Phenotypic Mutation 'm2sd2' (pdf version)
Mutation Type nonsense
Coordinate64,954,394 bp (GRCm38)
Base Change A ⇒ T (forward strand)
Gene Tlr6
Gene Name toll-like receptor 6
Chromosomal Location 64,952,031-64,960,097 bp (-)
MGI Phenotype FUNCTION: [Summary is not available for the mouse gene. This summary is for the human ortholog.] The protein encoded by this gene is a member of the Toll-like receptor (TLR) family which plays a fundamental role in pathogen recognition and activation of innate immunity. TLRs are highly conserved from Drosophila to humans and share structural and functional similarities. They recognize pathogen-associated molecular patterns (PAMPs) that are expressed on infectious agents, and mediate the production of cytokines necessary for the development of effective immunity. The various TLRs exhibit different patterns of expression. This receptor functionally interacts with toll-like receptor 2 to mediate cellular response to bacterial lipoproteins. A Ser249Pro polymorphism in the extracellular domain of the encoded protein may be associated with an increased of asthma is some populations.[provided by RefSeq, Jan 2011]
PHENOTYPE: Inactivation of this gene results in abnormal macrophage function. [provided by MGI curators]
Accession Number

NCBI RefSeq: NM_011604; MGI: 1341296

Mapped Yes 
Amino Acid Change Leucine changed to Stop codon
Institutional SourceBeutler Lab
Ref Sequences
L390* in Ensembl: ENSMUSP00000062096 (fasta)
Gene Model not available
SMART Domains

transmembrane domain 20 39 N/A INTRINSIC
LRR_TYP 86 109 7.67e-2 SMART
Blast:LRR 110 129 N/A BLAST
LRR 131 155 2.76e1 SMART
Blast:LRR 387 410 N/A BLAST
Blast:LRR 413 437 N/A BLAST
LRR 461 482 6.23e1 SMART
LRR 483 507 4.57e0 SMART
LRRCT 540 594 4.06e-11 SMART
transmembrane domain 596 618 N/A INTRINSIC
TIR 652 795 5.37e-37 SMART
Meta Mutation Damage Score Not available question?
Is this an essential gene? Probably nonessential (E-score: 0.158) question?
Phenotypic Category
Phenotypequestion? Literature verified References
immune system
TLR signaling defect: TNF production by macrophages
Candidate Explorer Status CE: no linkage results
Single pedigree
Linkage Analysis Data
Penetrance 100% 
Alleles Listed at MGI

