SpermatogenesisOnline 1.0
 

Tag Content
SG ID
SG00000549 
UniProt Accession
Theoretical PI
5.7  
Molecular Weight
70818 Da  
Genbank Nucleotide ID
Genbank Protein ID
Gene Name
SPAG16 
Gene Synonyms/Alias
PF20 
Protein Name
Sperm-associated antigen 16 protein 
Protein Synonyms/Alias
Pf20 protein homolog; 
Organism
Homo sapiens (Human) 
NCBI Taxonomy ID
9606 
Chromosome Location
chr:2;214149113-215275225;1
View in Ensembl genome browser  
Function in Stage
Function in Cell Type
Description
A heterozygous mutation that affects both SPAG16L and SPAG16S does not cause male infertility in man, but is associated with reduced stability of the interacting proteins of the central apparatus in response to a thermal challenge, a phenotype shared by the sperm of mice heterozygous for a mutation that affects SPAG16L. 
The information of related literatures
1. Z. Zhang, M. A. Zariwala, M. M. Mahadevan, P. Caballero-Campo, X. Shen, E. Escudier, B. Duriez, A. M. Bridoux, M. Leigh, G. L. Gerton, M. Kennedy, S. Amselem, M. R. Knowles and J. F. Strauss, 3rd (2007) A heterozygous mutation disrupting the SPAG16 gene results in biochemical instability of central apparatus components of the human sperm axoneme. Biol Reprod 77(5): 864-71. 

Abstract
The SPAG16 gene encodes two major transcripts, one for the 71-kDa SPAG16L, which is the orthologue of the Chlamydomonas rheinhardtii central apparatus protein PF20, and a smaller transcript, which codes for the 35-kDa SPAG16S nuclear protein that represents the C-terminus (exons 11-16) of SPAG16L. We have previously reported that a targeted mutation in exon 11 of the Spag16 gene impairs spermatogenesis and prevents transmission of the mutant allele in chimeric mice. In the present report, we describe a heterozygous mutation in exon 13 of the SPAG16 gene, which causes a frame shift and premature stop codon, affording the opportunity to compare mutations with similar impacts on SPAG16L and SPAG16S for male reproductive function in mice and men. We studied two male heterozygotes for the SPAG16 mutation, both of which were fertile. Freezing-boiling of isolated sperm from both affected males resulted in the loss of the SPAG16L protein, SPAG6, another central apparatus protein that interacts with SPAG16L, and the 28-kDa fragment of SPAG17, which associates with SPAG6. These proteins were also lost after freezing-boiling cycles of sperm extracts from mice that were heterozygous for an inactivating mutation (exons 2 and 3) in Spag16. Our findings suggest that a heterozygous mutation that affects both SPAG16L and SPAG16S does not cause male infertility in man, but is associated with reduced stability of the interacting proteins of the central apparatus in response to a thermal challenge, a phenotype shared by the sperm of mice heterozygous for a mutation that affects SPAG16L. PMID: [17699735] 

