Details for: MYO18B

Gene ID: 84700

Gene Type:  Protein-coding  - A gene that serves as a template for producing a messenger RNA (mRNA) molecule, which is then translated into a functional protein.

Symbol: MYO18B

Ensembl ID: ENSG00000133454

Description: myosin XVIIIB

Cell Significance Landscape

Associated with

Significant Cells

Cell Significance Index (CSI) scores for the chosen context(s)

  • cardiac muscle cell CL0000746
    CSI 10.16
    rCSI 14.58%
    PRS 98.16
  • erythrocyte CL0000232
    CSI 9.56
    rCSI 21.7%
    PRS 99
  • regular atrial cardiac myocyte CL0002129
    CSI 7.11
    rCSI 22.88%
    PRS 98.68
  • adipocyte CL0000136
    CSI 4.97
    rCSI 6.38%
    PRS 98.63
  • endocardial cell CL0002350
    CSI 4.37
    rCSI 20.9%
    PRS 99.1
  • erythroblast CL0000765
    CSI 3.95
    rCSI 10.48%
    PRS 99.34
  • fibroblast CL0000057
    CSI 3.88
    rCSI 11.15%
    PRS 97.15
  • Schwann cell CL0002573
    CSI 3.43
    rCSI 9.74%
    PRS 99.03
  • cardiac endothelial cell CL0010008
    CSI 3.04
    rCSI 12.25%
    PRS 99.72
  • fast muscle cell CL0000190
    CSI 2.86
    rCSI 11.16%
    PRS 97.03
  • skeletal muscle satellite stem cell CL0008011
    CSI 2.01
    rCSI 8.96%
    PRS 99.85
  • regular ventricular cardiac myocyte CL0002131
    CSI 1.98
    rCSI 12.36%
    PRS 98.36
  • cell of skeletal muscle CL0000188
    CSI 1.39
    rCSI 15.07%
    PRS 98.21

Cell ID: Standard Cell Ontology term used for mapping and comparing cells across experiments. Ensures consistency in analyzing cellular functions across tissues.
Fold Change: Represents the ratio of the current Cell Significance Index to the Cell Significance Index Threshold, indicating how much the gene expression has changed compared to a baseline.
Cell Significance Index: Reflects how strongly a gene is expressed in this specific cell.

Cell ID: Standard Cell Ontology term used for mapping and comparing cells across experiments. Ensures consistency in analyzing cellular functions across tissues.
Fold Change: Represents the ratio of the current Cell Significance Index to the Cell Significance Index Threshold, indicating how much the gene expression has changed compared to a baseline.
Cell Significance Index: Reflects how strongly a gene is expressed in this cell type. Calculated using techniques like effect size estimation and bootstrapping for reliability.

Cell ID: Standard Cell Ontology term used for mapping and comparing cells across experiments. Ensures consistency in analyzing cellular functions across tissues.
Fold Change: Represents the ratio of the current Cell Significance Index to the Cell Significance Index Threshold, indicating how much the gene expression has changed compared to a baseline.
Cell Significance Index: Reflects how strongly a gene is expressed in this cell type. Calculated using techniques like effect size estimation and bootstrapping for reliability.
Network Configuration

Explore relationships of the current gene. Select an Interaction Source: 'ONTOLOGY' for shared pathways (GO/Reactome) or 'STRING' for protein-protein interactions. Further refine by selecting context genes and comparing Cell Significance Index (CSI) scores between baseline and target cell types and their specific contexts.

Comma-separated if multiple.
Comma-separated if multiple.
Legend:
  • Query Gene
  • Node Color (Target Cell CSI, relative to current network):
    • Very High
    • High
    • Medium
    • Low
    • Very Low
    • CSI N/A
  • Node Size: Proportional to Target Cell CSI magnitude
  • STRING PPI Edge
  • Shared Pathway Edge (ONTOLOGY)

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Other Information

This section provides additional information about the gene, including a description generated by an AI language model and details about associated proteins.

