マンノース結合タンパク質

関: mannose-binding lectin

WordNet

executed with proper legal authority; "a binding contract"
the protective covering on the front, back, and spine of a book; "the book had a leather binding" (同)book binding, cover, back
strip sewn over or along an edge for reinforcement or decoration
the capacity to attract and hold something
any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes; "a diet high in protein"

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義務的な,拘束力ある / 〈U〉しばること;〈C〉しばる物 / 〈C〉製本,装丁 / 〈U〉縁(‘ふち')取り材料
蛋白(たんばく)質

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/09/27 20:18:38」(JST)

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Mannose-binding lectin (MBL), also called mannose-binding protein or mannan-binding protein (MBP), is a lectin that is instrumental in innate immunity.^[1]^[2]

Structure

MBL has an oligomeric structure (400-700 kDa), built of subunits that contain three presumably identical peptide chains of about 30 kDa each.

Although MBL can form several oligomeric forms, there are indications that dimers and trimers are not biologically active and at least a tetramer form is needed for activation of complement.^[3]

Genes and polymorphisms

Human MBL2 gene is located on chromosome 10q11.2-q21.^[4] Mice have two homologous genes, but in human the first of them was lost. A low level expression of an MBL1 pseudogene 1 (MBL1P1) was detected in liver. The pseudogene encodes a truncated 51-amino acid protein that is homologous to the MBLA isoform in rodents and some primates.^[5]

Structural mutations in exon 1 of the human MBL2 gene, at codon 52 (Arg to Cys, allele D), codon 54 (Gly to Asp, allele B) and codon 57 (Gly to Glu, allele C), also independently reduce the level of functional serum MBL by disrupting the collagenous structure of the protein.^[6] Furthermore, several nucleotide substitutions in the promoter region of the MBL2 gene at position −550 (H/L polymorphism), −221 (X/Y polymorphism) and −427, −349, −336, del (−324 to −329), −70 and +4 (P/Q polymorphisms) affect the MBL serum concentration. Both the frequency of structural mutations and the promoter polymorphisms that are in strong linkage disequilibrium vary among ethnic groups resulting in seven major haplotypes: HYPA, LYQA, LYPA, LXPA, LYPB, LYQC and HYPD. Differences in the distribution of these haplotypes are the major cause of interracial variations in MBL serum levels. Both HYPA and LYQA are high-producing haplotypes, LYPA intermediate-producing haplotype and LXPA low-producing haplotype, whereas LYPB, LYQC and HYPD are defective haplotypes, which cause a severe MBL deficiency.^[7]

Both MBL2 and MBL1P1 genes has been repeatedly hit throughout evolution of primates. The latter silenced eventually by mutations in the glycine residues of the collagen-like region. It has been selectively turned off during evolution through the same molecular mechanisms causing the MBL2 variant alleles in man, suggesting an evolutionary selection for low-producing MBL genes.^[6]

Posttranslational modifications

In rat hepatocytes, MBL is synthesized in the rough endoplasmic reticulum. While in Golgi, it undergoes two distinct posttranslational modifications and is assembled into high molecular weight multimeric complexes. The modifications produce MBL in multiple forms of slightly various molecular masses and pI from 5.7 to 6.2.^[8] Proteolytic cleavage also resulted in removal of the 20-aa N-terminal signal peptide,^[9] and hydroxylation and glycosylation were also detected.^[8] Some cysteine residues can be converted to dehydroalanin.^[10]

Function

MBL belongs to the class of collectins in the C-type lectin superfamily, whose function appears to be pattern recognition in the first line of defense in the pre-immune host. MBL recognizes carbohydrate patterns, found on the surface of a large number of pathogenic micro-organisms, including bacteria, viruses, protozoa and fungi. Binding of MBL to a micro-organism results in activation of the lectin pathway of the complement system.

Another important function of MBL is that this molecule binds senescent^[11] and apoptotic cells and enhances engulfment of whole, intact apoptotic cells, as well as cell debris by phagocytes.^[12]^[13]

Activation

The complement system can be activated through three pathways: the classical pathway, the alternative pathway, and the lectin pathway. One way that the most-recently discovered lectin pathway is activated is through mannose-binding lectin protein. MBL binds to carbohydrates (to be specific, D-mannose and L-fucose residues) found on the surfaces of many pathogens.

