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TYRP1 is a globular monomeric protein. It is composed of several domains: a short peptide signal on the N-terminal side followed by a large intra-melanosomal domain. This intra-melanosomal domain contain a cystein-rich domain and a catalytic tyrosinase-like subdomain with two ion-binding sites.<ref name="Xlai">[Xuelei Lai, Harry J. Wichers, Montserrat Soler‐Lopez, Bauke W. Dijkstra. Structure and Function of Human Tyrosinase and Tyrosinase‐Related Proteins. 2018 Jan 2 Epub 2017 Nov 28 PMID: 29052256 https://www.ncbi.nlm.nih.gov/pubmed/29052256 DOI: 10.1002/chem.201704410 https://onlinelibrary.wiley.com/doi/abs/10.1002/chem.201704410]</ref> The next part of the sequence is composed of a transmembrane alpha helix followed by a short cytoplasmic sequence on the C-terminal chain. <ref name = "decker"> [Decker. H, Tuczek.F. The Recent Crystal Structure of Human Tyrosinase Related Protein 1 (HsTYRP1) Solves an Old Problem and Poses a New One. 2017 Nov 13. Epub 2017 Oct 9 PMID: 28990327 https://www.ncbi.nlm.nih.gov/pubmed/28990327 DOI: 10.1002/anie.201708214 https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.201708214]</ref>

The cystein-rich domain has an epidermal growth factor‐like fold formed by two pairs of short antiparallel beta-strands (62-66/98-102 and 116-118/124-126)<ref name= "lai"/> . This previous domain strongly interact with the tyrosinase-like subdomain by the lastloop of the cystein-rich domain preceding the N-terminal domain. The role of the cystein-rich domain is still unknown, it is only found in mammalians. This domain is stabilized by three (42-65/56-99/101-110) disulfide bounds and is located at the opposite of the active site. It is said that the cystein-rich domain might help to the formation of a complexe between TYR and TYRP2.<ref name="Xlai"/><ref name= "lai"/>  

It is composed of four helix bundle connected by long loops and stabilized by two disulfide bonds(C258–C261 and C290–C303). This domain interacts with cystein-rich domain by three insertions located on the same side of tyrosinase-like subdomain (residues 155–182, 199–204, and 291–300)<ref name= "lai"/>  

TYRP1 has six sites of N-glygosylation which are important for maturation of the protein (Asn 96, 104,181,304,350,385). On our 3D structure all these sites are glycosylated.  

    

=== The active site ===  

The active site is located in the tyrosinase-like subdomain. It is delimited by four helices and contains the binuclear metal-binding site. It looks like type-3 binuclear copper-binding site of Tyrosinases. The two ions are bound with planar trigonal geometry and the distance between them is : 3,5 ± 0,1 Ā. A molecule of water located at the same distance (2,1 ± 0,1 Ā) from the two ions can make a bridge between them. Mutations on amino acids of the active site have no significant affect on TYRP1 activity.<ref name= "lai"/>  

The crystal structure of TYRP1 shows that TYRP1 can bind tyrosine, mimosine (DOPA equivalent), kojic acid, tropolone. DOPA and tyrosine can interact with the active site by their aromatic hydroxy or keto groups through hydrogen bounds with water molecule between the ions. Aromatic stacking interactions with H381 and hydrogen bonds between carboxylate group, ARG374 and Ser 394 represent other interactions between these substrates and the active site. Tropolone have direct interactions with one of the Zn2+ ion because  of its metal-chelating property. The interactions between tropolone and Zn2+ show that the binuclear site is flexible. The ring hydroxy and keto groups of kojic acid bind the Zinc ion away from 3Ā. All these non specific interactions may confirm that TYRP1 can have several roles.<ref name= "lai"/>