SpermatogenesisOnline 1.0
 

Tag Content
SG ID
SG00000571 
UniProt Accession
Theoretical PI
6.59  
Molecular Weight
109865 Da  
Genbank Nucleotide ID
Genbank Protein ID
Gene Name
KIT 
Gene Synonyms/Alias
SCFR 
Protein Name
Mast/stem cell growth factor receptor Kit 
Protein Synonyms/Alias
SCFREC=2.7.10.1 Piebald trait protein;PBT Proto-oncogene c-Kit; Tyrosine-protein kinase Kit; p145 c-kit; v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog; CD_antigen=CD117;Flags: Precursor 
Organism
Homo sapiens (Human) 
NCBI Taxonomy ID
9606 
Chromosome Location
chr:4;55524085-55606881;1
View in Ensembl genome browser  
Function in Stage
Function in Cell Type
Description
The results of the present study may expand current knowledge about the c-kit/SCF system in human spermatogenesis.  
The information of related literatures
1. S. K. Unni, D. N. Modi, S. G. Pathak, J. V. Dhabalia and D. Bhartiya (2009) Stage-specific localization and expression of c-kit in the adult human testis. J Histochem Cytochem 57(9): 861-9. 

Abstract
The c-kit receptor (KIT) and its ligand, stem cell factor (SCF), represent one of the key regulators of testicular formation, development, and function and have been extensively studied in various animal models. The present study was undertaken to characterize the pattern of localization and expression of c-kit in normal adult human testis. Immunohistochemical analysis showed that KIT is expressed in the cytoplasm of spermatogonia, acrosomal granules of spermatids, and Leydig cells. Interestingly, a rather heterogenous pattern of expression of the protein along the basement membrane was observed. Intense protein localization in spermatogonia was detected in stages I-III, whereas low expression was observed in stages IV-VI of the seminiferous epithelium, indicating that the expression of the molecule was stage specific. In situ hybridization studies revealed that the transcripts of the gene were also localized in a similar non-uniform pattern. To the best of our knowledge, such a stage-specific expression of KIT has not been reported previously in the human testis. The results of the present study may expand current knowledge about the c-kit/SCF system in human spermatogenesis. PMID: [19435714] 

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Figures for illustrating the function of this protein/gene
Ref: S. K. Unni, D. N. Modi, S. G. Pathak, J. V. Dhabalia and D. Bhartiya (2009) Stage-specific localization and expression of c-kit in the adult human testis. J Histochem Cytochem 57(9): 861-9. PMID: [19435714]
Ref: S. K. Unni, D. N. Modi, S. G. Pathak, J. V. Dhabalia and D. Bhartiya (2009) Stage-specific localization and expression of c-kit in the adult human testis. J Histochem Cytochem 57(9): 861-9. PMID: [19435714]
Function
Tyrosine-protein kinase that acts as cell-surfacereceptor for the cytokine KITLG/SCF and plays an essential role inthe regulation of cell survival and proliferation, hematopoiesis,stem cell maintenance, gametogenesis, mast cell development,migration and function, and in melanogenesis. In response toKITLG/SCF binding, KIT can activate several signaling pathways.Phosphorylates PIK3R1, PLCG1, SH2B2/APS and CBL. Activates theAKT1 signaling pathway by phosphorylation of PIK3R1, theregulatory subunit of phosphatidylinositol 3-kinase. Activated KITalso transmits signals via GRB2 and activation of RAS, RAF1 andthe MAP kinases MAPK1/ERK2 and/or MAPK3/ERK1. Promotes activationof STAT family members STAT1, STAT3, STAT5A and STAT5B. Activationof PLCG1 leads to the production of the cellular signalingmolecules diacylglycerol and inositol 1,4,5-trisphosphate. KITsignaling is modulated by protein phosphatases, and by rapidinternalization and degradation of the receptor. Activated KITpromotes phosphorylation of the protein phosphatases PTPN6/SHP-1and PTPRU, and of the transcription factors STAT1, STAT3, STAT5Aand STAT5B. Promotes phosphorylation of PIK3R1, CBL, CRK (isoformCrk-II), LYN, MAPK1/ERK2 and/or MAPK3/ERK1, PLCG1, SRC and SHC1. 
