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P34092 (MYOB_DICDI) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 100. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Myosin IB heavy chain
Gene names
Name:myoB
Synonyms:dmiB, myoA
ORF Names:DDB_G0289117
OrganismDictyostelium discoideum (Slime mold) [Reference proteome]
Taxonomic identifier44689 [NCBI]
Taxonomic lineageEukaryotaAmoebozoaMycetozoaDictyosteliidaDictyostelium

Protein attributes

Sequence length1111 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Myosin is a protein that binds to actin and has ATPase activity that is activated by actin. Myosin IB may have a role in chemotaxis and aggregation; it could serve to stabilize and even retract cortical structures, such as pseudopods and lamellopods. Involved in the whole cell motility of aggregation-stages cells. Overexpression results in significant decrease in the rate of cellular translocation and fluid-phase pinocytosis and abnormalities in the normal rearrangement of the actin cytoskeleton. Ref.9 Ref.10 Ref.13

Subunit structure

Myosin I heavy chain is single-headed. Dimer of a heavy and a light chain. Inability to self-assemble into filaments.

Subcellular location

Cell projectionpseudopodium. Cytoplasmcell cortex. Note: Highest concentration just beneath the plasma membrane in the anterior pseudopod at the leading edge of the cell and at sites of cell-cell contact in both stationary and aggregation stage cells. Also found in macropinocytic structures. Ref.3 Ref.4 Ref.8 Ref.9

Developmental stage

Rises dramatically during early development. Ref.9

Domain

TH.1 binds directly to anionic phospholipid membranes; myosins I could therefore move actin relative to membranes and vice versa. TH.2 and SH3 bind tightly to F-actin; this together with the nucleotide-sensitive site in the head, allows single molecules of myosin I to cross-link actin filaments.

Disruption phenotype

Shows defects in pseudopod formation and translocation. Also shows slower speed of locomoting, aggregation-stage cells and significant reduction in initial rate of phagocytosis. MyoB and myoC double mutant exhibits profound defects in growth, endocytosis and rearrangment of F-actin. Expression of the full-length myoB heavy chain in these cells fully rescues the double mutant defects. myoB and myoD double mutant exhibits reduction in the speed of whole cell translocation. myoB, myoC and myoD triple mutant exhibits reduction in the speed of whole cell translocation. Ref.5 Ref.6 Ref.7 Ref.9 Ref.11

Sequence similarities

Contains 1 myosin head-like domain.

Contains 1 SH3 domain.

Ontologies

Keywords
   Biological processChemotaxis
   Cellular componentCell projection
Cytoplasm
   DomainSH3 domain
   LigandActin-binding
ATP-binding
Nucleotide-binding
   Molecular functionMotor protein
Myosin
   PTMPhosphoprotein
   Technical termComplete proteome
Direct protein sequencing
Reference proteome
Gene Ontology (GO)
   Biological_processATP catabolic process

