Glycodelin (GD) also known as human placental protein-14 (PP-14) progestogen-associated endometrial protein (PAEP) or pregnancy-associated endometrial alpha-2 globulin is a glycoprotein that inhibits cell immune function and plays an essential role in the pregnancy process. In humans is encoded by the PAEP gene.[3][4]
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| Aliases | PAEP, GD, GdA, GdF, GdS, PAEG, PEP, PP14, progestagen associated endometrial protein, ZIF-1 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| External IDs | OMIM: 173310; HomoloGene: 99710; GeneCards: PAEP; OMA:PAEP - orthologs | ||||||||||||||||||||||||||||||||||||||||||||||||||
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Human endometrium synthesizes several proteins under the influence of progesterone. Of these proteins, glycodelin is of particular interest. It is synthesized by the endometrial glands in the luteal phase of menstrual cycle.[5]
The temporal and spatial expression of GD in the female reproductive tract combined with its biological activities suggest that this glycoprotein probably plays an essential physiological role in the regulation of fertilization, implantation and maintenance of pregnancy.[6][7]
Structure
edit
Glycodelin is codified by 180 amino acid but it is thought that 18 of these are supposed signals peptides. The molecular weight of GD is 20,555, while its mature form is estimated to weigh 18,787. It is encoded by a 1-kilobase-pair mRNA that is expressed in human secretory endometrium and decidua but not in postmenopausal endometrium, placenta, liver, kidney, and adrenals. The four cysteinyl residues (positions 66, 106, 119, and 160) responsible for intramolecular disulfide bridges in lactoglobulins are all conserved in GD. Southern blot analysis of human DNA suggested that GD gene sequences compass some 20 kilobase pairs of the human genomic DNA.[8]
N-terminal amino acid sequence
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The N-terminal amino acid sequence of glycodelin is M D I P Q T K Q D L E L P K L A G T W H S M. This sequence can be compared with horse, sheep, goat, bovine and buffalo beta-lactoglobulin. For example, there are 13 identities out of 22 possible matches with horse beta-lactoglobulin.
PAEP gene
editThis gene is a member of the kernel lipocalin superfamily whose members share relatively low sequence similarity but have highly conserved exon-intron structure and three-dimensional protein folding. The PAEP gene is clustered on the long arm of chromosome 9 and encodes for GD protein. It is mainly expressed in 60 organs, but reaches its highest expression level in the decidua.[9][10]
Function
editGD is the most important protein secreted in the endometrium during the mid-luteal phase of the menstrual cycle and during the first semester of pregnancy. Four distinct forms of glycoprotein, with identical protein backbones but different glycosylation profiles, are found in amniotic fluid, follicular fluid and seminal plasma of the reproductive system. These glycoproteins have distinct and essential roles in regulating a uterine environment suitable for pregnancy and in the timing and occurrence of the appropriate sequence of events in the fertilization process.
Glycodelin-A
editIn the female genital tract is mainly expressed in EECs (cultured endometrial epithelial cells) and secreted into the amniotic fluid, endometrium/decidua and maternal serum. Glycodelin-A has contraceptive and immunosuppressive functions, due to the fact that suppresses Natural Killer cells, achieving the prevention of the maternal rejection of the fetus at the fetromaternal interface. It has a molecular weight of 18.78 KDa determined from the cRNA sequence.[11][12][13]
Glycodelin-S
editIs secreted from seminal vesicles to the seminal fluid. A number of alternatively spliced transcript variants have been observed at this locus, but the full-length nature of only two, each encoding the same protein, has been determined. During the passage of the sperm through the cervix, glycodelin S is de-glycosylated and dissociates from the sperm, allowing the sperm to mature.[14][15][16]
Glycodelin-F
editIs secreted by granulosa cells into the follicular fluid. Glycodelin-F reduces the blinding of spermatozoa to the zona pellucida which is mainly expressed in the ovary, and synthesised in the granulosa cells, has a function in principle similar to that of Glycodelin-A. It also binds the sperm head, thereby inhibiting acrosome reaction and sperm-egg binding. Upon de-glycosilation, glycodelin F dissociates from the sperm and sperm-egg binding is possible. The de-glycosilation takes place during the passage of the sperm through the corona cell layer. Glycodelin F is thereby important to prevent a premature acrosome reaction.[17][18]