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Subcellular Location
Isoform 3: Cytoplasm. Note=Detected in thecytoplasm of spermatozoa, especially in the equatorial andsubacrosomal region of the sperm head. 
Tissue Specificity
Isoform 1 and isoform 2 are detected inspermatogonia and Leydig cells. Isoform 3 is detected in roundspermatids, elongating spermatids and spermatozoa (at proteinlevel). Widely expressed. Detected in the hematopoietic system,the gastrointestinal system, in melanocytes and in germ cells. 
Gene Ontology
GO IDGO termEvidence
GO:0005737 C:cytoplasm IDA:HPA.
GO:0009897 C:external side of plasma membrane IEA:Compara.
GO:0005615 C:extracellular space IDA:BHF-UCL.
GO:0016021 C:integral to membrane IEA:UniProtKB-KW.
GO:0005634 C:nucleus IDA:HPA.
GO:0005886 C:plasma membrane TAS:Reactome.
GO:0005524 F:ATP binding IEA:UniProtKB-KW.
GO:0046872 F:metal ion binding IEA:UniProtKB-KW.
GO:0004716 F:receptor signaling protein tyrosine kinase activity TAS:ProtInc.
GO:0005020 F:stem cell factor receptor activity IEA:Compara.
GO:0004714 F:transmembrane receptor protein tyrosine kinase activity IDA:UniProtKB.
GO:0031532 P:actin cytoskeleton reorganization IDA:UniProtKB.
GO:0000187 P:activation of MAPK activity IDA:UniProtKB.
GO:0097067 P:cellular response to thyroid hormone stimulus IEA:Compara.
GO:0002371 P:dendritic cell cytokine production ISS:UniProtKB.
GO:0050910 P:detection of mechanical stimulus involved in sensory perception of sound ISS:UniProtKB.
GO:0048565 P:digestive tract development ISS:UniProtKB.
GO:0035162 P:embryonic hemopoiesis ISS:UniProtKB.
GO:0030218 P:erythrocyte differentiation ISS:UniProtKB.
GO:0038162 P:erythropoietin-mediated signaling pathway ISS:UniProtKB.
GO:0038093 P:Fc receptor signaling pathway IDA:UniProtKB.
GO:0035234 P:germ cell programmed cell death IEA:Compara.
GO:0006687 P:glycosphingolipid metabolic process IEA:Compara.
GO:0002327 P:immature B cell differentiation ISS:UniProtKB.
GO:0006954 P:inflammatory response ISS:UniProtKB.
GO:0007243 P:intracellular protein kinase cascade IEA:Compara.
GO:0038109 P:Kit signaling pathway IDA:UniProtKB.
GO:0030032 P:lamellipodium assembly ISS:UniProtKB.
GO:0002320 P:lymphoid progenitor cell differentiation IEA:Compara.
GO:0008584 P:male gonad development IEP:UniProtKB.
GO:0002551 P:mast cell chemotaxis IDA:UniProtKB.
GO:0032762 P:mast cell cytokine production IDA:UniProtKB.
GO:0043303 P:mast cell degranulation IMP:UniProtKB.
GO:0060374 P:mast cell differentiation ISS:UniProtKB.
GO:0070662 P:mast cell proliferation TAS:UniProtKB.
GO:0035855 P:megakaryocyte development ISS:UniProtKB.
GO:0097326 P:melanocyte adhesion ISS:UniProtKB.
GO:0030318 P:melanocyte differentiation ISS:UniProtKB.
GO:0097324 P:melanocyte migration ISS:UniProtKB.
GO:0002318 P:myeloid progenitor cell differentiation IEA:Compara.
GO:0043069 P:negative regulation of programmed cell death IEA:Compara.
GO:0001541 P:ovarian follicle development ISS:UniProtKB.
GO:0018108 P:peptidyl-tyrosine phosphorylation IDA:UniProtKB.
GO:0008284 P:positive regulation of cell proliferation IEA:Compara.
GO:0010628 P:positive regulation of gene expression IEA:Compara.
GO:0043410 P:positive regulation of MAPK cascade IMP:UniProtKB.
GO:0043552 P:positive regulation of phosphatidylinositol 3-kinase activity TAS:UniProtKB.
GO:0014068 P:positive regulation of phosphatidylinositol 3-kinase cascade TAS:UniProtKB.