For example, MBL has been shown to bind to:

yeasts such as Candida albicans^[14]
viruses such as HIV^[15] and influenza A
many bacteria, including Salmonella and Streptococci
parasites like Leishmania

Complexes

MBL in the blood is complexed with (bound to) another protein, a serine protease called MASP (MBL-associated serine protease). There are three MASPs: MASP-1, MASP-2 and MASP-3, which have protease domains. There are also sMAP (also called MAp19) and MAp44, which do not have protease domains and are thought to be regulatory molecules of MASPs. MASPs also form complexes with ficolins, which are similar to MBL functionally and structurally with the exception that ficolins recognize their targets through fibrinogen-like domains, unlike MBL.

In order to activate the complement system when MBL binds to its target (for example, mannose on the surface of a bacterium), the MASP protein functions to cleave the blood protein C4 into C4a and C4b. The C4b fragments can then bind to the surface of the bacterium, and initiate the formation of a C3-convertase.

The subsequent complement cascade catalyzed by C3-convertase results in creating a membrane attack complex, which causes lysis of the pathogen as well as altered-self in the context of apoptotic and necrotic cells.

MBL/MASP-1 complex also has thrombin-like activity (thrombin clots fibrin to initiate blood clots). Mice that genetically lack MBL or MASP-1/3 (but not MASP-2/sMAP) have prolonged bleeding time in experimental injury models, although mice are seen to be normal if there is no insult to the body.

Clinical significance

It is produced in the liver as a response to infection, and is part of many other factors termed acute phase proteins.^[16] Expression and function in other organs were also suggested.^[17] The three structural polymorphisms of exon 1 have been reported to cause susceptibility to various common infections, including meningococcal disease.^[18]^[19] However, evidence has been presented that suggests no harmful effect of these variants with regard to mengingococcal disease.^[20]

External links

Mannan-Binding Lectin at the US National Library of Medicine Medical Subject Headings (MeSH)