Inferred from direct assay PubMed 18089562. Source: GOC

actin-myosin filament sliding

Inferred from direct assay PubMed 18089562. Source: dictyBase

cellular component movement

Inferred from mutant phenotype Ref.9. Source: dictyBase

chemotaxis

Inferred from electronic annotation. Source: UniProtKB-KW

exocytosis

Inferred from expression pattern PubMed 21190565. Source: dictyBase

metabolic process

Inferred from direct assay PubMed 18089562. Source: GOC

phagocytosis

Inferred from mutant phenotype Ref.9. Source: dictyBase

phagosome reneutralization

Inferred from mutant phenotype PubMed 22008230. Source: dictyBase

regulation of post-lysosomal vacuole size

Inferred from mutant phenotype PubMed 22008230. Source: dictyBase

response to other organism

Traceable author statement PubMed 14695060. Source: dictyBase

   Cellular_componentactomyosin

Inferred from direct assay PubMed 18089562. Source: dictyBase

cell cortex

Inferred from electronic annotation. Source: UniProtKB-SubCell

cell leading edge

Traceable author statement Ref.9. Source: dictyBase

phagocytic cup lip

Inferred from direct assay PubMed 20200225. Source: dictyBase

phagocytic vesicle

Inferred from direct assay PubMed 22008230. Source: dictyBase

phagocytic vesicle membrane

Inferred from direct assay PubMed 21190565. Source: dictyBase

pseudopodium

Inferred from electronic annotation. Source: UniProtKB-SubCell

unconventional myosin complex

Inferred from direct assay PubMed 18089562. Source: dictyBase

   Molecular_functionATP binding

Inferred from direct assay PubMed 18089562. Source: dictyBase

actin filament binding

Inferred from direct assay PubMed 18089562. Source: dictyBase

actin-dependent ATPase activity

Inferred from direct assay PubMed 18089562. Source: dictyBase

microfilament motor activity

Inferred from direct assay PubMed 18089562. Source: dictyBase

myosin I head/neck binding

Inferred from direct assay Ref.13. Source: dictyBase

Complete GO annotation...

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 11111111Myosin IB heavy chain
PRO_0000123366

Regions

Domain1 – 694694Myosin head-like
Domain1053 – 111159SH3
Nucleotide binding102 – 1098ATP Potential
Region547 – 62781Actin-binding
Region695 – 921227Tail homology region 1 (TH.1)
Compositional bias922 – 1052131Ala/Gly/Pro-rich (TH.2)
Compositional bias951 – 101565Asn-rich
Compositional bias955 – 96511Poly-Gln

Amino acid modifications

Modified residue3321Phosphoserine By similarity

Experimental info

Mutagenesis3321S → A: Fail to complement the null phenotype. Ref.11 Ref.13
Mutagenesis3321S → E: Forms a complex in the presence and absence of Ca(2+). Ref.11 Ref.13
Sequence conflict2071A → R in AAA33229. Ref.1
Sequence conflict3651R → K in AAA33229. Ref.1

Sequences

Sequence LengthMass (Da)Tools
P34092 [UniParc].

Last modified December 4, 2007. Version 2.
Checksum: B326A1DDF85B86AC

FASTA1,111124,257
        10         20         30         40         50         60 
MSKKVQAKQG TDDLVMLPKV SEDEICENLK KRYMNDFIYT NIGPVLISVN PFRNLNNSGP 

        70         80         90        100        110        120 
DFIEAYRGKH AQEVPPHVYQ LAESAYRAMK NDQENQCVII SGESGAGKTE AAKLIMGYVS 

       130        140        150        160        170        180 
AISGSTEKVE YVKHVILESN PLLEAFGNAK TLRNNNSSRF GKYFEIQFDK AGDPVGGKIY 

       190        200        210        220        230        240 
NYLLEKSRVV YQNPGERNFH IFYQLLAGAS AQEKRDYVLS SPESYYYLNQ SQCYTVDGIN 

       250        260        270        280        290        300 
DVSDYAEVRQ AMDTIGLTAQ EQSDIIRIVA CVLHIGNIYF IEDDKGNAAI YDPNALELAA 

       310        320        330        340        350        360 
SMLCIDSATL QNAILFRVIN TGGAGGAGNR RSTYNVPQNV EQANGTRDAL ARTIYDRMFS 

       370        380        390        400        410        420 
WLVERVNQSL SYYKSPYQNV IGILDIFGFE IFEKNGFEQF CINFVNEKLQ QFFIELTLKA 

       430        440        450        460        470        480 
EQEEYVREGI KWEPIKYFNN QIVCDLIEGK SPPGIFSLLD DICSTLHAQS TGTDQKFLEK 

       490        500        510        520        530        540 
MAGIYDGHLH WRGMTGAFAI KHYAGEVTYE AEGFSDKNKD TLFFDLIEAI QCSKMPFLAS 

       550        560        570        580        590        600 
LFNEDTGSLQ KKRPTTAGFK IKTSAGELMK ALSQCTPHYI RCIKPNETKK AKDWENSRVK 

       610        620        630        640        650        660 
HQVQYLGLLE NVRVRRAGFA YRNTFDKVLK RYKKLSSKTW GIWGEWKGDA IEGCKTIFQD 

       670        680        690        700        710        720 
MNLEAGQWQL GKTKVFIRHP ETVFLLEEAL DKKDFDCTAK IQKAFRNWKA KKHSLEQRAQ 

       730        740        750        760        770        780 
IAHMFKDKKE RQRNSIDRKF TSDYIDFENQ FGLQEAMQNA HKKERVVFAD TVIKIDRRAK 