GO:0010863 P:positive regulation of phospholipase C activity TAS:UniProtKB.
GO:0051091 P:positive regulation of sequence-specific DNA binding transcription factor activity IMP:UniProtKB.
GO:0042511 P:positive regulation of tyrosine phosphorylation of Stat1 protein IMP:UniProtKB.
GO:0042517 P:positive regulation of tyrosine phosphorylation of Stat3 protein IMP:UniProtKB.
GO:0042523 P:positive regulation of tyrosine phosphorylation of Stat5 protein IMP:UniProtKB.
GO:0046777 P:protein autophosphorylation IDA:UniProtKB.
GO:0042127 P:regulation of cell proliferation TAS:UniProtKB.
GO:0008360 P:regulation of cell shape ISS:UniProtKB.
GO:0048070 P:regulation of developmental pigmentation IEA:Compara.
GO:0009314 P:response to radiation IEA:Compara.
GO:0007286 P:spermatid development IEA:Compara.
GO:0007283 P:spermatogenesis ISS:UniProtKB.
GO:0019827 P:stem cell maintenance TAS:UniProtKB.
GO:0030217 P:T cell differentiation ISS:UniProtKB.
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Interpro
IPR007110;    Ig-like.
IPR013783;    Ig-like_fold.
IPR003599;    Ig_sub.
IPR003598;    Ig_sub2.
IPR013151;    Immunoglobulin.
IPR011009;    Kinase-like_dom.
IPR000719;    Prot_kinase_cat_dom.
IPR017441;    Protein_kinase_ATP_BS.
IPR001245;    Ser-Thr/Tyr_kinase_cat_dom.
IPR008266;    Tyr_kinase_AS.
IPR020635;    Tyr_kinase_cat_dom.
IPR016243;    Tyr_kinase_CSF1/PDGF_rcpt.
IPR001824;    Tyr_kinase_rcpt_3_CS.
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Pfam
PF00047;    ig;    1.
PF07714;    Pkinase_Tyr;    1.
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SMART
SM00409;    IG;    1.
SM00408;    IGc2;    1.
SM00219;    TyrKc;    1.
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PROSITE
PS50835;    IG_LIKE;    1.
PS00107;    PROTEIN_KINASE_ATP;    1.
PS50011;    PROTEIN_KINASE_DOM;    1.
PS00109;    PROTEIN_KINASE_TYR;    1.
PS00240;    RECEPTOR_TYR_KIN_III;    1.
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PRINTS
Created Date
18-Oct-2012 
Record Type
Experiment identified 
Protein sequence Annotation
SIGNAL        1     25       Potential.
CHAIN        26    976       Mast/stem cell growth factor receptor
                             Kit.
                             /FTId=PRO_0000016754.
TOPO_DOM     26    524       Extracellular (Potential).
TRANSMEM    525    545       Helical; (Potential).
TOPO_DOM    546    976       Cytoplasmic (Potential).
DOMAIN       27    112       Ig-like C2-type 1.
DOMAIN      121    205       Ig-like C2-type 2.
DOMAIN      212    308       Ig-like C2-type 3.
DOMAIN      317    410       Ig-like C2-type 4.
DOMAIN      413    507       Ig-like C2-type 5.
DOMAIN      589    937       Protein kinase.
NP_BIND     596    603       ATP.
NP_BIND     671    677       ATP.
REGION      568    570       Important for interaction with
                             phosphotyrosine-binding proteins.
ACT_SITE    792    792       Proton acceptor (By similarity).
METAL       568    568       Magnesium.
METAL       797    797       Magnesium.
METAL       810    810       Magnesium.
BINDING     623    623       ATP.
BINDING     796    796       ATP.
SITE        936    936       Important for interaction with
                             phosphotyrosine-binding proteins.
MOD_RES     547    547       Phosphotyrosine; by autocatalysis
                             (Probable).
MOD_RES     553    553       Phosphotyrosine; by autocatalysis
                             (Probable).
MOD_RES     568    568       Phosphotyrosine; by autocatalysis.
MOD_RES     570    570       Phosphotyrosine; by autocatalysis.
MOD_RES     703    703       Phosphotyrosine; by autocatalysis.
MOD_RES     721    721       Phosphotyrosine; by autocatalysis.
