Phenotypic Mutation 'Myd88rev1' (pdf version)
Mutation Type missense
Coordinate119,337,394 bp (GRCm38)
Base Change A ⇒ T (forward strand)
Gene Myd88
Gene Name myeloid differentiation primary response gene 88
Chromosomal Location 119,335,934-119,341,411 bp (-)
MGI Phenotype FUNCTION: [Summary is not available for the mouse gene. This summary is for the human ortholog.] This gene encodes a cytosolic adapter protein that plays a central role in the innate and adaptive immune response. This protein functions as an essential signal transducer in the interleukin-1 and Toll-like receptor signaling pathways. These pathways regulate that activation of numerous proinflammatory genes. The encoded protein consists of an N-terminal death domain and a C-terminal Toll-interleukin1 receptor domain. Patients with defects in this gene have an increased susceptibility to pyogenic bacterial infections. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Feb 2010]
PHENOTYPE: Mice homozygous for a knock-out allele exhibit abnormal immune system morphology and physiology. [provided by MGI curators]
Accession Number

NCBI RefSeq: NM_010851; MGI: 108005

Amino Acid Change Phenylalanine changed to Isoleucine
Institutional SourceBeutler Lab
Gene Model not available
AlphaFold P22366
SMART Domains Protein: ENSMUSP00000035092
Gene: ENSMUSG00000032508
AA Change: F285I

DEATH 19 109 7.17e-15 SMART
TIR 160 296 3.39e-25 SMART
Predicted Effect possibly damaging

PolyPhen 2 Score 0.898 (Sensitivity: 0.82; Specificity: 0.94)
(Using ENSMUST00000035092)
SMART Domains Protein: ENSMUSP00000115746
Gene: ENSMUSG00000032508

Pfam:Death 50 109 3.5e-13 PFAM
Predicted Effect probably benign
Meta Mutation Damage Score Not available question?
Is this an essential gene? Non Essential (E-score: 0.000) question?
Phenotypic Category Unknown
Candidate Explorer Status loading ...
Single pedigree
Linkage Analysis Data
Penetrance unknown 
Alleles Listed at MGI

All alleles(7) : Targeted, knock-out(1) Targeted, other(1) Gene trapped(3) Chemically induced(2)

Lab Alleles
AlleleSourceChrCoordTypePredicted EffectPPH Score
IGL01340:Myd88 APN 9 119337352 unclassified probably benign
Bahia UTSW 9 119338109 splice site probably null
Dani_alves UTSW 9 119337823 missense possibly damaging 0.69
lackadaisical UTSW 9 119338692 missense probably damaging 1.00
pococurante UTSW 9 119338114 missense probably damaging 1.00
R1695:Myd88 UTSW 9 119337842 splice site probably null
R1878:Myd88 UTSW 9 119338620 missense probably benign 0.00
R2413:Myd88 UTSW 9 119337418 missense probably benign 0.06
R3417:Myd88 UTSW 9 119337490 missense possibly damaging 0.90
R3836:Myd88 UTSW 9 119338193 unclassified probably benign
R3892:Myd88 UTSW 9 119337816 missense possibly damaging 0.93
R3917:Myd88 UTSW 9 119341398 utr 5 prime probably benign
R4081:Myd88 UTSW 9 119339987 unclassified probably benign
R4634:Myd88 UTSW 9 119338109 splice site probably null
R4637:Myd88 UTSW 9 119338109 splice site probably null
R5091:Myd88 UTSW 9 119337823 missense possibly damaging 0.69
R5604:Myd88 UTSW 9 119339763 missense possibly damaging 0.93
R9243:Myd88 UTSW 9 119339707 missense probably benign
R9415:Myd88 UTSW 9 119338004 critical splice donor site probably null
Mode of Inheritance Unknown
Local Stock Sperm, gDNA