References

^ Fraser IP, Koziel H, Ezekowitz RA (1998). "The serum mannose-binding protein and the macrophage mannose receptor are pattern recognition molecules that link innate and adaptive immunity.". Semin. Immunol. 10 (5): 363–72. doi:10.1006/smim.1998.0141. PMID 9799711.
^ Worthley DL, Bardy PG, Mullighan CG (2005). "Mannose-binding lectin: biology and clinical implications.". Internal medicine journal 35 (9): 548–55. doi:10.1111/j.1445-5994.2005.00908.x. PMID 16105157.
^ Sheriff S, Chang CY, Ezekowitz RA (November 1994). "Human mannose-binding protein carbohydrate recognition domain trimerizes through a triple alpha-helical coiled-coil". Nat. Struct. Biol. 1 (11): 789–94. doi:10.1038/nsb1194-789. PMID 7634089.
^ Sastry K, Herman GA, Day L, Deignan E, Bruns G, Morton CC, Ezekowitz RA (October 1989). "The human mannose-binding protein gene. Exon structure reveals its evolutionary relationship to a human pulmonary surfactant gene and localization to chromosome 10". J. Exp. Med. 170 (4): 1175–89. doi:10.1084/jem.170.4.1175. PMC 2189467. PMID 2477486.
^ Guo N, Mogues T, Weremowicz S, Morton CC, Sastry KN (March 1998). "The human ortholog of rhesus mannose-binding protein-A gene is an expressed pseudogene that localizes to chromosome 10". Mamm. Genome 9 (3): 246–9. doi:10.1007/s003359900735. PMID 9501312.
^ ^a ^b Seyfarth J, Garred P, Madsen HO (2005). "The ‘involution’ of mannose-binding lectin". Human Molecular Genetics 14 (19): 2859–69. doi:10.1093/hmg/ddi318. PMID 16115813.
^ Online 'Mendelian Inheritance in Man' (OMIM) mannose-binding protein deficiency -614372
^ ^a ^b Colley KJ, Baenziger JU (1987). "Identification of the posttranslational modifications of the core-specific lectin. The core-specific lectin contains hydroxyproline, hydroxylysine, and glucosylgalactosylhydroxylysine residues". J Biol Chem. 262 (21): 10290–5. PMID 3611062.
^ "Mannose-binding protein C precursor [Homo sapiens]". Retrieved 2012-01-03.
^ Jensen PH, Laursen I, Matthiesen F, Højrup P (2007). "Posttranslational modifications in human plasma MBL and human recombinant MBL". Biochim. Biophys. Acta - Proteins & Proteomics. 1774: 335–44. doi:10.1016/j.bbapap.2006.12.008.
^ Tomaiuolo R, Ruocco A, Salapete C, Carru C, Baggio G, Franceschi C, Zinellu A, Vaupel J, Bellia C, Lo Sasso B, Ciaccio M, Castaldo G, Deiana L (March 2012). "Activity of mannose-binding lectin (MBL) in centenarians". Aging Cell. 11 (3): 394–400. doi:10.1111/j.1474-9726.2012.00793.x. PMID 22239660.
^ Ogden CA, deCathelineau A, Hoffmann PR, Bratton D, Ghebrehiwet B, Fadok VA, Henson PM (September 2001). "C1q and mannose binding lectin engagement of cell surface calreticulin and CD91 initiates macropinocytosis and uptake of apoptotic cells". J. Exp. Med. 194 (6): 781–95. doi:10.1084/jem.194.6.781. PMC 2195958. PMID 11560994.
^ Stuart LM, Takahashi K, Shi L, Savill J, Ezekowitz RA (March 2005). "Mannose-binding lectin-deficient mice display defective apoptotic cell clearance but no autoimmune phenotype". J. Immunol. 174 (6): 3220–6. doi:10.4049/jimmunol.174.6.3220. PMID 15749852.
^ de Jong MA, Vriend LE, Theelen B, Taylor ME, Fluitsma D, Boekhout T, Geijtenbeek TB (March 2010). "C-type lectin Langerin is a beta-glucan receptor on human Langerhans cells that recognizes opportunistic and pathogenic fungi". Mol. Immunol. 47 (6): 1216–25. doi:10.1016/j.molimm.2009.12.016. PMC 2837148. PMID 20097424.
^ Ji X, Gewurz H, Spear GT (February 2005). "Mannose binding lectin (MBL) and HIV". Mol. Immunol. 42 (2): 145–52. doi:10.1016/j.molimm.2004.06.015. PMID 15488604.
^ Herpers, B L; Endeman, H; de Jong, B A W; de Jongh, B M; Grutters, J C; Biesma, D H; vam Velzen-Blad, H (Jun 2009). "Acute-phase responsiveness of mannose-binding lectin in community-acquired pneumonia is highly dependent upon MBL2 genotypes". Clin Exp Immunol 156 (3): 488–94. doi:10.1111/j.1365-2249.2009.03929.x. PMC 2691978. PMID 19438602.
^ Worthley DL, Bardy PG, Gordon DL, Mullighan CG (October 2006). "Mannose-binding lectin and maladies of the bowel and liver". World J. Gastroenterol. 12 (40): 6420–8. PMID 17072973.
^ Hibberd, M. L.; Sumiya, M.; Summerfield, J. A.; Booy, R.; Levin, M. (1999). "Association of variants of the gene for mannose-binding lectin with susceptibility to meningococcal disease". The Lancet 353 (9158): 1049. doi:10.1016/S0140-6736(98)08350-0.
^ Faber, J.; Schuessler, T.; Finn, A.; Murdoch, C.; Zenz, W.; Habermehl, P.; Meyer, C. U.; Zabel, B. U.; Schmitt, H. J.; Zepp, F.; Knuf, M. (2007). "Age-Dependent Association of Human Mannose-Binding Lectin Mutations with Susceptibility to Invasive Meningococcal Disease in Childhood". The Pediatric Infectious Disease Journal 26 (3): 243–246. doi:10.1097/01.inf.0000256751.76218.7c. PMID 17484222.
^ Bradley, D. T.; Bourke, T. W.; Fairley, D. J.; Borrow, R.; Shields, M. D.; Young, I. S.; Zipfel, P. F.; Hughes, A. E. (2012). "Genetic susceptibility to invasive meningococcal disease: MBL2 structural polymorphisms revisited in a large case-control study and a systematic review". International Journal of Immunogenetics: no. doi:10.1111/j.1744-313X.2012.01095.x.