Glycodelin-C
editFound in Cumulus Oophorus, stimulates binding of the spermatozoa to the zona pellucida. First, cumulus cells reduce the spermatozoa-zona binding inhibitory activity of follicular fluid probably by taking up and converting glycodelin-A and glycodelin-F into glycodelin-C. Second, spermatozoa have enhanced zona bindig ability after penetrating through the cumulus oophorus. Glycodelin-C is responsible for the latter observation.[19][20]
| GLYCOFORM | SOURCE | GLYCOSYLATION | REPRODUCTIVE FUNCTIONS |
|---|---|---|---|
| GdA | Amniotic fluid, pregnancy decidua | High sialylation, more fucosylation | Immunoprotection for implantation and placentation, antifertilizing, inhibiting spermatozoa-zona pellucida binding |
| GdS | Seminal plasma, seminal vesicles | No sialylated glycans, rich in fucose and mannose | Preventing premature capacitation |
| GdF | Ovarian follicles, oviduct | Fucosylated Lewis-x and Lewis-y, more N-acetylglucosamine | Inhibiting spermatozoa-zona pellucida, preventing premature acrosome reaction |
| GdC | Cumulus oophorus, converted from GdA and GdF | Reacting with specific agglutinins in lectin-binding manner | Stimulating spermatozoa-zona pellucida binding |
Level concentrations
editPP-14 is found in the oocyte and in the sperm. In men, the concentration of this protein in seminal plasma is higher than those in serum. In women, the levels in follicular fluid exceed those of non-pregnant women.[22]
·Seminal plasma:
PP-14 is a significant protein constituent in most seminal plasma samples of men; sometimes comprising over 2.5% of the total protein content. The concentration of PP-14 in seminal plasma from men with oligospermia is in the reference range of this protein derived from values measured in normal men. However, vasectomized men concentrations are less than normal.[23]
·Women's tissues and body fluids:
In serum of non-pregnant women, the concentration of PP-14 is approximately 15-40 μg/L.
In normal pregnancy:
| Location (tissues and body fluids) | PP-14 concentrations (approximately) | Time |
|---|---|---|
| Serum | Up to 2200 μg/L (highest) | 6–12 weeks |
| --- | Decreasing concentrations | After 16 weeks |
| --- | 200 μg/L approx. | 24 weeks (plateaued) |
| Amniotic fluid | 232 mg/L (highest) (higher than those in maternal serum throughout pregnancy) | 12–20 weeks |
| Cord blood | 15-22 μg or undetectable | ------------ |
| Early pregnancy decidua | 41–160 mg/g total protein | ------------ |
| Late pregnancy decidua | 60-2700 μg/g total protein | ------------ |
| Amnion and chorion laeve | From 50 to 750 μg/g protein | ------------ |
| From 50 to 1000 μg/g protein | ------------ | |
| Early pregnancy placenta | 0.25–15 mg/g | ------------ |
| Late pregnancy placenta | 3-430 μg/g protein | ------------ |
The concentrations of PP-14 in pregnancy serum are comparable with hCG (Human Chorionic Gonadotropin). Among all the placental proteins, the amniotic fluid PP-14 concentration is the most outstanding as decidua is a source of this protein.[24]
Future clinical applications
editPlacental Protein 14 has some clinical applications:
1. Biomarker of premature rupture of membranes
Premature rupture of membranes is a common pregnancy complication, taking into account that the current method does not satisfy the medical community, some researches have determined a new method: the analysis of placental protein in the maternal plasma and vaginal fluid. The results of these studies have shown that PP-14's concentration increased in the case of premature rupture of membranes. So this study conclude that PP-14 is an excellent biomarker with a sensibility of 100% and a specificity of 87,5%.[25]
2. Biomarker in in vitro fertilization process
PP-14 is known to be a great marker to predict the outcome of in vitro fertilization and the embryo transfer cycle. Some studies have shown that the serum concentration of Placental Protein 14 was highly increased after the embryo transfer cycle, and they conclude that PP-14 might be an excellent marker to predict the endometrial receptivity.[26]
References
edit- ^ a b c GRCh38: Ensembl release 89: ENSG00000122133 – Ensembl, May 2017
- ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- ^ "PAEP - Glycodelin precursor - Homo sapiens (Human) - PAEP gene & protein". www.uniprot.org.