All alleles(5) : Targeted, knock-out(1) Chemically induced(4

Lab Alleles
AlleleSourceChrCoordTypePredicted EffectPPH Score
IGL00949:Tlr6 APN 5 64953512 missense probably damaging 1.00
IGL00963:Tlr6 APN 5 64954676 missense possibly damaging 0.89
IGL01540:Tlr6 APN 5 64955286 missense probably damaging 0.97
IGL01675:Tlr6 APN 5 64954499 missense probably damaging 1.00
IGL01705:Tlr6 APN 5 64954130 missense probably benign 0.03
IGL02256:Tlr6 APN 5 64954944 missense probably benign 0.00
Counterintuitive UTSW 5 64953595 missense probably damaging 1.00
insouciant UTSW 5 64954583 missense possibly damaging 0.81
m2sd1 UTSW 5 64954194 nonsense
m2sd3 UTSW 5 64954241 missense probably damaging 0.98
One_off UTSW 5 64953251 missense probably damaging 1.00
R0336:Tlr6 UTSW 5 64953946 missense probably benign 0.02
R0388:Tlr6 UTSW 5 64955205 missense possibly damaging 0.74
R0558:Tlr6 UTSW 5 64954860 nonsense probably null
R0671:Tlr6 UTSW 5 64954592 missense probably benign 0.00
R1171:Tlr6 UTSW 5 64955250 missense probably benign 0.00
R1550:Tlr6 UTSW 5 64953411 missense probably damaging 0.98
R1809:Tlr6 UTSW 5 64953712 nonsense probably null
R1868:Tlr6 UTSW 5 64954829 missense probably benign 0.00
R1876:Tlr6 UTSW 5 64955420 missense probably damaging 1.00
R1893:Tlr6 UTSW 5 64953213 missense probably damaging 1.00
R2006:Tlr6 UTSW 5 64953405 missense probably damaging 1.00
R2055:Tlr6 UTSW 5 64953926 missense probably damaging 1.00
R3087:Tlr6 UTSW 5 64954325 missense probably damaging 1.00
R3406:Tlr6 UTSW 5 64953429 missense probably damaging 1.00
R3711:Tlr6 UTSW 5 64953809 missense possibly damaging 0.75
R3938:Tlr6 UTSW 5 64953595 missense probably damaging 1.00
R3962:Tlr6 UTSW 5 64954985 missense probably benign 0.10
R4152:Tlr6 UTSW 5 64953212 missense probably damaging 1.00
R4274:Tlr6 UTSW 5 64953638 missense probably benign 0.01
R4516:Tlr6 UTSW 5 64954904 missense possibly damaging 0.67
R4518:Tlr6 UTSW 5 64954904 missense possibly damaging 0.67
R4762:Tlr6 UTSW 5 64954396 missense probably benign 0.09
R4959:Tlr6 UTSW 5 64953659 missense possibly damaging 0.81
R5119:Tlr6 UTSW 5 64954301 missense probably benign 0.06
R5248:Tlr6 UTSW 5 64955304 missense probably benign 0.30
R5507:Tlr6 UTSW 5 64953406 missense probably damaging 1.00
R5572:Tlr6 UTSW 5 64955018 missense probably damaging 1.00
R5773:Tlr6 UTSW 5 64954503 missense probably benign 0.00
R6711:Tlr6 UTSW 5 64954492 missense probably damaging 1.00
R7096:Tlr6 UTSW 5 64953776 missense probably benign
R7341:Tlr6 UTSW 5 64953629 missense probably benign 0.32
R7594:Tlr6 UTSW 5 64953251 missense probably damaging 1.00
R7754:Tlr6 UTSW 5 64954350 missense possibly damaging 0.64
R7774:Tlr6 UTSW 5 64953385 missense probably damaging 0.99
R8292:Tlr6 UTSW 5 64953791 missense probably damaging 1.00
R8348:Tlr6 UTSW 5 64953842 missense probably damaging 1.00
R8376:Tlr6 UTSW 5 64955112 missense probably benign 0.00
R8448:Tlr6 UTSW 5 64953842 missense probably damaging 1.00
Z1177:Tlr6 UTSW 5 64955239 missense probably damaging 0.96
Mode of Inheritance Autosomal Recessive
Local Stock Sperm, gDNA
MMRRC Submission 030960-UCD
Last Updated 2019-01-31 4:58 PM by Stephen Lyon
Record Created unknown
Record Posted 2009-02-03
Phenotypic Description
Figure 1. A, Reduced TNF-α production production (reflected by increased L-929 cell viability) by peritoneal macrophages from the m2sd2 index mouse in response to MALP-2 (red arrow). Responses of other G3 mice are also shown. B, M2sd2 macrophages fail to produce normal levels of TNF-α in response to a range of MALP-2 concentrations. Responses of other G3 mice and the MyD88 mutant pococurante are also shown.

The m2sd2 (MALP-2-specific defect 2) mutant was discovered in a screen of ENU-mutagenized G3 mice for altered responses to Toll-like receptor (TLR) ligands (TLR Signaling Screen). Peritoneal macrophages from the index animal display impaired tumor necrosis factor (TNF)-α production to the TLR2/6 ligand MALP-2 (macrophage-activating lipopeptide-2; Figure 1), but showed normal TNF-α responses to the TLR2/1 ligand Pam3CSK4 (triacyl lipopeptide), the TLR4 ligand lipopolysaccharide (LPS), the TLR9 ligand CpG-DNA (single-stranded DNA), the TLR 7 ligand resiquimod/R-848 (single-stranded RNA mimetic), and the TLR3 ligand poly I:C (double-stranded RNA).  M2sd2 macrophages also responded normally to the TLR2/6 ligand peptidoglycan (PGN); contamination from a TLR1/2 ligand is likely as TLR6-deficient mice responded normally to this ligand, but TLR2-deficient animals did not.