MOD_RES     730    730       Phosphotyrosine; by autocatalysis
                             (Probable).
MOD_RES     741    741       Phosphoserine; by PKC/PRKCA.
MOD_RES     746    746       Phosphoserine; by PKC/PRKCA.
MOD_RES     821    821       Phosphoserine.
MOD_RES     823    823       Phosphotyrosine; by autocatalysis.
MOD_RES     891    891       Phosphoserine.
MOD_RES     900    900       Phosphotyrosine; by autocatalysis.
MOD_RES     936    936       Phosphotyrosine; by autocatalysis.
MOD_RES     959    959       Phosphoserine.
CARBOHYD    130    130       N-linked (GlcNAc...).
CARBOHYD    145    145       N-linked (GlcNAc...) (Potential).
CARBOHYD    283    283       N-linked (GlcNAc...).
CARBOHYD    293    293       N-linked (GlcNAc...).
CARBOHYD    300    300       N-linked (GlcNAc...).
CARBOHYD    320    320       N-linked (GlcNAc...).
CARBOHYD    352    352       N-linked (GlcNAc...).
CARBOHYD    367    367       N-linked (GlcNAc...).
CARBOHYD    463    463       N-linked (GlcNAc...) (Potential).
CARBOHYD    486    486       N-linked (GlcNAc...) (Potential).
DISULFID     58     97
DISULFID    136    186
DISULFID    151    183
DISULFID    233    290
DISULFID    428    491
VAR_SEQ     412    413       KP -> SL (in isoform 3).
                             /FTId=VSP_041866.
VAR_SEQ     414    976       Missing (in isoform 3).
                             /FTId=VSP_041867.
VAR_SEQ     510    513       Missing (in isoform 2).
                             /FTId=VSP_038385.
VARIANT     532    532       V -> I (in dbSNP:rs55792975).
                             /FTId=VAR_042021.
VARIANT     541    541       M -> L (in dbSNP:rs3822214).
                             /FTId=VAR_042022.
VARIANT     541    541       M -> V (in dbSNP:rs3822214).
                             /FTId=VAR_061289.
VARIANT     550    558       Missing (in GIST; somatic mutation).
                             /FTId=VAR_033124.
VARIANT     550    550       K -> I (in GIST; somatic mutation;
                             dbSNP:rs28933968).
                             /FTId=VAR_033123.
VARIANT     551    555       Missing (in GIST; somatic mutation).
                             /FTId=VAR_033125.
VARIANT     559    560       Missing (in GIST; somatic mutation).
                             /FTId=VAR_033128.
VARIANT     559    559       V -> A (in GIST).
                             /FTId=VAR_033126.
VARIANT     559    559       V -> D (in GIST; somatic mutation).
                             /FTId=VAR_033127.
VARIANT     559    559       Missing (in GIST).
                             /FTId=VAR_007965.
VARIANT     583    583       E -> K (in PBT).
                             /FTId=VAR_004104.
VARIANT     584    584       F -> C (in PBT; dbSNP:rs28933371).
                             /FTId=VAR_033129.
VARIANT     584    584       F -> L (in PBT).
                             /FTId=VAR_004105.
VARIANT     601    601       G -> R (in PBT).
                             /FTId=VAR_033130.
VARIANT     656    656       L -> P (in PBT).
                             /FTId=VAR_033131.
VARIANT     664    664       G -> R (in PBT).
                             /FTId=VAR_004106.
VARIANT     691    691       C -> S (in dbSNP:rs35200131).
                             /FTId=VAR_042023.
VARIANT     715    715       S -> N (in dbSNP:rs56094246).
                             /FTId=VAR_042024.
VARIANT     737    737       D -> N (in a colorectal adenocarcinoma
                             sample; somatic mutation).
                             /FTId=VAR_042025.
VARIANT     791    791       R -> G (in PBT).
                             /FTId=VAR_004107.
VARIANT     796    796       R -> G (in PBT; with sensorineural
                             deafness).
                             /FTId=VAR_033132.
VARIANT     804    804       R -> W (in a colorectal adenocarcinoma
                             sample; somatic mutation).
                             /FTId=VAR_042026.
VARIANT     812    812       G -> V (in PBT).
                             /FTId=VAR_004108.