Last Updated 2017-06-14 10:39 AM by Katherine Timer
Record Created unknown
Record Posted 2010-02-08
Phenotypic Description
The Myd88rev1 allele was discovered in a sequencing screen of G1 mice born to N-ethyl-N-nitrosourea (ENU)-mutagenized sires. DNA collected from animals was sequenced using primers directed against the Myd88 gene. 
Peritoneal macrophages from Myd88rev1 homozygotes were tested in several ex vivo assays. Tumor necrosis factor (TNF)-α production in these macrophages was normal in response to Toll-like receptor (TLR) stimulation including the TLR2/6 ligands MALP2 (macrophage-activating lipopeptide 2) and peptidoglycan (PGN), the TLR9 ligand CpG DNA, the TLR4 ligand lipopolysaccharide (LPS), the TLR1/2 ligand Pam3CSK4 (a triacyl lipopeptide), the TLR7 ligand resiquimod (a ssRNA mimetic), and the TLR3 ligand poly I:C (a dsRNA mimetic) (TLR Signaling Screen). Myd88rev1 macrophages produce normal amounts of double-stranded DNA-induced type I interferon (IFN) (Double-stranded DNA Macrophage Screen), LPS/nigericin-induced interleukin (IL)-1β (NALP3 Inflammasome Screen), and are resistant to infection with mouse cytomegalovirus (MCMV), influenza virus, Rift Valley Fever virus (RVFV), and an adenoviral vector (Ex Vivo Macrophage Screen for Control of Viral Infection).
Nature of Mutation
The Myd88rev1 mutation is a T to A transversion identified in exon 5 (of 6 total exons) at position 934 of the Myd88 transcript.
280 -C--T--K--S--W--F--W--T--R--L--A-
The mutated nucleotide is indicated in red lettering, and results in a conversion of phenylalanine to isoleucine at residue 285 of the MyD88 protein.
Illustration of Mutations in
Gene & Protein
Protein Prediction
Figure 1. Solution structure of the MyD88 TIR domain. The central five β-strands are shown in cyan while the surrounding α-helices are shown in pink. The BB loop important for MyD88 binding to TLRs, and the αE helix important for homotypic interactions, are labeled. The amino acid altered by the Myd88rev1 mutation is indicated. UCSF Chimera structure is based on PDB 2Z5V, Ohnishi et al, Proc. Natl. Acad. Sci. U.S.A. 106, 10260-10265 (2009). Click on the 3D structure to view it rotate.
Figure 2. MyD88 domain structure and 3D TIR domain. A, MyD88 is a 296 amino acid protein adapter. It contains an N-terminal death domain (DD) that acts as a protein-protein interaction domain that mediates homotypic interactions with other death domain-containing proteins in order to propagate signaling. The death domain of MyD88 is required for binding to IL-1 receptor associated kinase (IRAK) family proteins. The C-terminal portion of MyD88 contains a Toll/IL-1 receptor (TIR) domain, a conserved region which mediates homo- and heterotypic protein interactions during signal transduction. TIR domains in TLRs, IL receptors and the adapters MyD88 and TIRAP contain three conserved boxes (boxes 1, 2 and 3), which are required for signaling. Between the death domain and TIR domain is an “intermediate domain” that may be required for differential activation of distinct NF-κB- versus JNK-dependent transcriptional programs. The Myd88rev mutation results in a substitution of a highly conserved phenylalanine with isoleucine at residue 285. B, The 3D structure shows the six α-helices and five β-strands of the TIR domain. 3D structure was created using UCSF Chimera package (2Z5V). This image is interactive. Click on the image to view other mutations found in MyD88 (red). Click on the mutations for more specific information. Click on the 3D structure to view it rotate.
The Myd88rev1 mutation results in substitution of an isoleucine for a highly conserved phenylalanine at residue 285 of MyD88 located in the αE helix of the MyD88 TIR domain (Figures 1 and 2).
Please see the record for pococurante for information about Myd88.
Putative Mechanism
