial cells. Treatment with bromoenol lactone, a suicide substrate which interferes with the production of lysophospholipids by the calcium-independent phospholipase A2, resulted in the reduction of milk proteins secretion. The inhibitor slowed down transport of the caseins from the endoplasmic reticulum to the Golgi apparatus and affected the distribution of p58 and p23, indicating that the optimal process of transport of these proteins between the endoplasmic reticulum, the endoplasmic reticulum/Golgi intermediate compartment and/or the cis-side of the Golgi was dependent upon the production of lysolipids. Moreover, bromoenol lactone was found to delay the rate of protein transport from the trans-Golgi network to the plasma membrane. Concomitantly, membrane-bound structures containing casein accumulated in the juxtanuclear Golgi region. We concluded from these results that efficient formation of post-Golgi carriers also requires the phospholipase activity. These data further support the participation of calcium-independent phospholipase A2 in membrane trafficking and shed a new light on the tubulo/vesicular transport of milk protein through the secretory pathway.
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Affiliation(s)
- Christine Péchoux
- Institut National de la Recherche Agronomique, Laboratoire de Génomique et Physiologie de la Lactation. F-78352 Jouy-en-Josas Cedex, France
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9
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Boisgard R, Chanat E, Lavialle F, Pauloin A, Ollivier-Bousquet M. Roads taken by milk proteins in mammary epithelial cells. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0301-6226(01)00197-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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10
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Drzymala L, Castle A, Cheung JC, Bennick A. Cellular phosphorylation of an acidic proline-rich protein, PRP1, a secreted salivary phosphoprotein. Biochemistry 2000; 39:2023-31. [PMID: 10684652 DOI: 10.1021/bi9924213] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phosphorylation of many secreted salivary proteins is necessary for their biological functions. Identification of the kinase, which is responsible for in vivo phosphorylation, is complicated, because several of the protein phosphorylation sites conform both to the recognition sequence of casein kinase 2 (CK2) and Golgi kinase (G-CK), which both are found in the secretory pathway. This study was undertaken to determine the kinase recognition sequence in a secreted proline-rich salivary protein, PRP1, and thereby identify the responsible kinase. This was done by transfecting a human submandibular cell line, HSG, and a kidney cell line, HEK293, with expression vectors encoding wild-type or mutated PRP1. It was shown that phosphorylation occurred only at the same sites, Ser8 and 22, as in PRP1 purified from saliva. Phosphorylation at either site did not depend on the other site being phosphorylated. The sequence surrounding Ser8 has characteristics of both CK2 and G-CK recognition sequences, but destruction of the CK2 recognition site had no effect on phosphorylation, whereas no phosphorylation occurred if the G-CK recognition sequence was altered. The sequence surrounding Ser22 did not conform to any known kinase recognition sites. If Ser22 was mutated to Thr, no phosphorylation was seen, and a cluster of negatively charged residues at positions 27-29 was identified as part of the enzyme recognition site. Ser22 may be phosphorylated by a G-CK that recognizes an atypical substrate sequence or by a novel kinase. No difference in phosphorylation was seen between undifferentiated and differentiated HSG cells.
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Affiliation(s)
- L Drzymala
- Department of Biochemistry, University of Toronto, Toronto M5S 1A8, Canada
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11
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Boisgard R, Chanat E. Phospholipase D-dependent and -independent mechanisms are involved in milk protein secretion in rabbit mammary epithelial cells. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1495:281-96. [PMID: 10699466 DOI: 10.1016/s0167-4889(99)00167-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Phospholipase D has been implicated in membrane traffic in the secretory pathway of yeast and of some mammalian cell lines. Here we investigated the involvement of phospholipase D in protein transport at various steps of the secretory pathway of mammary epithelial cells. Treatment of rabbit mammary explants with butanol, which blocks the formation of phosphatidic acid, decreased the secretion of caseins and to a lesser extent that of whey acidic protein. Butanol interfered with both the endoplasmic reticulum to Golgi complex transport of the caseins and secretory vesicle formation from the trans-Golgi network. In contrast, the transport of whey acidic protein to the Golgi was less affected. Activation of protein kinase C enhanced the overall secretion of both markers and interestingly, this stimulation of secretion was maintained for whey acidic protein in the presence of butanol. Transphosphatidylation assays demonstrated the existence of a constitutive phospholipase D activity which was stimulated by the activation of protein kinase C. We conclude that phospholipase D plays a role in casein transport from the endoplasmic reticulum to the Golgi and in the secretory vesicle formation from the trans-Golgi network. Moreover, our results suggest a differential requirement for phospholipase D in the secretion of caseins and that of whey acidic protein.