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Figures for illustrating the function of this protein/gene
Ref: Z. Zhang, M. A. Zariwala, M. M. Mahadevan, P. Caballero-Campo, X. Shen, E. Escudier, B. Duriez, A. M. Bridoux, M. Leigh, G. L. Gerton, M. Kennedy, S. Amselem, M. R. Knowles and J. F. Strauss, 3rd (2007) A heterozygous mutation disrupting the SPAG16 gene results in biochemical instability of central apparatus components of the human sperm axoneme. Biol Reprod 77(5): 864-71. PMID: [17699735]
Function
Necessary for sperm flagellar function. Plays a role inmotile ciliogenesis. May help to recruit STK36 to the cilium orapical surface of the cell to initiate subsequent steps ofconstruction of the central pair apparatus of motile cilia (Bysimilarity). 
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Subcellular Location
Cytoplasm (By similarity). Cytoplasm,cytoskeleton, flagellum axoneme (By similarity). Cytoplasm,cytoskeleton, cilium axoneme (By similarity). Note=Detected on thesperm flagellum axoneme. Detected in the central apparatus of theaxoneme. Colocalizes with SPAG6 on microtubules (By similarity). 
Tissue Specificity
Isoform 1 is detected in testis. Isoform 4 isdetected in testis and brain, and at lower levels in kidney,heart, pancreas, thyroid, ovary, adrenal gland, spinal cord,trachea and liver. 
Gene Ontology
GO IDGO termEvidence
GO:0035085 C:cilium axoneme ISS:UniProtKB.
GO:0005856 C:cytoskeleton IEA:UniProtKB-KW.
GO:0035086 C:flagellar axoneme IEA:UniProtKB-SubCell.
GO:0042384 P:cilium assembly ISS:UniProtKB.
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Interpro
IPR020472;    G-protein_beta_WD-40_rep.
IPR015943;    WD40/YVTN_repeat-like_dom.
IPR001680;    WD40_repeat.
IPR019775;    WD40_repeat_CS.
IPR017986;    WD40_repeat_dom.
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Pfam
PF00400;    WD40;    6.
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SMART
SM00320;    WD40;    7.
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PROSITE
PS00678;    WD_REPEATS_1;    3.
PS50082;    WD_REPEATS_2;    5.
PS50294;    WD_REPEATS_REGION;    1.
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PRINTS
PR00320;    GPROTEINBRPT.;   
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Created Date
18-Oct-2012 
Record Type
Experiment identified 
Protein sequence Annotation
CHAIN         1    631       Sperm-associated antigen 16 protein.
                             /FTId=PRO_0000051223.
REPEAT      350    389       WD 1.
REPEAT      392    431       WD 2.
REPEAT      434    473       WD 3.
REPEAT      476    515       WD 4.
REPEAT      518    557       WD 5.
REPEAT      560    600       WD 6.
REPEAT      601    630       WD 7.
COILED      152    267       Potential.
VAR_SEQ       1    149       Missing (in isoform 2).
                             /FTId=VSP_013494.
VAR_SEQ       1     61       MAAQRGMPSSAVRVLEEALGMGLTAAGDARDTADAVAAEGA
                             YYLEQVTITEASEDDYEYEE -> MGVGTKARASHWRRLLS
                             LGATPEEPLLDFK (in isoform 3).
                             /FTId=VSP_013493.
VAR_SEQ     150    179       VPDVYTQIMLLENENKNLKKDLKHYKQAAD -> MTILASQ
                             KVKKIWQKQFRWPKNRLQILKFC (in isoform 2).
                             /FTId=VSP_013495.
VAR_SEQ     179    183       DKARE -> EYVIF (in isoform 4).
                             /FTId=VSP_013496.
VAR_SEQ     184    631       Missing (in isoform 4).
                             /FTId=VSP_013497.
VAR_SEQ     278    282       VDHSR -> GKGCM (in isoform 3).
                             /FTId=VSP_013498.
VAR_SEQ     283    631       Missing (in isoform 3).
                             /FTId=VSP_013499.
VAR_SEQ     315    347       DSEFPIDMQPNPNLNVSKESLSPAKFDYKLKNI -> QWTG
                             NSQTWNKTVPLQDTIGRRQENNSAHQHID (in isoform
                             5).
                             /FTId=VSP_013500.
VAR_SEQ     348    631       Missing (in isoform 5).
                             /FTId=VSP_013501.
VAR_SEQ     574    631       GRVLAQASGNGVIHLLDLKSGEIHKLMGHENEAHTVVFSHD
                             GEILFSGGSDGTVRTWS -> ENTTYLYRPGAQIYYFQLS
                             (in isoform 2).
                             /FTId=VSP_013502.
VARIANT     324    324       P -> T (in dbSNP:rs10167688).
                             /FTId=VAR_053418.
VARIANT     361    361       Q -> H (in dbSNP:rs2042791).
                             /FTId=VAR_022366.
VARIANT     425    425       K -> T (in dbSNP:rs12623569).
                             /FTId=VAR_022367.
CONFLICT     49     49       I -> T (in Ref. 4; CAG33640).
CONFLICT    100    100       P -> L (in Ref. 4; CAG33640).
CONFLICT    173    173       H -> Q (in Ref. 4; CAG33640).
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Nucleotide Sequence
Length: 2121 bp   Go to nucleotide: FASTA
Protein Sequence
Length: 631 bp   Go to amino acid: FASTA
The verified Protein-Protein interaction information
UniProt
 Gene Symbol Ref Databases
MEIG1HPRD 
rpoHIntAct 
SPAG6HPRD 
Other Protein-Protein interaction resources
String database  
View Microarray data
Temporarily unavailable 
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