- ^ Wang, Ping; Libho, Zhu; Xinmei, Zhang (December 2013). "The role of Placental Protein 14 in the Pathogenesis of Endometrosis". Reproductive Sciences. 20 (12): 1465–1470. doi:10.1177/1933719113488452. ISSN 0077-8923. PMC 3817670. PMID 23670949.
- ^ SEPPÄLÄ, MARKKU; JULKUNEN, MERVI; KOSKIMIES, AARNE; LAATIKAINEN, TIMO; STENMAN, ULF–HÅKAN; HUHTALA, MARJA-LIISA (October 1988). "Proteins of the Human Endometrium". Annals of the New York Academy of Sciences. 541 (1): 432–444. Bibcode:1988NYASA.541..432S. doi:10.1111/j.1749-6632.1988.tb22280.x. ISSN 0077-8923. PMID 3195927. S2CID 222073546.
- ^ Dutta, Binita; Mukhopadhyay, Debaditya; Roy, Nita; Das, Goutam; Karande, Anjali A. (December 1998). "Cloning, Expression, Purification, and Immunocharacterization of Placental Protein-14". Protein Expression and Purification. 14 (3): 327–334. doi:10.1006/prep.1998.0961. ISSN 1046-5928. PMID 9882566.
- ^ Julkunen, M.; Seppala, M.; Janne, O. A. (1988-12-01). "Complete amino acid sequence of human placental protein 14: a progesterone-regulated uterine protein homologous to beta-lactoglobulins". Proceedings of the National Academy of Sciences. 85 (23): 8845–8849. Bibcode:1988PNAS...85.8845J. doi:10.1073/pnas.85.23.8845. ISSN 0027-8424. PMC 282603. PMID 3194393.
- ^ Julkunen, M.; Seppala, M.; Janne, O. A. (1988-12-01). "Complete amino acid sequence of human placental protein 14: a progesterone-regulated uterine protein homologous to beta-lactoglobulins". Proceedings of the National Academy of Sciences. 85 (23): 8845–8849. Bibcode:1988PNAS...85.8845J. doi:10.1073/pnas.85.23.8845. ISSN 0027-8424. PMC 282603. PMID 3194393.
- ^ "PAEP progestagen associated endometrial protein [Homo sapiens (human)] - Gene - NCBI". www.ncbi.nlm.nih.gov. Retrieved 2019-10-13.
- ^ "PAEP - Glycodelin precursor - Homo sapiens (Human) - PAEP gene & protein". www.uniprot.org. Retrieved 2019-10-23.
- ^ JULKUNEN, MERVI; KOISTINEN, RIITTA; SJÖBERG, JARI; RUTANEN, EEVA-MARJA; WAHLSTRÖM, TORSTEN; SEPPÄLÄ, MARKKU (May 1986). "Secretory Endometrium Synthesizes Placental Protein 14*". Endocrinology. 118 (5): 1782–1786. doi:10.1210/endo-118-5-1782. ISSN 0013-7227. PMID 3516653.
- ^ Kao, L. C.; Tulac, S.; Lobo, S.; Imani, B.; Yang, J. P.; Germeyer, A.; Osteen, K.; Taylor, R. N.; Lessey, B. A.; Giudice, L. C. (June 2002). "Global Gene Profiling in Human Endometrium during the Window of Implantation". Endocrinology. 143 (6): 2119–2138. doi:10.1210/endo.143.6.8885. ISSN 0013-7227. PMID 12021176.
- ^ Alok, Anshula; Mukhopadhyay, Debaditya; Karande, Anjali A. (May 2009). "Glycodelin A, an immunomodulatory protein in the endometrium, inhibits proliferation and induces apoptosis in monocytic cells". The International Journal of Biochemistry & Cell Biology. 41 (5): 1138–1147. doi:10.1016/j.biocel.2008.10.009. ISSN 1357-2725. PMID 18996219.