       790        800        810        820        830        840 
QKNYEMVLTD QALYFVEKSI KKKVLVHTLI RRVGLREIKG VSISTLSDNV IVFHLPEHDQ 

       850        860        870        880        890        900 
VIENDKKTEI IIVLVEYFKA IGGGSLNVQF SDRINYTLKK GEQKEISFQK SEQCPTLVVK 

       910        920        930        940        950        960 
KGGKGLIGTI ASGLPSSTDS TPKNYNPNSM SQASSRPAPQ QSAGRGRGMP QGAGQPQPQQ 

       970        980        990       1000       1010       1020 
PQQQQRPMPQ PQQGGGARPM PQPQQGGGAR PMGAPQQGGA PQQGAGRQLP QPTQQGGAPG 

      1030       1040       1050       1060       1070       1080 
GRGAPMGRGA PGGGPAGAGG RPLPTVAKPA PQPSRPTAKA LYDYDASSTD ELSFKEGDII 

      1090       1100       1110 
FIVQKDNGGW TQGELKSGQK GWAPTNYLQY N 

« Hide

References

« Hide 'large scale' references
[1]"Dictyostelium discoideum contains a gene encoding a myosin I heavy chain."
Jung G., Saxe C.L. III, Kimmel A.R., Hammer J.A. III
Proc. Natl. Acad. Sci. U.S.A. 86:6186-6190(1989) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
Strain: AX3.
[2]"The genome of the social amoeba Dictyostelium discoideum."
Eichinger L., Pachebat J.A., Gloeckner G., Rajandream M.A., Sucgang R., Berriman M., Song J., Olsen R., Szafranski K., Xu Q., Tunggal B., Kummerfeld S., Madera M., Konfortov B.A., Rivero F., Bankier A.T., Lehmann R., Hamlin N. expand/collapse author list , Davies R., Gaudet P., Fey P., Pilcher K., Chen G., Saunders D., Sodergren E.J., Davis P., Kerhornou A., Nie X., Hall N., Anjard C., Hemphill L., Bason N., Farbrother P., Desany B., Just E., Morio T., Rost R., Churcher C.M., Cooper J., Haydock S., van Driessche N., Cronin A., Goodhead I., Muzny D.M., Mourier T., Pain A., Lu M., Harper D., Lindsay R., Hauser H., James K.D., Quiles M., Madan Babu M., Saito T., Buchrieser C., Wardroper A., Felder M., Thangavelu M., Johnson D., Knights A., Loulseged H., Mungall K.L., Oliver K., Price C., Quail M.A., Urushihara H., Hernandez J., Rabbinowitsch E., Steffen D., Sanders M., Ma J., Kohara Y., Sharp S., Simmonds M.N., Spiegler S., Tivey A., Sugano S., White B., Walker D., Woodward J.R., Winckler T., Tanaka Y., Shaulsky G., Schleicher M., Weinstock G.M., Rosenthal A., Cox E.C., Chisholm R.L., Gibbs R.A., Loomis W.F., Platzer M., Kay R.R., Williams J.G., Dear P.H., Noegel A.A., Barrell B.G., Kuspa A.
Nature 435:43-57(2005) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: AX4.
[3]"Sequence, expression pattern, intracellular localization, and targeted disruption of the Dictyostelium myosin ID heavy chain isoform."
Jung G., Fukui Y., Martin B., Hammer J.A. III
J. Biol. Chem. 268:14981-14990(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: PROTEIN SEQUENCE OF 481-490; 656-666 AND 783-798, SUBCELLULAR LOCATION.
Strain: AX3.
[4]"Myosin I is located at the leading edges of locomoting Dictyostelium amoebae."
Fukui Y., Lynch T.J., Brzeska H., Korn E.D.
Nature 341:328-331(1989) [PubMed] [Europe PMC] [Abstract]
Cited for: SUBCELLULAR LOCATION.
[5]"Generation and characterization of Dictyostelium cells deficient in a myosin I heavy chain isoform."
Jung G., Hammer J.A. III
J. Cell Biol. 110:1955-1964(1990) [PubMed] [Europe PMC] [Abstract]
Cited for: DISRUPTION PHENOTYPE.
[6]"Myosin IB null mutants of Dictyostelium exhibit abnormalities in motility."
Wessels D., Murray J., Jung G., Hammer J.A. III, Soll D.R.
Cell Motil. Cytoskeleton 20:301-315(1991) [PubMed] [Europe PMC] [Abstract]
Cited for: DISRUPTION PHENOTYPE.
[7]"Dictyostelium myosin I double mutants exhibit conditional defects in pinocytosis."
Novak K.D., Peterson M.D., Reedy M.C., Titus M.A.
J. Cell Biol. 131:1205-1221(1995) [PubMed] [Europe PMC] [Abstract]
Cited for: DISRUPTION PHENOTYPE.
[8]"Localization of Dictyostelium myoB and myoD to filopodia and cell-cell contact sites using isoform-specific antibodies."
Morita Y.S., Jung G., Hammer J.A. III, Fukui Y.
Eur. J. Cell Biol. 71:371-379(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: SUBCELLULAR LOCATION.
[9]"Dictyostelium mutants lacking multiple classic myosin I isoforms reveal combinations of shared and distinct functions."
Jung G., Wu X., Hammer J.A. III
J. Cell Biol. 133:305-323(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: SUBCELLULAR LOCATION, DISRUPTION PHENOTYPE, DEVELOPMENTAL STAGE, FUNCTION.
[10]"Myosin I overexpression impairs cell migration."
Novak K.D., Titus M.A.
J. Cell Biol. 136:633-647(1997) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION.
[11]"The myosin I SH3 domain and TEDS rule phosphorylation site are required for in vivo function."
Novak K.D., Titus M.A.
Mol. Biol. Cell 9:75-88(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: DISRUPTION PHENOTYPE, MUTAGENESIS OF SER-332.
[12]"Thirteen is enough: the myosins of Dictyostelium discoideum and their light chains."
Kollmar M.
BMC Genomics 7:183-183(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: NOMENCLATURE.
[13]"Identification and characterization of an 8-kDa light chain associated with Dictyostelium discoideum MyoB, a class I myosin."
Crawley S.W., de la Roche M.A., Lee S.F., Li Z., Chitayat S., Smith S.P., Cote G.P.
J. Biol. Chem. 281:6307-6315(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, MUTAGENESIS OF SER-332.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
M26037 Genomic DNA. Translation: AAA33229.1.
AAFI02000130 Genomic DNA. Translation: EAL62866.1.
PIRA33284.