VARIANT     816    816       D -> F (in mastocytosis; requires 2
                             nucleotide substitutions; somatic
                             mutation; constitutively activated and is
                             much more rapidly autophosphorylated than
                             wild type).
                             /FTId=VAR_033133.
VARIANT     816    816       D -> H (in a testicular tumor; seminoma;
                             somatic mutation; constitutively
                             activated; dbSNP:rs28933969).
                             /FTId=VAR_033134.
VARIANT     816    816       D -> V (in mast cell leukemia and
                             mastocytosis; somatic mutation;
                             constitutively activated; loss of
                             interaction with MPDZ).
                             /FTId=VAR_004109.
VARIANT     816    816       D -> Y (in acute myeloid leukemia,
                             mastocytosis and a germ cell tumor of the
                             testis; somatic mutation; constitutively
                             activated).
                             /FTId=VAR_023828.
VARIANT     820    820       D -> G (in mast cell disease; systemic).
                             /FTId=VAR_033135.
VARIANT     822    822       N -> K (in a germ cell tumor of the
                             testis; somatic mutation).
                             /FTId=VAR_023829.
VARIANT     829    829       A -> P (in a germ cell tumor of the
                             testis; somatic mutation).
                             /FTId=VAR_023830.
VARIANT     839    839       E -> K (in mastocytosis; somatic
                             mutation; dominant negative mutation;
                             loss of autophosphorylation).
                             /FTId=VAR_033136.
VARIANT     847    847       T -> P (in PBT).
                             /FTId=VAR_033137.
VARIANT     893    896       Missing (in PBT; severe).
                             /FTId=VAR_004110.
MUTAGEN     381    381       R->A: Reduces autophosphorylation in
                             response to KITLG/SCF.
MUTAGEN     386    386       E->A: Reduces autophosphorylation in
                             response to KITLG/SCF.
MUTAGEN     571    571       I->A: Reduction in SH2B2/APS binding.
                             Abolishes SH2B2/APS binding; when
                             associated with A-939.
MUTAGEN     623    623       K->M: Stronger interaction with MPDZ.
MUTAGEN     741    741       S->A: Abolishes down-regulation of kinase
                             activity by PKC/PRKCA-mediated
                             phosphorylation; when associated with A-
                             746.
MUTAGEN     746    746       S->A: Abolishes down-regulation of kinase
                             activity by PKC/PRKCA-mediated
                             phosphorylation; when associated with A-
                             741.
MUTAGEN     823    823       Y->F: No decrease in activity. Leads to
                             autophosphorylation at Tyr-900.
MUTAGEN     939    939       L->A: Reduction in SH2B2/APS binding.
                             Abolishes SH2B2/APS binding; when
                             associated with A-571.
CONFLICT    764    764       L -> I (in Ref. 9; AAH71593).
CONFLICT    838    838       P -> H (in Ref. 9; AAH71593).
STRAND       38     41
STRAND       44     47
STRAND       54     59
STRAND       63     72
STRAND       75     77
STRAND       79     86
HELIX        89     91
STRAND       93     99
STRAND      104    110