- ^ Mandelin, Erik; Koistinen, Hannu; Koistinen, Riitta; Arola, Johanna; Affandi, Biran; Seppälä, Markku (September 2001). "Endometrial expression of glycodelin in women with levonorgestrel-releasing subdermal implants". Fertility and Sterility. 76 (3): 474–478. doi:10.1016/s0015-0282(01)01969-0. ISSN 0015-0282. PMID 11532467.
- ^ Sjöberg, J.; Wahlström, T.; Seppälä, M.; Rutanen, E.-M.; Koistinen, R.; Koskimies, A. I.; Sinosich, M. J.; Teisner, B.; Grudzinskas, J. G. (January 1985). "Seminal Plasma Levels of PAPP-A in Normospermic and Oligospermic Men and Tissue Localization of PAPP-A in the Male Genital Tract". Archives of Andrology. 14 (2–3): 253–261. doi:10.3109/01485018508988308. ISSN 0148-5016. PMID 2415076.
- ^ Koistinen, Hannu; Koistinen, Riitta; Dell, Anne; Morris, Howard R.; Easton, Richard L.; Patankar, Manish S.; Oehninger, Sergio; Clark, Gary F.; Seppälä, Markku (1996). "Glycodelin from seminal plasma is a differentially glycosylated form of contraceptive glycodelin-A". Molecular Human Reproduction. 2 (10): 759–765. doi:10.1093/molehr/2.10.759. ISSN 1360-9947. PMID 9239694.
- ^ Chiu, Philip C. N.; Chung, Man-Kin; Koistinen, Riitta; Koistinen, Hannu; Seppala, Markku; Ho, Pak-Chung; Ng, Ernest H. Y.; Lee, Kai-Fai; Yeung, William S. B. (2006-12-27). "Cumulus Oophorus-associated Glycodelin-C Displaces Sperm-bound Glycodelin-A and -F and Stimulates Spermatozoa-Zona Pellucida Binding". Journal of Biological Chemistry. 282 (8): 5378–5388. doi:10.1074/jbc.m607482200. ISSN 0021-9258. PMID 17192260.
- ^ Kölbl, Alexandra C.; Andergassen, Ulrich; Jeschke, Udo (2015-10-13). "The Role of Glycosylation in Breast Cancer Metastasis and Cancer Control". Frontiers in Oncology. 5: 219. doi:10.3389/fonc.2015.00219. ISSN 2234-943X. PMC 4602128. PMID 26528431.
- ^ Chiu, Philip C. N.; Chung, Man-Kin; Koistinen, Riitta; Koistinen, Hannu; Seppala, Markku; Ho, Pak-Chung; Ng, Ernest H. Y.; Lee, Kai-Fai; Yeung, William S. B. (2006-12-27). "Cumulus Oophorus-associated Glycodelin-C Displaces Sperm-bound Glycodelin-A and -F and Stimulates Spermatozoa-Zona Pellucida Binding". Journal of Biological Chemistry. 282 (8): 5378–5388. doi:10.1074/jbc.m607482200. ISSN 0021-9258. PMID 17192260.
- ^ Yeung, William S.B.; Lee, Kai-Fai; Koistinen, Riitta; Koistinen, Hannu; Seppälä, Markku; Chiu, Philip C.N. (December 2009). "Effects of glycodelins on functional competence of spermatozoa". Journal of Reproductive Immunology. 83 (1–2): 26–30. doi:10.1016/j.jri.2009.04.012. ISSN 0165-0378. PMID 19857900.
- ^ Cui, Juan; Liu, Yanguo; Wang, Xiuwen (2017-11-29). "The Roles of Glycodelin in Cancer Development and Progression". Frontiers in Immunology. 8: 1685. doi:10.3389/fimmu.2017.01685. ISSN 1664-3224. PMC 5712544. PMID 29238349.