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Affiliation(s)
- R Boisgard
- Institut National de la Recherche Agronomique, Laboratoire de Biologie Cellulaire et Moleculaire, F-78352, Jouy-en-Josas, France
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12
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Peterkofsky B, Gosiewska A, Wilson S, Kim YR. Phosphorylation of rat insulin-like growth factor binding protein-1 does not affect its biological properties. Arch Biochem Biophys 1998; 357:101-10. [PMID: 9721188 DOI: 10.1006/abbi.1998.0797] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Insulin-like growth factors (IGFs) I and II stimulate growth and expression of specific genes through binding to cell membrane receptors. IGF binding proteins also bind IGF-I with higher affinity than the receptor. They are found in the circulation and tissues and can modulate IGF actions. Human IGFBP-1 is phosphorylated on serine residues, which increases its affinity for IGF-I. An acidic, presumably phosphorylated, form of human IGFBP-1 inhibits IGF-I-stimulated DNA synthesis in cultured cells, while a less acidic, unphosphorylated form potentiates this function. Phosphorylation of human IGFBP-3, however, does not affect its affinity for IGF-I. Previously we found that multiple forms of rat IGFBP-1 are obtained by anion-exchange chromatography, raising the possibility that it also is phosphorylated, which led us to examine its properties. Phosphopeptide analysis of 32P-labeled, immunoprecipitated rat IGFBP-1 synthesized by H-4-II-EC3 rat hepatoma cells indicated that it is phosphorylated on two sites that were deduced to be ser107 and ser132 in the central nonconserved domain. Dephosphorylation of purified phosphorylated rat IGFBP-1 did not affect its affinity for IGF-I or its specific binding activity, and the dephosphorylated form inhibited DNA synthesis in 3T3 cells. Incubation of cells labeled with radioactive proline in the presence of monensin and brefeldin A, which inhibit secretion at different sites, led to intracellular accumulation of the least phosphorylated form of rat IGFBP-1, but prevented further phosphorylation. The results suggested that phosphorylation occurs at two sites in cells, the cis-Golgi and the trans-Golgi network. In summary, these studies have shown that rat IGFBP-1 is phosphorylated on two sites by reactions that occur in different secretory organelles and that similar to human IGFBP-3, but unlike human IGFBP-1, phosphorylation does not affect its affinity for IGF-I.
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Affiliation(s)
- B Peterkofsky
- Laboratory of Biochemistry, National Cancer Institute, Bethesda, Maryland 20982-4255, USA.
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13
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Clegg RA, Gardner RA, Lavialle F, Boisgard R, Ollivier-Bousquet M. Casein secretion in mammary tissue: tonic regulation of basal secretion by protein kinase A. Mol Cell Endocrinol 1998; 141:163-77. [PMID: 9723897 DOI: 10.1016/s0303-7207(98)00080-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Despite its quantitative importance in the secretion of lactoproteins, little is known about the triggering and control mechanisms that initiate, regulate and terminate the operation of the basal pathway of lactoprotein secretion throughout the lactation cycle. This study investigated the possible modulation by cAMP-mediated mechanisms, of cellular transit of newly-synthesised caseins and their basal secretion in explants of mammary tissue from lactating rats and rabbits. Enhancement of the rate of secretion of newly-synthesised caseins occurs when mammary explants are challenged in vitro with agents that activate protein kinase A (PKA). Inhibition of PKA slows casein secretion. The PKA-sensitive step(s) in casein secretion is early in the exocytosis pathway but inhibition of PKA does not impair casein maturation. Ultrastructural, immunochemical and biochemical methods locate PKA on membranes of vesicles situated in the Golgi region. Exposure of tissue to a cell-permeant PKA inhibitor results in morphological modification of these vesicular structures. We conclude that PKA mediates tonic positive regulation of the basal secretory pathway for lactoproteins in the mammary epithelial cell.
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Affiliation(s)
- R A Clegg
- Hannah Research Institute, Ayr, Scotland, UK.
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14
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Varro A, Henry J, Vaillant C, Dockray G. Discrimination between temperature- and brefeldin A-sensitive steps in the sulfation, phosphorylation, and cleavage of progastrin and its derivatives. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32058-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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15
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Affiliation(s)
- R D Burgoyne
- Physiological Laboratory, University of Liverpool, U.K
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