Figure 3. MyD88 signaling pathways. MyD88 is a protein adapter that relays signals from the IL-1 and IL-8 receptors (not shown) and from most TLRs. Activation of these receptors leads to MyD88 recruitment to the receptor complexes, where it recruits IRAK family proteins, first IRAK-4 and then IRAK-1, as well as TRAF6. The signaling pathway culminates in the activation of NF-κB-dependent transcription. MyD88 and TRAF6 may interact directly with IRF5 in a complex, activating IRF5 and promoting its translocation to the nucleus. MyD88, together with TRAF6 and IRAK4, has also been shown to bind IRF7 directly. This occurs downstream of TLR7, TLR8 and TLR9 in plasmacytoid dendritic cells and requires the phosphorylation of IRF7 by IRAK1.
The αE helix of the MyD88 TIR domain is known to participate in important protein-protein interactions critical for MyD88 function. In particular, the αE helix has been proposed to contribute to homotypic oligomerization of TIR domains, which is necessary for the propagation of signal from the MyD88 receptor to more distal elements of the TLR signaling pathway (Figure 3). Mutation of two conserved amino acids to two alanines within the αE helix of either TLR2 or MyD88 prevents ligand-induced NF-κB activation in vitro (1,2), but does not prevent the association of MyD88 with TLRs suggesting that these residues instead affect homotypic interactions. Interestingly, one of the amino acids mutated in these studies is F285, the same residue affected by the Myd898rev1 mutation. Clearly, mutating this residue to an isoleucine has no effect on the function of MyD88 in vivo. As the previous in vitro studies analyzed the effects of mutating both F285 and W286 at the same time, it is likely that W286, not F285, is the critical amino acid responsible for mediating homotypic TIR interactions despite the high conservation of both of these residues or that both of these residues need to be altered in order to affect function. It is also possible that the alanine substitution at amino acid 285 has more impact than substitution with an isoleucine.
Primers Primers cannot be located by automatic search.
Myd88rev1 genotyping is performed by amplifying the region containing the mutation using PCR, followed by sequencing of the amplified region to detect the single nucleotide transition. 
PCR program
1) 95°C             2:00
2) 95°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
Myd88rev1_seq(F): 5'- CATTGCCAGCGAGCTAATTGAG -3'
Myd88rev1_seq(R): 5’- GCCCTGATAAACACTGTCCTG -3’
The following sequence of 1006 nucleotides (NCBI Mouse Genome Build 37.1, Chromosome 9, bases 119,246,239 to 119,247,244) is amplified:
agatgatccg gcaactagaa cagacagact atcggcttaa gttgtgtgtg tccgaccgtg
acgtcctgcc gggcacctgt gtctggtcca ttgccagcga gctaattgag aaaaggttgg
ttaaacatct aagagggtag gtgggtgaat gcatgaaacc cagaggtcca gatgcaagga
ctgtcctgct agctgggctc tgtcccgcct gggtaatgta gtccttcctg accccatcct
ctgaaggaag tcaccgcagt gccactctcc ctcaggtgtc gccgcatggt ggtggttgtt
tctgacgatt atctacagag caaggaatgt gacttccaga ccaagtttgc actcagcctg
tctccaggta agcttaggcc tgctttggtc aaagagagag tagagatata gccttaggat
gatagtccag gaatgcaaaa ccaaagcact acagatctct gaggacggac ctgtgtactt
ccttatgtag tggatatgta tcatggatac ctggttggtg gagagctggt gttagcccgt
gctttaggga ctgagcctgt cccaccctag ggccccacgt ggtcctaata ccacaccctt
tggccttcag gtgtccaaca gaagcgactg attcctatta aatacaaggc gatgaagaag
gactttccca gtatcctgcg gttcatcact atatgcgact ataccaaccc ttgcaccaag
tcctggttct ggacccgcct tgccaaggct ttgtccctgc cctgaagatg accctgggag
ccctaggtat gtcagtctgt ctgtgttctt ccgcttgcct cctttgacac tgtagtgggg
agcttgtggt ccgtctatcc ctagacatct acagtagcca gatgtcatct ctcaagtcct
tacggaacca gtgactgcaa gtgacattat gacttgccgg gttgccagcc aggacagtgt
ttatcagggc tgcatgagtc taagcgaagg actagttgag
Primer binding sites are underlined; sequencing primer binding sites are highlighted in gray; the mutated T is indicated in red.
Science Writers Nora G. Smart
Illustrators Diantha La Vine, Katherine Timer
AuthorsKevin Khovananth, Owen Siggs, Yu Xia and Bruce Beutler
Edit History
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