## Summary [MYO18B](/details-gene/84700) encodes Myosin-XVIIIb, a large, unconventional myosin motor protein located on chromosome 22q12.1. Functionally, it is involved in cytoskeletal organization, particularly through its ability to bind actin filaments ([GO:0051015](https://www.ebi.ac.uk/QuickGO/term/GO:0051015)) and participate in actomyosin structures ([GO:0031032](https://www.ebi.ac.uk/QuickGO/term/GO:0031032)). Its expression profile is most significant in contractile and hematopoietic lineages. **Overall**, it is a defining marker for [cardiac muscle cell](/details-cell/CL0000746) (CSI: 10.16) and [erythrocyte](/details-cell/CL0000232) (CSI: 9.56), suggesting essential roles in both muscle function and red blood cell biology. Clinically, null mutations in [MYO18B](/details-gene/84700) are linked to a congenital syndrome involving Klippel-Feil anomaly and myopathy ([Link](https://doi.org/10.1136/jmedgenet-2014-102964)), and it has been identified as a candidate tumor suppressor gene in human lung cancer ([Link](https://doi.org/10.1073/pnas.192445899)). ## Cellular Roles and Expression Landscape The expression pattern of [MYO18B](/details-gene/84700) highlights its specialized roles in distinct cell populations. **Overall**, the gene shows the highest significance in cells defined by complex cytoskeletal architecture and contractile processes. Its top ranking in [cardiac muscle cell](/details-cell/CL0000746), [regular atrial cardiac myocyte](/details-cell/CL0002129), and other muscle-related cells like [fast muscle cell](/details-cell/CL0000190) and [cell of skeletal muscle](/details-cell/CL0000188) is consistent with its classification as a myosin and its known expression in striated muscles ([Link](https://doi.org/10.1016/s0022-2836(02)01335-9)). Intriguingly, [MYO18B](/details-gene/84700) also demonstrates very high significance in the erythroid lineage, specifically in mature [erythrocyte](/details-cell/CL0000232) and precursor [erythroblast](/details-cell/CL0000765) populations. This suggests a critical function beyond muscle contraction, potentially related to the extensive cytoskeletal remodeling that occurs during red blood cell development and maturation. The gene's notable expression in structural cells such as [adipocyte](/details-cell/CL0000136), [fibroblast](/details-cell/CL0000057), and [Schwann cell](/details-cell/CL0002573) further points to a broader role in maintaining cellular architecture in diverse tissues. ## Pathways and Molecular Function The functional annotations for [MYO18B](/details-gene/84700) align closely with its identity as a cytoskeletal motor protein. Its molecular functions are centered on [ATP binding](/details-go/GO:0005524), [actin filament binding](/details-go/GO:0051015), and [cytoskeletal motor activity](/details-go/GO:0003774). These activities are integral to the biological processes of [actomyosin structure organization](/details-go/GO:0031032) and development, including [cardiac muscle cell development](/details-go/GO:0055013) and [vasculogenesis](/details-go/GO:0001570). At the subcellular level, the protein localizes to the [cytoplasm](/details-go/GO:0005737) and various myosin and actin-containing structures, such as the [myosin filament](/details-go/GO:0032982), [unconventional myosin complex](/details-go/GO:0016461), and the [Z disc](/details-go/GO:0030018) of muscle sarcomeres. Research has also indicated that upon muscle cell differentiation, [MYO18B](/details-gene/84700) can translocate to the [nucleus](/details-go/GO:0005634), suggesting a potential role in nuclear processes within myocytes ([Link](https://doi.org/10.1016/s0022-2836(02)01335-9)). This dual localization may indicate multifaceted roles in both cytoplasmic transport and nuclear architecture. ## Research Directions The dual prominence of [MYO18B](/details-gene/84700) in both muscle and erythroid lineages, combined with its proposed role as a tumor suppressor, opens several avenues for future investigation. Its function appears highly context-dependent, serving a structural role in differentiated muscle, a potentially dynamic role in erythropoiesis, and a protective role against tumorigenesis. Based on the available data, several testable hypotheses can be proposed: 1. The high significance of [MYO18B](/details-gene/84700) in [erythroblast](/details-cell/CL0000765) and [erythrocyte](/details-cell/CL0000232) suggests it is a key component of the machinery driving cytoskeletal reorganization during erythropoiesis, particularly for the process of enucleation in terminal erythroblasts. 2. Loss of [MYO18B](/details-gene/84700) expression or function in epithelial cells, as reported in lung cancer ([Link](https://doi.org/10.1073/pnas.192445899)), may disrupt actomyosin-dependent cell-cell junctions and cortical tension, thereby promoting an epithelial-to-mesenchymal transition and increasing metastatic potential. 3. In cardiac muscle, the nuclear translocation of [MYO18B](/details-gene/84700) during differentiation ([Link](https://doi.org/10.1016/s0022-2836(02)01335-9)) could be involved in regulating gene expression programs necessary for myocyte maturation or stress responses. To test the role of [MYO18B](/details-gene/84700) in erythropoiesis (Hypothesis 1), one could utilize an *in vitro* differentiation system where human CD34+ hematopoietic stem and progenitor cells are cultured to become mature red blood cells. Using CRISPR-Cas9 to knock out [MYO18B](/details-gene/84700) in these progenitors, subsequent analysis via imaging flow cytometry and confocal microscopy could determine if its absence impairs the rate of enucleation, alters cell morphology, or affects the distribution of key cytoskeletal components like F-actin and spectrin. Given that [MYO18B](/details-gene/84700) mutations are linked to a loss-of-function syndrome and it acts as a tumor suppressor, therapeutic strategies would likely focus on restoring its function or compensating for its loss. Direct reactivation of a large structural protein is challenging. However, understanding the specific cytoskeletal pathways it regulates could uncover downstream nodes that are more amenable to small-molecule intervention. Therefore, while its direct therapeutic potential is currently limited, it may serve as a critical prognostic biomarker, particularly in cancers where its loss is associated with poor outcomes.