Nature of Mutation
Because the m2sd2 phenotype is almost identical to that of Tlr6-/- mice, Tlr6 (Chromosome 5) from m2sd2 mice was sequenced.  A mutation corresponding to a T to A transversion at position 1301 of the Tlr6 transcript, in exon 2 of 2 total exons, was identified.
385  -S--T--L--K--R--L--Q--T--L--I--L-...
The mutated nucleotide is indicated in red lettering, and results in conversion of a leucine to a stop codon at residue 390 and truncation of 416 amino acids from the C-terminus of the protein.
Illustration of Mutations in
Gene & Protein
Protein Prediction
Figure 2. Protein and domain structure of TLR6. A, Schematic representation of TLR6 based on crystalized structures of mouse TLR3 LRR (PBD 3CIG) and human TLR2 TIR (1FYW) domains. The residue affected by the m2sd2 mutation is highlighted. 3D image was created using UCSF Chimera. B, TLR6 is an 806 amino acid protein with an extracellur domain (pink) of leucine rich repeats (LRR), a short transmembrane domain and a cytoplasmic Toll/Interleukin-1 receptor (TIR) domain. The m2sd2 mutation (red asterisk) results in a conversion of a leucine to a stop codon at residue 390 and truncation of 416 amino acids from the C-terminus of the protein.This image is interactive. Click on the image to view other mutations found in TLR6 (red). Click on the mutations for more specific information.
The m2sd2 mutation results in protein truncation at leucine 390 of the TLR6 protein (Figure 2).  This residue lies near the beginning of the fourteenth leucine rich repeat (LRR).  It is unknown if normal levels of the altered protein are expressed, but truncation would result in a protein missing seven LRR repeats, the transmembrane domain and the Toll/IL-1R (TIR) domain, which binds to adaptor proteins and is necessary for signaling.  
Please see the record for insouciant for information about Tlr6.
Primers Primers cannot be located by automatic search.
M2sd2 genotyping is performed by amplifying the region containing the mutation using PCR, followed by sequencing of the amplified region to detect the single nucleotide change.  The genotyping protocol is the same as for m2sd1
Primers for PCR amplification
PCR program (use SIGMA JumpStart REDTaq)
1) 94°C             2:00
2) 94°C             0:30
3) 56°C             0:30
4) 72°C             1:00
5) repeat steps (2-4) 29X
6) 72°C             7:00
7) 4°C               ∞
Primers for sequencing
The following sequence of 1239 nucleotides (from Genbank genomic region NC_000071 for linear genomic sequence of Tlr6) is amplified:
5405     ggagac agcactgaag tcactgatga tagagcacgt caaaaaccaa gtgttcctct
5461 tttcaaagga ggcgctatac tcggtgtttg ctgagatgaa catcaagatg ctctctatct
5521 cagacacccc tttcatccac atggtgtgcc cgccatcccc aagctcattt acatttctga
5581 actttaccca gaatgttttt actgacagtg tttttcaagg ctgttccacc ttaaagagat
5641 tgcagacact tatcttacaa aggaatggtt tgaagaactt ttttaaagta gctctcatga
5701 ctaagaatat gtcctctctg gaaactttgg atgttagttt gaattctttg aactctcatg
5761 catatgacag gacatgcgcc tgggctgaga gcatattggt gttgaatttg tcttcgaata
5821 tgcttacagg ctctgtcttc agatgcttac ctcccaaggt caaggtcctt gaccttcaca
5881 acaacaggat aatgagcatc cctaaagatg tcacccacct gcaggctttg caggaactca
5941 atgtagcatc caactcctta actgaccttc ctgggtgtgg ggccttcagc agcctttctg
6001 tgctggtcat cgaccataac tcagtttccc atccctctga ggatttcttc cagagctgtc
6061 agaatattag atccctaaca gcgggaaaca acccattcca atgcacatgt gagctgaggg
6121 actttgtcaa gaacataggc tgggtagcaa gagaagtggt ggagggctgg cctgactctt
6181 acaggtgtga ctacccagaa agctctaagg gaactgcact gagggacttc cacatgtctc
6241 cactgtcctg tgatactgtt ctgctgactg tcaccatcgg ggccactatg ctggtgctgg
6301 ctgtcactgg ggctttcctc tgtctctact ttgacctgcc ctggtatgtg aggatgctgt
6361 gtcagtggac acagaccagg cacagggcca ggcacatccc cttagaggaa ctccagagaa
6421 acctccagtt ccatgctttt gtctcataca gtgagcatga ttctgcctgg gtgaagaacg
6481 aattactacc caacctagag aaagatgaca tccgggtttg cctccatgag aggaactttg
6541 tccctggcaa gagcattgtg gagaacatca tcaatttcat tgagaagagt tacaaggcca
6601 tctttgtgct gtctccccac ttcatccaga gtgagtggtg cca
PCR primer binding sites are underlined; sequencing primer binding sites are highlighted in gray; the mutated T is shown in red text.
Science Writers Eva Marie Y. Moresco, Nora G. Smart
Illustrators Diantha La Vine
AuthorsOwen M. Siggs, Bruce Beutler
Edit History
2011-06-01 11:01 AM (current)
2011-01-28 6:54 PM
2010-06-25 11:47 AM
2010-06-25 11:41 AM
2010-06-25 11:41 AM
2010-02-03 5:19 PM