Incidental Mutation 'R0009:Cntn2'
Institutional Source Beutler Lab
Gene Symbol Cntn2
Ensembl Gene ENSMUSG00000053024
Gene Namecontactin 2
Synonymsaxonin, Tax, TAG-1, D130012K04Rik
MMRRC Submission 038304-MU
Accession Numbers

Ncbi RefSeq: NM_177129.5; MGI:104518

Is this an essential gene? Probably non essential (E-score: 0.212) question?
Stock #R0009 (G1)
Quality Score
Status Validated
Chromosomal Location132509427-132543256 bp(-) (GRCm38)
Type of Mutationnonsense
DNA Base Change (assembly) G to A at 132516180 bp
Amino Acid Change Glutamine to Stop codon at position 457 (Q457*)
Gene Model predicted gene model for transcript(s): [ENSMUST00000086521]
Predicted Effect probably null
Transcript: ENSMUST00000086521
AA Change: Q954*
SMART Domains Protein: ENSMUSP00000083707
Gene: ENSMUSG00000053024
AA Change: Q954*

signal peptide 1 28 N/A INTRINSIC
IGc2 54 120 8.78e-9 SMART
IG 142 232 3.89e-1 SMART
IGc2 254 315 2.14e-21 SMART
IGc2 341 404 4.59e-12 SMART
IGc2 433 497 7.52e-8 SMART
IGc2 523 596 2.72e-5 SMART
FN3 610 696 2.72e-12 SMART
FN3 713 799 1.02e-2 SMART
FN3 815 899 5.27e-10 SMART
FN3 915 995 8.91e1 SMART
Predicted Effect noncoding transcript
Transcript: ENSMUST00000186487
Predicted Effect probably null
Transcript: ENSMUST00000188065
AA Change: Q457*
Predicted Effect noncoding transcript
Transcript: ENSMUST00000188143
Predicted Effect probably benign
Transcript: ENSMUST00000189528
Predicted Effect noncoding transcript
Transcript: ENSMUST00000190601
Meta Mutation Damage Score 0.9754 question?
Coding Region Coverage
  • 1x: 79.7%
  • 3x: 70.1%
  • 10x: 44.5%
  • 20x: 24.1%
Validation Efficiency 93% (78/84)
MGI Phenotype Strain: 2181052; 2677610; 3521785
FUNCTION: This gene encodes a member of the contactin family of proteins, part of the immunoglobulin superfamily of cell adhesion molecules. The encoded glycosylphosphatidylinositol (GPI)-anchored neuronal membrane protein plays a role in the proliferation, migration, and axon guidance of neurons of the developing cerebellum. Mice lacking a functional copy of this gene exhibit epileptic seizures and elevated expression of A1 adenosine receptors. [provided by RefSeq, Sep 2016]
PHENOTYPE: Targeted mutation of this locus results in molecular abnormalities in the central nervous system. [provided by MGI curators]
Allele List at MGI

All alleles(5) : Targeted(5)