- ^ SEPPäLä, MARKKU; KOSKIMIES, AARNE I.; TENHUNEN, ANSSI; RUTANEN, EEVA-MARJA; SJÖBERG, JARI; KOISTINEN, RIITTA; JULKUNEN, MERVI; WAHLSTRÖM, TORSTEN (May 1985). "Pregnancy Proteins in Seminal Plasma, Seminal Vesicles, Preovulatory Follicular Fluid, and Ovary". Annals of the New York Academy of Sciences. 442 (1 In Vitro Fert): 212–226. Bibcode:1985NYASA.442..212S. doi:10.1111/j.1749-6632.1985.tb37522.x. ISSN 0077-8923. PMID 3893267. S2CID 11729995.
- ^ Bolton, A. E.; Pinto-Furtado, L. G.; Andrew, C. E.; Chapman, M. G. (June 1986). "Measurement of the pregnancy-associated proteins, placental protein 14 and pregnancy-associated plasma protein A in human seminal plasma". Clinical Reproduction and Fertility. 4 (3): 233–240. ISSN 0725-556X. PMID 2427179.
- ^ JULKUNEN, MERVI; RUTANEN, EEVA-MARJA; KOSKIMIES, AARNE; RANTA, TAPIO; BOHN, HANS; SEPPALA, MARKKU (November 1985). "Distribution of placental protein 14 in tissues and body fluids during pregnancy". BJOG: An International Journal of Obstetrics and Gynaecology. 92 (11): 1145–1151. doi:10.1111/j.1471-0528.1985.tb03027.x. ISSN 1470-0328. PMID 4063232. S2CID 40266453.
- ^ Yanyun, Haibo, Guanglu, Yanqin, Jun, Qiongli, Qiongli, Linbo, Tao, Wang, Luo, Che, Li, Gao, Yang, Zhou, Gao, Wang. (2018). "Placental protein 14 as a potential biomarker for diagnosis of preterm premature rupture of membranes". Molecular Medicine Reports. 18 (1): 113–122. doi:10.3892/mmr.2018.8967. PMC 6059659. PMID 29749501. Retrieved 25 October 2019.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Suzuki, Fukumine, Sugiyama, Usuda, Yoshichika, Noritaka, Rikikazu, Saburo. (2000). "Clinical Applications of Serum Placental Protein 14 (PP14) Measurement in the IVF-ET Cycle". Journal of Obstetrics and Gynaecology Research. 26 (4): 295–302. doi:10.1111/j.1447-0756.2000.tb01325.x. PMID 11049241. S2CID 22904564. Retrieved 25 October 2019.
{{cite journal}}: CS1 maint: multiple names: authors list (link)
Further reading
edit- Seppälä M, Bohn H, Tatarinov Y (1998). "Glycodelins". Tumour Biology. 19 (3): 213–20. doi:10.1159/000030009. PMID 9591048. S2CID 232276875.
- Salier JP (Oct 2000). "Chromosomal location, exon/intron organization and evolution of lipocalin genes". Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology. 1482 (1–2): 25–34. doi:10.1016/S0167-4838(00)00144-8. PMID 11058744.
- Halttunen M, Kämäräinen M, Koistinen H (Oct 2000). "Glycodelin: a reproduction-related lipocalin". Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology. 1482 (1–2): 149–56. doi:10.1016/S0167-4838(00)00158-8. PMID 11058757.
- Seppälä M, Taylor RN, Koistinen H, Koistinen R, Milgrom E (Aug 2002). "Glycodelin: a major lipocalin protein of the reproductive axis with diverse actions in cell recognition and differentiation". Endocrine Reviews. 23 (4): 401–30. doi:10.1210/er.2001-0026. PMID 12202458.
- Seppälä M, Koistinen H, Koistinen R, Chiu PC, Yeung WS (2007). "Glycosylation related actions of glycodelin: gamete, cumulus cell, immune cell and clinical associations". Human Reproduction Update. 13 (3): 275–87. doi:10.1093/humupd/dmm004. PMID 17329396.
- Garde J, Bell SC, Eperon IC (Mar 1991). "Multiple forms of mRNA encoding human pregnancy-associated endometrial alpha 2-globulin, a beta-lactoglobulin homologue". Proceedings of the National Academy of Sciences of the United States of America. 88 (6): 2456–60. Bibcode:1991PNAS...88.2456G. doi:10.1073/pnas.88.6.2456. PMC 51251. PMID 2006183.