UpToDate Contents

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1. マンノース結合レクチン欠損症 mannose binding lectin deficiency
2. マンノース結合レクチン mannose binding lectin
3. 補体系の概要および臨床的評価 overview and clinical assessment of the complement system
4. 補体系の遺伝性疾患 inherited disorders of the complement system
5. 感染症を繰り返す成人に対するアプローチ approach to the adult with recurrent infections

English Journal

Three novel B-type mannose-specific lectins of Cynoglossus semilaevis possess varied antibacterial activities against Gram-negative and Gram-positive bacteria.

Sun YY1, Liu L1, Li J2, Sun L3.
Developmental and comparative immunology.Dev Comp Immunol.2016 Feb;55:194-202. doi: 10.1016/j.dci.2015.10.003. Epub 2015 Oct 9.
Lectins are a group of sugar-binding proteins that are important factors of the innate immune system. In this study, we examined, in a comparative manner, the expression and function of three Bulb-type (B-type) mannose-specific lectins (named CsBML1, CsBML2, and CsBML3) from tongue sole. All three l
PMID 26455466

Mannose-binding lectin (MBL) insufficiency protects against the development of systemic inflammatory response after pediatric cardiac surgery.

Pągowska-Klimek I1, Świerzko AS2, Michalski M2, Moll M3, Szala-Poździej A2, Sokołowska A2, Krajewski WR1, Cedzyński M4.
Immunobiology.Immunobiology.2016 Feb;221(2):175-81. doi: 10.1016/j.imbio.2015.09.010. Epub 2015 Sep 8.
We investigated MBL2 and MASP2 genotypes, serum MBL (mannose-binding lectin) levels and activities of its complexes with associated serine proteases (MASP-1, MASP -2), in relation to complications following cardiac surgery in 195 children. The incidence of SIRS was lower in patients carrying MBL2 A/
PMID 26382056

Using environmental proteomics to assess pollutant response of Carcinus maenas along the Tunisian coast.

Ghedira J1, Chicano-Gálvez E2, Fernández-Cisnal R2, Jebali J1, Banni M1, Chouba L3, Boussetta H1, López-Barea J4, Alhama J2.
The Science of the total environment.Sci Total Environ.2016 Jan 15;541:109-18. doi: 10.1016/j.scitotenv.2015.09.032. Epub 2015 Sep 22.
Biochemical responses to pollutants were studied at four Tunisia littoral sites using Carcinus maenas as a bioindicator. Proteomic analysis was used to assess the global impact of complex pollution mixtures, and to provide new biomarkers and basic insights into pollutant toxicity. Metal contents and
PMID 26402481

Japanese Journal

Isolation and Biochemical Characterization of Mucus Proteins in Japanese Bunching Onion (Allium fistulosum) Green Leaves

Food Science and Technology Research 22(2), 235-243, 2016
NAID 130005147061

Dioscorea japonica Thunb.由来DJ1タンパク質のクローニングと大腸菌による発現と精製

応用糖質科学 : 日本応用糖質科学会誌 4(3), 241-248, 2014-08-20
NAID 110009843535

Dioscorea japonica Thunb.で高生産されYam Viscous Polysaccharide(YVP)画分に含まれるDJ1βタンパク質の精製

応用糖質科学 : 日本応用糖質科学会誌 4(2), 167-172, 2014-05-20
NAID 110009823327

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★リンクテーブル★

リンク元	「マンノース結合タンパク質」
拡張検索	「mannose-binding protein-associated serine protease」
関連記事	「binding」「binding protein」「mannose」