Other mutations in this stock
Total: 29 list
GeneRefVarChr/LocMutationPredicted EffectZygosity
A1bg T G 15: 60,919,633 probably benign Het
Afm C A 5: 90,545,384 probably benign Het
Aplnr T A 2: 85,137,276 probably null Het
Arih2 T A 9: 108,611,727 H264L probably damaging Het
Ccdc116 T C 16: 17,144,039 E15G probably damaging Het
Cfap53 A G 18: 74,299,176 H45R probably benign Het
Chd3 A G 11: 69,349,906 L1569P probably damaging Het
Coro1a A T 7: 126,701,413 probably benign Het
Cracr2b T A 7: 141,463,759 L91Q probably damaging Het
Ctdspl T C 9: 119,020,046 probably null Het
Dnase1 T C 16: 4,038,946 V147A probably damaging Het
Glud1 G A 14: 34,334,268 G300S probably benign Het
Gm4847 C T 1: 166,630,486 V433I probably benign Het
Herc2 T C 7: 56,207,812 S4048P probably benign Het
Hp1bp3 T A 4: 138,221,683 I19K probably benign Het
Il1a C T 2: 129,309,074 D10N probably damaging Het
Il22ra2 A T 10: 19,624,458 N39I probably damaging Het
Magi2 A T 5: 20,611,055 Y747F probably benign Het
Mcc C T 18: 44,445,933 E803K probably damaging Het
Rims2 T A 15: 39,534,966 M1087K probably damaging Het
Riox2 C A 16: 59,489,367 D361E probably benign Het
Slc35e1 A T 8: 72,484,709 N318K probably damaging Het
Slc9a2 A T 1: 40,763,602 E604V probably benign Het
Tbx19 A T 1: 165,160,520 S15T possibly damaging Het
Tm4sf5 C T 11: 70,510,712 A179V probably damaging Het
Trappc11 A T 8: 47,503,320 C874S possibly damaging Het
Trpm3 T A 19: 22,914,446 Y885N probably damaging Het
Unc5a T A 13: 55,002,879 C505S probably damaging Het
Xpo5 T C 17: 46,204,786 probably benign Het
Other mutations in Cntn2
AlleleSourceChrCoordTypePredicted EffectPPH Score
IGL01106:Cntn2 APN 1 132521884 splice site probably benign
IGL01137:Cntn2 APN 1 132521297 splice site probably benign
IGL01339:Cntn2 APN 1 132518905 splice site probably null
IGL01369:Cntn2 APN 1 132516105 missense probably benign
IGL01572:Cntn2 APN 1 132528171 missense probably damaging 1.00
IGL02389:Cntn2 APN 1 132525321 missense probably damaging 0.99
IGL02473:Cntn2 APN 1 132518331 missense probably benign
IGL02550:Cntn2 APN 1 132529063 missense probably null 0.03
IGL02608:Cntn2 APN 1 132525916 missense possibly damaging 0.87
IGL02755:Cntn2 APN 1 132529302 missense probably benign 0.43
IGL02850:Cntn2 APN 1 132518376 missense probably benign 0.00
IGL02887:Cntn2 APN 1 132516570 missense probably damaging 0.96
IGL03060:Cntn2 APN 1 132528940 missense probably benign 0.03
IGL03224:Cntn2 APN 1 132523042 missense probably damaging 1.00
R0009:Cntn2 UTSW 1 132516180 nonsense probably null
R0270:Cntn2 UTSW 1 132521724 missense probably damaging 1.00
R0739:Cntn2 UTSW 1 132529012 missense probably damaging 1.00
R0849:Cntn2 UTSW 1 132522386 missense probably benign 0.09
R0903:Cntn2 UTSW 1 132533684 small deletion probably benign
R1463:Cntn2 UTSW 1 132521137 critical splice donor site probably null
R1512:Cntn2 UTSW 1 132523692 missense probably damaging 0.99
R1535:Cntn2 UTSW 1 132525384 missense probably benign 0.26
R1686:Cntn2 UTSW 1 132526311 missense possibly damaging 0.78
R1696:Cntn2 UTSW 1 132521279 missense probably damaging 0.96
R1708:Cntn2 UTSW 1 132519198 missense probably damaging 0.96
R2251:Cntn2 UTSW 1 132525321 missense probably damaging 0.99
R2315:Cntn2 UTSW 1 132522997 missense probably benign 0.00
R2395:Cntn2 UTSW 1 132526372 missense probably benign
R3617:Cntn2 UTSW 1 132528623 missense probably benign 0.16
R3883:Cntn2 UTSW 1 132528939 missense probably damaging 0.99
R3884:Cntn2 UTSW 1 132528939 missense probably damaging 0.99
R4060:Cntn2 UTSW 1 132525896 missense probably damaging 0.99
R4289:Cntn2 UTSW 1 132527743 missense probably benign 0.01
R4710:Cntn2 UTSW 1 132528225 missense possibly damaging 0.84
R4921:Cntn2 UTSW 1 132516032 missense possibly damaging 0.49
R5121:Cntn2 UTSW 1 132517060 nonsense probably null
R5288:Cntn2 UTSW 1 132523677 missense probably benign 0.18
R5360:Cntn2 UTSW 1 132518857 missense probably damaging 0.97
R5787:Cntn2 UTSW 1 132523059 missense probably damaging 1.00
R5817:Cntn2 UTSW 1 132518748 missense probably benign 0.21
R5930:Cntn2 UTSW 1 132523432 missense probably damaging 1.00
R6053:Cntn2 UTSW 1 132518352 missense probably benign 0.18
R7189:Cntn2 UTSW 1 132517086 missense probably damaging 1.00
R7352:Cntn2 UTSW 1 132522399 missense probably benign 0.02
R7562:Cntn2 UTSW 1 132526317 missense possibly damaging 0.67
R7689:Cntn2 UTSW 1 132516144 missense probably benign 0.00
R7764:Cntn2 UTSW 1 132522363 missense probably benign 0.21
R8080:Cntn2 UTSW 1 132521798 missense probably damaging 1.00
R8344:Cntn2 UTSW 1 132521774 missense probably damaging 1.00
R8683:Cntn2 UTSW 1 132522993 missense probably damaging 1.00
X0018:Cntn2 UTSW 1 132533684 small deletion probably benign
Z1176:Cntn2 UTSW 1 132527788 missense probably damaging 1.00
Protein Function and Prediction

