View source for LYPD6B

{{Short description|Protein-coding gene in the species Homo sapiens}}
{{Infobox gene}}
'''LY6/PLAUR Domain Containing 6B''', also known under the name '''Cancer/Testis Antigen 116''' ('''CTA116''') and '''LYPD7''' is encoded by the ''LYPD6B'' [[gene]].<ref name="entrez">{{cite web| title = Entrez Gene: LY6/PLAUR domain containing 6B|url=https://www.ncbi.nlm.nih.gov/gene/130576|publisher=[[National Center for Biotechnology Information|NCBI]]|access-date=21 July 2020}}</ref> LYPD6B is a member of the [[LY6|lymphocyte antigen 6 (LY6)]] protein family. It is expressed in the [[testis]], [[lung]]s, [[stomach]], [[prostate]] and in the [[nervous system]] where it acts as a modulator of [[nicotinic acetylcholine receptor]] (nAChRs) activity.
==Structure==
The protein is 183 [[amino acid]]s long and its [[molecular mass]] is 20.656.<ref name="UniProt">{{cite web|url=http://www.uniprot.org/uniprot/Q8NI32#sequences|title=UniProt, Q8NI32|access-date=23 July 2020}}</ref> The gene ''LYPD6B'' encoding the protein is located on [[chromosome 2]] in humans.
As a member of the Ly-6/uPAR family, the protein contains a [[disulfide]] β-structural core and three protruding loops.<ref name="kulbatskii" />
==Background==
The protein was discovered for the first time in a 2009 study; its presence was detected in the [[cytoplasm]] and it was associated with activation of [[AP-1 transcription factor|the AP-1 transcription factor]].<ref>{{cite journal | vauthors = Ni J, Lang Q, Bai M, Zhong C, Chen X, Wan B, Yu L | title = Cloning and characterization of a human LYPD7, a new member of the Ly-6 superfamily | journal = [[Molecular Biology Reports]] | volume = 45 | issue = 11 | pages = 697–703 | date = April 2009 | doi = 10.1007/s11033-008-9231-6| pmid = 18360792 | s2cid = 1772973 }}</ref> LYPD6B is known as a prototoxin due to its structural similarity with the 3-fingered snake venom proteins [[α-bungarotoxin]] and [[cobratoxin]].<ref name="FASEB">{{cite journal | vauthors = Ochoa V, George AA, Nishi R, Whiteaker P | title = The prototoxin LYPD6B modulates heteromeric α3β4-containing nicotinic acetylcholine receptors, but not α7 homomers | journal = FASEB Journal | volume = 30 | issue = 3 | pages = 1109–19 | date = March 2016 | pmid = 26586467 | pmc = 4750422 | doi = 10.1096/fj.15-274548 | doi-access = free }}</ref> As a prototoxin, LYPD6B also belongs to the [[protein family]] of [[LY6|Ly-6/urokinase plasminogen activator receptor]] (Ly6/uPAR). It has a 3-fingered motif [[secondary structure]] which appears due to the presence of 8–10 [[cysteine]] residues that facilitate [[disulfide bond]] formation.<ref name="FASEB" />
==Role==
The protein is expressed in the [[nervous system]] where it acts as an enhancer of the activity of the [[neurotransmitter]] [[acetylcholine]] certain [[nicotinic acetylcholine receptor|α7-containing nicotinic acetylcholine receptors]], which have a role in learning.<ref name="FASEB" /> A duplication of the gene has been detected in a [[case study]] of two individuals with severe intellectual disability, suggesting its role in proper brain development and [[cognitive function]].<ref>{{cite journal | vauthors = Chung BH, Mullegama S, Marshall CR, Lionel AC, Weksberg R, Dupuis L, Brick L, Li C, Scherer SW, Aradhya S, Stavropoulos DJ, Elsea SH, Mendoza-Londono R | display-authors = 6 | title = Severe intellectual disability and autistic features associated with microduplication 2q23.1 | journal = European Journal of Human Genetics | volume = 20 | issue = 4 | pages = 398–403 | date = April 2012 | pmid = 22085900 | pmc = 3306850 | doi = 10.1038/ejhg.2011.199 }}</ref> Additionally, the protein demonstrates high expression in several other normal organs including the [[testis]], [[lung]]s, [[stomach]], and [[prostate]].<ref>{{cite journal | vauthors = Kong HK, Park JH
| title = Characterization and function of human Ly-6/uPAR molecules | journal = BMB Reports | volume = 45 | issue = 11 | pages = 595–603 | date = November 2012 | pmc = 4133805| doi = 10.5483/bmbrep.2012.45.11.210 | pmid = 23186997 }}</ref>
[[Hypermethylation]] of the gene and a subsequent decreased expression has been demonstrated as one of the contributors to the invasive capacity of cancer cells in [[melanoma]].<ref>{{cite journal | vauthors = Koroknai V, Szász I, Hernandez-Vargas H, Fernandez-Jimenez N, Cuenin C, Herceg Z, Vízkeleti L, Ádány R, Ecsedi S, Balázs M | display-authors = 6 | title = DNA hypermethylation is associated with invasive phenotype of malignant melanoma | journal = Experimental Dermatology | volume = 29 | issue = 1 | pages = 39–50 | date = January 2020 | pmid = 31602702 | doi = 10.1111/exd.14047 | doi-access = free | hdl = 2437/278321 | hdl-access = free }}</ref>
The protein LYPD6 also leads to an increase in [[Wnt signaling pathway|Wnt]]/[[β-catenin]] signaling.<ref name="kulbatskii">{{cite journal|first1=Dmitrii|last1=Kulbatskii|first2=Zakhar|last2=Shenkarev|first3=Maxim|last3=Bychkov|first4=Eugene|last4=Loktyushov|first5=Mikhail|last5=Shulepko|first6=Sergey|last6=Koshelev|first7=Igor|last7=Povarov|first8=Alexander|last8=Popov|first9=Steve|last9=Peigneur|first10=Anton|last10=Chugunov|title=Human Three-Finger Protein Lypd6 Is a Negative Modulator of the Cholinergic System in the Brain|journal=Front Cell Dev Biol|date=21 September 2021|issue=21|volume=9|page=662227 |doi=10.3389/fcell.2021.662227|pmc=8494132|pmid=34631692|doi-access=free }}</ref>
== References ==
{{reflist}}
[[Category:Human proteins]]
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