STRAND      125    130
STRAND      132    134
STRAND      146    149
STRAND      151    153
STRAND      161    165
TURN        166    168
STRAND      169    174
HELIX       177    179
STRAND      183    188
STRAND      193    200
STRAND      203    205
STRAND      213    215
STRAND      219    224
STRAND      229    239
STRAND      243    248
STRAND      258    263
STRAND      265    267
STRAND      269    279
TURN        282    284
STRAND      286    293
STRAND      298    310
STRAND      312    319
STRAND      321    325
STRAND      331    341
STRAND      345    352
STRAND      356    359
STRAND      362    364
STRAND      367    369
STRAND      372    379
HELIX       384    386
STRAND      388    395
STRAND      400    409
STRAND      411    419
STRAND      422    424
STRAND      426    434
STRAND      437    439
STRAND      468    470
STRAND      472    478
STRAND      492    494
STRAND      499    501
STRAND      558    564
STRAND      567    570
TURN        573    575
HELIX       580    582
HELIX       586    588
STRAND      589    597
STRAND      599    613
STRAND      617    625
HELIX       631    647
STRAND      656    660
STRAND      662    665
STRAND      667    671
HELIX       678    684
TURN        685    688
HELIX       766    785
STRAND      788    790
HELIX       795    797
STRAND      798    801
TURN        802    804
STRAND      805    808
HELIX       812    814
HELIX       817    819
STRAND      823    825
STRAND      827    831
HELIX       833    835
HELIX       838    843
HELIX       848    863
TURN        864    866
HELIX       877    885
HELIX       897    906
HELIX       911    913
HELIX       917    930
TURN        931    933
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Nucleotide Sequence
Length: 5084 bp   Go to nucleotide: FASTA
Protein Sequence
Length: 976 bp   Go to amino acid: FASTA
The verified Protein-Protein interaction information
UniProt
 Gene Symbol Ref Databases
PLCG1HPRD 
CBLBBioGRID 
GRB2BioGRID 
_HPRD 
_HPRD 
_HPRD 
_BioGRID 
PRKCAHPRD 
_BioGRID 
BCRBioGRID 
CD63BioGRID 
CBLBBioGRID 
CD63BioGRID 
CD81HPRD 
CD9BioGRID 
CRKLHPRD 
CRKHPRD 
CSF2RAHPRD 
DOK1HPRD 
FYNHPRD 
GRAP2HPRD 
GRAPHPRD 
GRB10HPRD 
GRB2BioGRID 
GRB7HPRD 
HCKHPRD 
CSF2RBHPRD 
PLCG1BioGRID 
PIK3CGHPRD 
_HPRD 
CBLBHPRD 
ABL1HPRD 
GRB2HPRD 
_BioGRID 
_HPRD 
BTKHPRD 
CD63BioGRID 
CBLBHPRD 
CBLHPRD 
CD63BioGRID 
CD81BioGRID 
CD9HPRD 
CISHHPRD 
CLTCHPRD 
CRKLBioGRID 
CRKMINT 
UbcBioGRID 
EPORHPRD 
GRB10BioGRID 
GRB2HPRD 
GRB7MINT 
JAK2HPRD 
KITHPRD 
KITHPRD 
PRKCBHPRD 
LCKHPRD 
LYNBioGRID 
MATKBioGRID 
MPDZBioGRID 
PIK3R1BioGRID 
PIK3R2BioGRID 
PIK3CGHPRD 
PLCE1HPRD 
PLCG1BioGRID 
PTPN11BioGRID 
PTPN6BioGRID 
PTPROBioGRID 
PTPRUHPRD 
SOCS1BioGRID 
PLCG1BioGRID 
SOCS5HPRD 
PTPN6BioGRID 
_HPRD 
_HPRD 
BTKHPRD 
KITHPRD 
LYNBioGRID 
DKFZp434N1212BioGRID 
PTPROBioGRID 
PTPROBioGRID 
DKFZp434N101BioGRID 
_BioGRID 
RFC1BioGRID 
KITLGBioGRID 
INPP5DHPRD 
SOCS1BioGRID 
SOCS5HPRD 
SOCS6HPRD 
STAT5AHPRD 
STAT5BHPRD 
STAT1HPRD 
TECBioGRID 
UBCBioGRID 
YES1BioGRID 
PRKCAHPRD 
LCKBioGRID 
LYNHPRD 
MATKHPRD 
MPDZHPRD 
PIK3R1HPRD 
PIK3R2HPRD 
PLCG1HPRD 
PTPN11HPRD 
Ptpn11IntAct 
PTPN6HPRD 
PTPRJIntAct 
PTPROHPRD 
SOCS1HPRD 
PLCG1HPRD 
PTPN6BioGRID 
GRB7HPRD 
_HPRD 
SH3KBP1BioGRID 
SH3KBP1BioGRID 
SH3KBP1BioGRID 
GRAP2HPRD 
KITHPRD 
CSF2RBHPRD 
LYNHPRD 
PRKCAHPRD 
DKFZp434N1212BioGRID 
DKFZp434N101HPRD 
_HPRD 
RASA1HPRD 
KITLGHPRD 
SH2B2HPRD 
SH2B3HPRD 
SH3KBP1BioGRID 
SOCS1HPRD 
SPRED1HPRD 
SPRED2HPRD 
SRCHPRD 
STAP1HPRD 
STAT1BioGRID 
TECHPRD 
YES1HPRD 
Other Protein-Protein interaction resources
String database  
View Microarray data
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