Cntn2 encodes the transiently-expressed axonal glycoprotein 1 (TAG1; alternatively TAX1), a cell adhesion immunoglobulin in the contractin family that functions in neurite outgrowth (1-4).  In addition to its function in outgrowth, TAG1 is also proposed to function in the guidance and fasciculation of neurites (4;5). It is proposed that TAG1 functions in the initial extension of developing axons within the rodent spinal cord (1). Neurocan and phosphacan/protein-tyrosine phosphatase-η/β are the ligands of TAG1 (2). TAG1 and Caspr2 form a scaffold that functions to maintain K+ channels at the juxtaparanodal region (6).


TAG1 is transiently expressed on subsets of embryonic spinal cord axons (early motor and commissural axons) and growth cones in the developing brain (4;7). Schwann cells and oligodendrocytes also express TAG1 throughout life (8).


Cntn2tm1Fuka/tm1Fuka; MGI:2181052

involves: 129S1/Sv * 129X1/SvJ * C57BL/6

The morphology of the cerebellum, spinal cord and hippocampus in the homozygous mice are grossly normal (5). Homozygous animals had an upregulation of adenosine A1 receptors in the hippocampus and exhibited greater sensitivity to convulsant stimuli than wild-type animals (5).


Savvaki et al. show that mice with depletion in Tag1 have impaired learning and memory, as well as sensory and motor dysfunction (4). They also observe impairment of juxtaparanodal organization, shortening of internodes and altered VGKC and Caspr2 levels (4). Homozygotes also underperformed in the Morris water maze (MWM) and novel object recognition tests, and also showing reduced spontaneous motor activity, abnormal gait coordination and increased response latency to noxious thermal stimulation (hot-plate test) (4). The molecular organization of juxtaparanodal areas was disrupted and the internodes were shortened in relevant brain areas involved in learning and memory function, coordination, as well as excitability (4).


Cntn2tm1Furl/tm1Furl; MGI:2677610

involves: 129S1/Sv

In homozygous animals, axons are insensitive to wild-type ventral spinal cord (VSC)-derived chemorepellants, abnormal sensory neuron projections, and abnormal spinal cord dorsal horn morphology (9).


Cntn2tm1Furl/tm1Furl; MGI:2677610

involves: 129S1/Sv * C57BL/6

The phenotype of mice in this genetic background are similar to the ones listed above (9).


Cntn2tm2Furl/tm2Furl; MGI:3521785


Homozygotes in this model have abnormal somatic nervous system physiology in that cultured dorsal root ganglion cells have much less repulsion to ventral spinal cord explants than controls (9).

Posted On2012-11-20
Science WriterAnne Murray