Genular Protein ID: 1620706956

Symbol: MY18B_HUMAN

Name: Unconventional myosin-XVIIIb

UniProtKB Accession Codes:

Q8IUG5 A0A075B6F5 B2RWP3 F5GXR6 F5GYU7 Q8NDI8 Q8TE65 Q8WWS0 Q96KH2 Q96KR8 Q96KR9

Database IDs:

AGR 1 AlphaFoldDB 1 Antibodypedia 1 Bgee 1 BioGRID 1 BioGRID-ORCS 1 BioMuta 1 CCDS 2 CDD 1 CTD 1 ChEBI 1 ChiTaRS 1 DMDM 1 DNASU 1 DisGeNET 1 EMBL 17 Ensembl 3 ExpressionAtlas 1 GO 14 Gene3D 6 GeneCards 1 GeneTree 1 GeneWiki 1 GenomeRNAi 1 GlyGen 1 HGNC 1 HOGENOM 1 HPA 1 InParanoid 1 IntAct 1 InterPro 4 KEGG 1 MANE-Select 1 MIM 3 MalaCards 1 MassIVE 1 NCBI Taxonomy 1 OMA 1 OpenTargets 1 Orphanet 1 OrthoDB 1 PANTHER 2 PRINTS 1 PRO 1 PROSITE 2 PathwayCommons 1 PaxDb 1 PeptideAtlas 1 Pfam 1 PharmGKB 1 Pharos 1 PhosphoSitePlus 1 PhylomeDB 1 Proteomes 1 ProteomicsDB 4 Pumba 1 RNAct 1 RefSeq 2 SMART 1 SMR 1 STRING 1 SUPFAM 1 SignaLink 1 TreeFam 1 UCSC 2 VEuPathDB 1 eggNOG 1 iPTMnet 1 jPOST 1 neXtProt 1

Citations:

PubMed ID: 12209013

Title: MYO18B, a candidate tumor suppressor gene at chromosome 22q12.1, deleted, mutated, and methylated in human lung cancer.

PubMed ID: 12209013

DOI: 10.1073/pnas.192445899

PubMed ID: 12547197

Title: Human MYO18B, a novel unconventional myosin heavy chain expressed in striated muscles moves into the myonuclei upon differentiation.

PubMed ID: 12547197

DOI: 10.1016/s0022-2836(02)01335-9

PubMed ID: 10591208

Title: The DNA sequence of human chromosome 22.