3D structure databases

ProteinModelPortalP34092.
SMRP34092. Positions 1059-1109.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

STRING44689.DDB_0191351.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblProtistsDDB0191351; DDB0191351; DDB_G0289117.
KEGGddi:DDB_G0289117.

Organism-specific databases

dictyBaseDDB_G0289117. myoB.

Phylogenomic databases

eggNOGCOG5022.
KOK10356.
OMALFRVINT.
PhylomeDBP34092.
ProtClustDBCLSZ2429812.

Family and domain databases

Gene3D3.40.50.300. 2 hits.
InterProIPR001609. Myosin_head_motor_dom.
IPR010926. Myosin_tail_2.
IPR027417. P-loop_NTPase.
IPR001452. SH3_domain.
[Graphical view]
PfamPF00063. Myosin_head. 1 hit.
PF06017. Myosin_TH1. 1 hit.
PF00018. SH3_1. 1 hit.
[Graphical view]
PRINTSPR00193. MYOSINHEAVY.
PR00452. SH3DOMAIN.
SMARTSM00242. MYSc. 1 hit.
SM00326. SH3. 1 hit.
[Graphical view]
SUPFAMSSF50044. SSF50044. 1 hit.
SSF52540. SSF52540. 1 hit.
PROSITEPS50002. SH3. 1 hit.
[Graphical view]
ProtoNetSearch...

Entry information

Entry nameMYOB_DICDI
AccessionPrimary (citable) accession number: P34092
Secondary accession number(s): Q54HY1
Entry history
Integrated into UniProtKB/Swiss-Prot: February 1, 1994
Last sequence update: December 4, 2007
Last modified: April 16, 2014
This is version 100 of the entry and version 2 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)

Relevant documents

SIMILARITY comments

Index of protein domains and families

Dictyostelium discoideum

Dictyostelium discoideum: entries, gene names and cross-references to dictyBase