- Wood PL, Iffland CA, Allen E, Bentick B, Burton P, Shaw RW, Bell SC (May 1990). "Serum levels of pregnancy-associated endometrial alpha 2-globulin (alpha 2-PEG), a glycosylated beta-lactoglobulin homologue, in successful and unsuccessful assisted conception". Human Reproduction. 5 (4): 421–6. doi:10.1093/oxfordjournals.humrep.a137115. PMID 2113930.
- Vaisse C, Atger M, Potier B, Milgrom E (1990). "Human placental protein 14 gene: sequence and characterization of a short duplication". DNA and Cell Biology. 9 (6): 401–13. doi:10.1089/dna.1990.9.401. PMID 2206398.
- Check JH, Nowroozi K, Chase JS, Vaze M, Joshi S, Baker AF (Jun 1990). "Serum progestagen-associated endometrial protein (PEP) levels in conception versus nonconception cycles following in vitro fertilization-embryo transfer". Journal of in Vitro Fertilization and Embryo Transfer. 7 (3): 134–6. doi:10.1007/BF01135675. PMID 2380618. S2CID 12383913.
- Wood PL, Waites GT, MacVicar J, Davidson AC, Walker RA, Bell SC (Dec 1988). "Immunohistological localization of pregnancy-associated endometrial alpha 2-globulin (alpha 2-PEG) in endometrial adenocarcinoma and effect of medroxyprogesterone acetate". British Journal of Obstetrics and Gynaecology. 95 (12): 1292–8. doi:10.1111/j.1471-0528.1988.tb06820.x. PMID 2975952. S2CID 71096539.
- Joshi SG (1987). "Progestin-Dependent Human Endometrial Protein: A Marker for Monitoring Human Endometrial Function". Cell and Molecular Biology of the Uterus. Advances in Experimental Medicine and Biology. Vol. 230. pp. 167–86. doi:10.1007/978-1-4684-1297-0_10. ISBN 978-1-4684-1299-4. PMID 3135704.
- Julkunen M, Seppälä M, Jänne OA (Dec 1988). "Complete amino acid sequence of human placental protein 14: a progesterone-regulated uterine protein homologous to beta-lactoglobulins". Proceedings of the National Academy of Sciences of the United States of America. 85 (23): 8845–9. Bibcode:1988PNAS...85.8845J. doi:10.1073/pnas.85.23.8845. PMC 282603. PMID 3194393.
- Huhtala ML, Seppälä M, Närvänen A, Palomäki P, Julkunen M, Bohn H (Jun 1987). "Amino acid sequence homology between human placental protein 14 and beta-lactoglobulins from various species". Endocrinology. 120 (6): 2620–2. doi:10.1210/endo-120-6-2620. PMID 3569148.
- Bell SC, Keyte JW, Waites GT (Nov 1987). "Pregnancy-associated endometrial alpha 2-globulin, the major secretory protein of the luteal phase and first trimester pregnancy endometrium, is not glycosylated prolactin but related to beta-lactoglobulins". The Journal of Clinical Endocrinology and Metabolism. 65 (5): 1067–71. doi:10.1210/jcem-65-5-1067. PMID 3667877.
- Bell SC, Hales MW, Patel SR, Kirwan PH, Drife JO, Milford-Ward A (Sep 1986). "Amniotic fluid concentrations of secreted pregnancy-associated endometrial alpha 1- and alpha 2-globulins (alpha 1- and alpha 2-PEG)". British Journal of Obstetrics and Gynaecology. 93 (9): 909–15. doi:10.1111/j.1471-0528.1986.tb08007.x. PMID 3768286. S2CID 70522186.
- Joshi SG, Smith RA, Stokes DK (Nov 1980). "A progestagen-dependent endometrial protein in human amniotic fluid". Journal of Reproduction and Fertility. 60 (2): 317–21. doi:10.1530/jrf.0.0600317. PMID 6776278.
- Horne CH, Paterson WF, Sutcliffe RG (Jul 1982). "Localization of alpha-uterine protein in human endometrium". Journal of Reproduction and Fertility. 65 (2): 447–50. doi:10.1530/jrf.0.0650447. PMID 7047733.