PubMed ID: 10591208

DOI: 10.1038/990031

PubMed ID: 15489334

Title: The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).

PubMed ID: 15489334

DOI: 10.1101/gr.2596504

PubMed ID: 17974005

Title: The full-ORF clone resource of the German cDNA consortium.

PubMed ID: 17974005

DOI: 10.1186/1471-2164-8-399

PubMed ID: 12741677

Title: Genetic alterations responsible for metastatic phenotypes of lung cancer cells.

PubMed ID: 12741677

DOI: 10.1023/a:1022978932215

PubMed ID: 14654843

Title: Proteomic characterization of the human centrosome by protein correlation profiling.

PubMed ID: 14654843

DOI: 10.1038/nature02166

PubMed ID: 18088087

Title: Phosphoproteome of resting human platelets.

PubMed ID: 18088087

DOI: 10.1021/pr0704130

PubMed ID: 18669648

Title: A quantitative atlas of mitotic phosphorylation.

PubMed ID: 18669648

DOI: 10.1073/pnas.0805139105

PubMed ID: 19690332

Title: Quantitative phosphoproteomic analysis of T cell receptor signaling reveals system-wide modulation of protein-protein interactions.

PubMed ID: 19690332

DOI: 10.1126/scisignal.2000007

PubMed ID: 23186163

Title: Toward a comprehensive characterization of a human cancer cell phosphoproteome.

PubMed ID: 23186163

DOI: 10.1021/pr300630k

PubMed ID: 25748484

Title: A novel syndrome of Klippel-Feil anomaly, myopathy, and characteristic facies is linked to a null mutation in MYO18B.

PubMed ID: 25748484

DOI: 10.1136/jmedgenet-2014-102964

Sequence Information:

  • Length: 2567
  • Mass: 285215
  • Checksum: C36BFD5C6FB4258B
  • Sequence:
    • MAISSRLALW EQKIREEDKS PPPSSPPPLF SVIPGGFIKQ LVRGTEKEAK EARQRKQLAV 
ASPEREIPEI SISQPNSKSS SGTRSGSQQI SQDDQSSSPG SSDILGKESE GSRSPDPEQM 
TSINGEKAQE LGSSATPTKK TVPFKRGVRR GDVLLMVAKL DPDSAKPEKT HPHDAPPCKT 
SPPATDTGKE KKGETSRTPC GSQASTEILA PKAEKTRTGG LGDPGQGTVA LKKGEEGQSI 
VGKGLGTPKT TELKEAEPQG KDRQGTRPQA QGPGEGVRPG KAEKEGAEPT NTVEKGNVSK 
DVGSEGKHVR PQIPGRKWGG FLGRRSKWDG PQNKKDKEGV LLSKAEKTGE PQTQMEKTSQ 
VQGELGDDLR MGEKAGELRS TTGKAGESWD KKEKMGQPQG KSGNAGEARS QTEKGCEAPK 
EVSTMVESPA APGKGGWPGS RGQEAEEPCS RAGDGAGALE TELEGPSQPA LEKDAERPRI 
RKENQDGPAP QEEGKGGQSR DSDQAPEDRW YEAEKVWLAQ KDGFTLATVL KPDEGTADLP 
AGRVRLWIDA DKTITEVDEE HVHRANPPEL DQVEDLASLI SVNESSVLNT LLQRYKAQLL 
HTCTGPDLIV LQPRGPSVPS AGKVPKGRRD GLPAHIGSMA QRAYWALLNQ RRDQSIVALG 
WSGAGKTTCC EQVLEHLVGM AGSVDGRVSV EKIRATFTVL RAFGSVSMAH SRSATRFSMV 
MSLDFNATGR ITAAQLQTML LEKSRVARQP EGESNFLVFS QMLAGLDLDL RTELNLHQMA 
DSSSFGMGVW SKPEDKQKAA AAFAQLQGAM EMLGISESEQ RAVWRVLAAI YHLGAAGACK 
VGRKQFMRFE WANYAAEALG CEYEELNTAT FKHHLRQIIQ QMTFGPSRWG LEDEETSSGL 
KMTGVDCVEG MASGLYQELF AAVVSLINRS FSSHHLSMAS IMVVDSPGFQ NPRHQGKDRA 
ATFEELCHNY AHERLQLLFY QRTFVSTLQR YQEEGVPVQF DLPDPSPGTT VAVVDQNPSQ 
VRLPAGGGAQ DARGLFWVLD EEVHVEGSSD SVVLERLCAA FEKKGAGTEG SSALRTCEQP 
LQCEIFHQLG WDPVRYDLTG WLHRAKPNLS ALDAPQVLHQ SKREELRSLF QARAKLPPVC 
RAVAGLEGTS QQALQRSRMV RRTFASSLAA VRRKAPCSQI KLQMDALTSM IKRSRLHFIH 
CLVPNPVVES RSGQESPPPP QPGRDKPGAG GPLALDIPAL RVQLAGFHIL EALRLHRTGY 
ADHMGLTRFR RQFQVLDAPL LKKLMSTSEG IDERKAVEEL LETLDLEKKA VAVGHSQVFL 
KAGVISRLEK QREKLVSQSI VLFQAACKGF LSRQEFKKLK IRRLAAQCIQ KNVAVFLAVK 
DWPWWQLLGS LQPLLSATIG TEQLRAKEEE LTTLRRKLEK SEKLRNELRQ NTDLLESKIA 
DLTSDLADER FKGDVACQVL ESERAERLQA FREVQELKSK HEQVQKKLGD VNKQLEEAQQ 
KIQLNDLERN PTGGADEWQM RFDCAQMENE FLRKRLQQCE ERLDSELTAR KELEQKLGEL 
QSAYDGAKKM AHQLKRKCHH LTCDLEDTCV LLENQQSRNH ELEKKQKKFD LQLAQALGES 
VFEKGLREKV TQENTSVRWE LGQLQQQLKQ KEQEASQLKQ QVEMLQDHKR ELLGSPSLGE 
NCVAGLKERL WKLESSALEQ QKIQSQQENT IKQLEQLRQR FELEIERMKQ MHQKDREDQE 
EELEDVRQSC QKRLHQLEMQ LEQEYEEKQM VLHEKQDLEG LIGTLCDQIG HRDFDVEKRL 
RRDLRRTHAL LSDVQLLLGT MEDGKTSVSK EELEKVHSQL EQSEAKCEEA LKTQKVLTAD 
LESMHSELEN MTRNKSLVDE QLYRLQFEKA DLLKRIDEDQ DDLNELMQKH KDLIAQSAAD 
IGQIQELQLQ LEEAKKEKHK LQEQLQVAQM RIEYLEQSTV DRAIVSRQEA VICDLENKTE 
FQKVQIKRFE VLVIRLRDSL IKMGEELSQA ATSESQQRES SQYYQRRLEE LKADMEELVQ 
REAEASRRCM ELEKYVEELA AVRQTLQTDL ETSIRRIADL QAALEEVASS DSDTESVQTA 
VDCGSSGRKE MDNVSILSSQ PEGSLQSWLS CTLSLATDTM RTPSRQSATS SRILSPRINE 
EAGDTERTQS ALALSRARST NVHSKTSGDK PVSPHFVRRQ KYCHFGDGEV LAVQRKSTER 
LEPASSPLAS RSTNTSPLSR EKLPSPSAAL SEFVEGLRRK RAQRGQGSTL GLEDWPTLPI 
YQTTGASTLR RGRAGSDEGN LSLRVGAKSP LEIEGAAGGL LRSTSLKCIS SDGVGGTTLL 
PEKSKTQFSS CESLLESRPS MGRKLSSPTT PRDMLLSPTL RPRRRCLESS VDDAGCPDLG 
KEPLVFQNRQ FAHLMEEPLG SDPFSWKLPS LDYERKTKVD FDDFLPAIRK PQTPTSLAGS 
AKGGQDGSQR SSIHFETEEA NRSFLSGIKT ILKKSPEPKE DPAHLSDSSS SSGSIVSFKS 
ADSIKSRPGI PRLAGDGGER TSPERREPGT GRKDDDVASI MKKYLQK