「マンノース結合タンパク質」

Mannose-binding lectin (protein C) 2, soluble
	PDB rendering based on 1hup.
Available structures
PDB	Ortholog search: PDBe, RCSB
List of PDB id codes
	1HUP
Identifiers
Symbols	MBL2 ; COLEC1; HSMBPC; MBL; MBL2D; MBP; MBP-C; MBP1; MBPD
External IDs	OMIM: 154545 MGI: 96924 HomoloGene: 110436 ChEMBL: 1795113 GeneCards: MBL2 Gene
Gene ontology
Molecular function	• receptor binding; • calcium ion binding; • protein binding; • mannose binding; • calcium-dependent protein binding;
Cellular component	• extracellular region; • collagen trimer; • extracellular space; • cell surface;
Biological process	• complement activation, lectin pathway; • acute-phase response; • complement activation; • complement activation, classical pathway; • response to oxidative stress; • opsonization; • defense response to bacterium; • negative regulation of growth of symbiont in host; • innate immune response; • negative regulation of viral process; • positive regulation of phagocytosis; • defense response to Gram-positive bacterium; • killing by host of symbiont cells;
	Sources: Amigo / QuickGO
RNA expression pattern
	More reference expression data
Orthologs
	v; t; e;

　　[★]

英: mannose-binding protein, MBP
関: マンノース結合レクチン

[show details]

マンノース結合蛋白質 : 47 件
マンノース結合蛋白 : 51 件
マンノース結合タンパク質 : 79 件
マンノース結合タンパク : 30 件

「mannose-binding protein-associated serine protease」

　　[★]

マンノース結合タンパク質関連セリンプロテアーゼ

関: MASP、MBP-associated serine protease

「binding」

　　[★]

n.

結合、バインディング

adj.

結合性の

関: affinity、associate、bind、bond、bonding、combine、conjoin、conjugate、conjugation、conjunction、connect、connection、connective、connectivity、couple、dock、engage、engagement、join、ligate、linkage、symphysial、symphysic、union

「binding protein」

　　[★]

結合タンパク質、結合タンパク、結合蛋白質、結合蛋白

関: BP、carrier protein、transport protein

「mannose」

　　[★]

マンノース

関: D-mannose

[1] Fraser IP, Koziel H, Ezekowitz RA (1998). "The serum mannose-binding protein and the macrophage mannose receptor are pattern recognition molecules that link innate and adaptive immunity.". Semin. Immunol. 10 (5): 363–72. doi:10.1006/smim.1998.0141. PMID 9799711.

[2] Worthley DL, Bardy PG, Mullighan CG (2005). "Mannose-binding lectin: biology and clinical implications.". Internal medicine journal 35 (9): 548–55. doi:10.1111/j.1445-5994.2005.00908.x. PMID 16105157.

[pmid7634089-3] Sheriff S, Chang CY, Ezekowitz RA (November 1994). "Human mannose-binding protein carbohydrate recognition domain trimerizes through a triple alpha-helical coiled-coil". Nat. Struct. Biol. 1 (11): 789–94. doi:10.1038/nsb1194-789. PMID 7634089.

[pmid2477486-4] Sastry K, Herman GA, Day L, Deignan E, Bruns G, Morton CC, Ezekowitz RA (October 1989). "The human mannose-binding protein gene. Exon structure reveals its evolutionary relationship to a human pulmonary surfactant gene and localization to chromosome 10". J. Exp. Med. 170 (4): 1175–89. doi:10.1084/jem.170.4.1175. PMC 2189467. PMID 2477486.

[pmid9501312-5] Guo N, Mogues T, Weremowicz S, Morton CC, Sastry KN (March 1998). "The human ortholog of rhesus mannose-binding protein-A gene is an expressed pseudogene that localizes to chromosome 10". Mamm. Genome 9 (3): 246–9. doi:10.1007/s003359900735. PMID 9501312.

[Seyfarth-6] Seyfarth J, Garred P, Madsen HO (2005). "The ‘involution’ of mannose-binding lectin". Human Molecular Genetics 14 (19): 2859–69. doi:10.1093/hmg/ddi318. PMID 16115813.

[OMIM_614372-7] Online 'Mendelian Inheritance in Man' (OMIM) mannose-binding protein deficiency -614372

[Colley-8] Colley KJ, Baenziger JU (1987). "Identification of the posttranslational modifications of the core-specific lectin. The core-specific lectin contains hydroxyproline, hydroxylysine, and glucosylgalactosylhydroxylysine residues". J Biol Chem. 262 (21): 10290–5. PMID 3611062.

[9] "Mannose-binding protein C precursor [Homo sapiens]". Retrieved 2012-01-03.

[10] Jensen PH, Laursen I, Matthiesen F, Højrup P (2007). "Posttranslational modifications in human plasma MBL and human recombinant MBL". Biochim. Biophys. Acta - Proteins & Proteomics. 1774: 335–44. doi:10.1016/j.bbapap.2006.12.008.

[11] Tomaiuolo R, Ruocco A, Salapete C, Carru C, Baggio G, Franceschi C, Zinellu A, Vaupel J, Bellia C, Lo Sasso B, Ciaccio M, Castaldo G, Deiana L (March 2012). "Activity of mannose-binding lectin (MBL) in centenarians". Aging Cell. 11 (3): 394–400. doi:10.1111/j.1474-9726.2012.00793.x. PMID 22239660.

[pmid11560994-12] Ogden CA, deCathelineau A, Hoffmann PR, Bratton D, Ghebrehiwet B, Fadok VA, Henson PM (September 2001). "C1q and mannose binding lectin engagement of cell surface calreticulin and CD91 initiates macropinocytosis and uptake of apoptotic cells". J. Exp. Med. 194 (6): 781–95. doi:10.1084/jem.194.6.781. PMC 2195958. PMID 11560994.

[pmid15749852-13] Stuart LM, Takahashi K, Shi L, Savill J, Ezekowitz RA (March 2005). "Mannose-binding lectin-deficient mice display defective apoptotic cell clearance but no autoimmune phenotype". J. Immunol. 174 (6): 3220–6. doi:10.4049/jimmunol.174.6.3220. PMID 15749852.

[pmid20097424-14] Jong MA, Vriend LE, Theelen B, Taylor ME, Fluitsma D, Boekhout T, Geijtenbeek TB (March 2010). "C-type lectin Langerin is a beta-glucan receptor on human Langerhans cells that recognizes opportunistic and pathogenic fungi". Mol. Immunol. 47 (6): 1216–25. doi:10.1016/j.molimm.2009.12.016. PMC 2837148. PMID 20097424.

[pmid15488604-15] Ji X, Gewurz H, Spear GT (February 2005). "Mannose binding lectin (MBL) and HIV". Mol. Immunol. 42 (2): 145–52. doi:10.1016/j.molimm.2004.06.015. PMID 15488604.

[16] Herpers, B L; Endeman, H; de Jong, B A W; de Jongh, B M; Grutters, J C; Biesma, D H; vam Velzen-Blad, H (Jun 2009). "Acute-phase responsiveness of mannose-binding lectin in community-acquired pneumonia is highly dependent upon MBL2 genotypes". Clin Exp Immunol 156 (3): 488–94. doi:10.1111/j.1365-2249.2009.03929.x. PMC 2691978. PMID 19438602.

[pmid17072973-17] Worthley DL, Bardy PG, Gordon DL, Mullighan CG (October 2006). "Mannose-binding lectin and maladies of the bowel and liver". World J. Gastroenterol. 12 (40): 6420–8. PMID 17072973.

[HibberdML1999-18] Hibberd, M. L.; Sumiya, M.; Summerfield, J. A.; Booy, R.; Levin, M. (1999). "Association of variants of the gene for mannose-binding lectin with susceptibility to meningococcal disease". The Lancet 353 (9158): 1049. doi:10.1016/S0140-6736(98)08350-0.

[FaberK2007-19] Faber, J.; Schuessler, T.; Finn, A.; Murdoch, C.; Zenz, W.; Habermehl, P.; Meyer, C. U.; Zabel, B. U.; Schmitt, H. J.; Zepp, F.; Knuf, M. (2007). "Age-Dependent Association of Human Mannose-Binding Lectin Mutations with Susceptibility to Invasive Meningococcal Disease in Childhood". The Pediatric Infectious Disease Journal 26 (3): 243–246. doi:10.1097/01.inf.0000256751.76218.7c. PMID 17484222.

[BradleyDT2012-20] Bradley, D. T.; Bourke, T. W.; Fairley, D. J.; Borrow, R.; Shields, M. D.; Young, I. S.; Zipfel, P. F.; Hughes, A. E. (2012). "Genetic susceptibility to invasive meningococcal disease: MBL2 structural polymorphisms revisited in a large case-control study and a systematic review". International Journal of Immunogenetics: no. doi:10.1111/j.1744-313X.2012.01095.x.

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mannose-binding protein