Mutagenetix > Incidental Mutation

Incidental Mutation 'H8930:Mtr'

538

Institutional Source

Beutler Lab

Gene Symbol

Mtr

Ensembl Gene

ENSMUSG00000021311

Gene Name

5-methyltetrahydrofolate-homocysteine methyltransferase

Synonyms

methionine synthase, D830038K18Rik, MS

Accession Numbers

Essential gene?

Essential (E-score: 1.000) question?

Stock #

H8930 (G3) of strain frazz

Quality Score

Status

Validated

Chromosome

Chromosomal Location

12197598-12272999 bp(-) (GRCm39)

Type of Mutation

missense

DNA Base Change (assembly)

A to G at 12250346 bp (GRCm39)

Zygosity

Heterozygous

Amino Acid Change

Serine to Proline at position 346 (S346P)

Ref Sequence

ENSEMBL: ENSMUSP00000097442 (fasta)

Gene Model

predicted gene model for transcript(s): [ENSMUST00000099856] [ENSMUST00000221290]

AlphaFold

A6H5Y3

Predicted Effect

probably damaging
Transcript: ENSMUST00000099856
AA Change: S346P

PolyPhen 2 Score 0.999 (Sensitivity: 0.14; Specificity: 0.99)

SMART Domains

Protein: ENSMUSP00000097442
Gene: ENSMUSG00000021311
AA Change: S346P

Domain	Start	End	E-Value	Type
Pfam:S-methyl_trans	18	326	1.5e-93	PFAM
Pfam:Pterin_bind	363	601	4.6e-63	PFAM
B12-binding_2	657	743	6.42e-41	SMART
Pfam:B12-binding	761	861	3.3e-20	PFAM
Pfam:Met_synt_B12	953	1234	2.5e-114	PFAM

Predicted Effect

probably benign
Transcript: ENSMUST00000221290

Meta Mutation Damage Score

0.7306

Coding Region Coverage

1x: 77.1%
3x: 50.6%

Het Detection Efficiency

25.5%

Validation Efficiency

74% (89/120)

MGI Phenotype

FUNCTION: [Summary is not available for the mouse gene. This summary is for the human ortholog.] This gene encodes the 5-methyltetrahydrofolate-homocysteine methyltransferase. This enzyme, also known as cobalamin-dependent methionine synthase, catalyzes the final step in methionine biosynthesis. Mutations in MTR have been identified as the underlying cause of methylcobalamin deficiency complementation group G. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, May 2014]
PHENOTYPE: Mice homozygous for a targeted null mutation exhibit embryonic lethality prior to E9.5. Heterozygous appear mostly similar to conrtols, except that they exhibit elevated plasma methionine and homocysteine levels. [provided by MGI curators]

Allele List at MGI

All alleles(6) : Targeted, knock-out(1) Gene trapped(5)

Other mutations in this stock

Total: 7 list
Gene	Ref	Var	Chr/Loc	Mutation	Predicted Effect	Zygosity
Cdc20b	A	T	13: 113,220,500 (GRCm39)	I460F	probably damaging	Homo
Cilk1	T	A	9: 78,057,901 (GRCm39)	I150N	possibly damaging	Het
Ddx4	A	C	13: 112,750,367 (GRCm39)		probably null	Homo
Malt1	T	G	18: 65,595,886 (GRCm39)	Y442*	probably null	Het
Nup155	T	C	15: 8,187,142 (GRCm39)	V1357A	possibly damaging	Het
Prl3c1	T	A	13: 27,384,689 (GRCm39)	L46*	probably null	Het
Spata1	A	T	3: 146,193,026 (GRCm39)	L155*	probably null	Homo

Other mutations in Mtr

Allele	Source	Chr	Coord	Type	Predicted Effect	PPH Score
IGL01299:Mtr	APN	13	12,240,536 (GRCm39)	splice site	probably benign
IGL02456:Mtr	APN	13	12,213,980 (GRCm39)	missense	probably damaging	0.98
IGL02573:Mtr	APN	13	12,214,013 (GRCm39)	missense	possibly damaging	0.95
IGL02642:Mtr	APN	13	12,210,118 (GRCm39)	splice site	probably benign
IGL03005:Mtr	APN	13	12,250,335 (GRCm39)	splice site	probably benign
IGL03017:Mtr	APN	13	12,262,777 (GRCm39)	critical splice donor site	probably null
IGL03036:Mtr	APN	13	12,262,263 (GRCm39)	missense	probably damaging	1.00
PIT4431001:Mtr	UTSW	13	12,227,329 (GRCm39)	missense	probably damaging	1.00
PIT4520001:Mtr	UTSW	13	12,212,871 (GRCm39)	nonsense	probably null
R0011:Mtr	UTSW	13	12,252,938 (GRCm39)	splice site	probably benign
R0047:Mtr	UTSW	13	12,237,112 (GRCm39)	missense	probably damaging	1.00
R0047:Mtr	UTSW	13	12,237,112 (GRCm39)	missense	probably damaging	1.00
R0304:Mtr	UTSW	13	12,237,040 (GRCm39)	critical splice donor site	probably null
R0617:Mtr	UTSW	13	12,236,318 (GRCm39)	missense	probably benign
R0842:Mtr	UTSW	13	12,215,133 (GRCm39)	missense	probably damaging	1.00
R1101:Mtr	UTSW	13	12,204,411 (GRCm39)	missense	possibly damaging	0.84
R1450:Mtr	UTSW	13	12,208,619 (GRCm39)	missense	probably damaging	0.99
R1534:Mtr	UTSW	13	12,250,430 (GRCm39)	splice site	probably benign
R1907:Mtr	UTSW	13	12,240,418 (GRCm39)	missense	probably damaging	1.00
R2111:Mtr	UTSW	13	12,259,487 (GRCm39)	missense	possibly damaging	0.86
R2354:Mtr	UTSW	13	12,203,043 (GRCm39)	splice site	probably benign
R3849:Mtr	UTSW	13	12,262,251 (GRCm39)	missense	probably benign	0.16
R3899:Mtr	UTSW	13	12,231,735 (GRCm39)	missense	probably benign	0.00
R4012:Mtr	UTSW	13	12,204,284 (GRCm39)	missense	probably damaging	1.00
R4012:Mtr	UTSW	13	12,204,283 (GRCm39)	missense	probably damaging	1.00
R4075:Mtr	UTSW	13	12,230,298 (GRCm39)	critical splice donor site	probably null
R4091:Mtr	UTSW	13	12,245,943 (GRCm39)	missense	probably damaging	1.00
R4655:Mtr	UTSW	13	12,242,679 (GRCm39)	missense	probably damaging	1.00
R4801:Mtr	UTSW	13	12,210,137 (GRCm39)	missense	probably benign	0.01
R4802:Mtr	UTSW	13	12,210,137 (GRCm39)	missense	probably benign	0.01
R4895:Mtr	UTSW	13	12,231,752 (GRCm39)	missense	probably benign	0.01
R5481:Mtr	UTSW	13	12,203,041 (GRCm39)	critical splice acceptor site	probably null
R5966:Mtr	UTSW	13	12,230,453 (GRCm39)	critical splice acceptor site	probably null
R6209:Mtr	UTSW	13	12,205,278 (GRCm39)	missense	probably benign	0.00
R6348:Mtr	UTSW	13	12,262,840 (GRCm39)	missense	possibly damaging	0.49
R6463:Mtr	UTSW	13	12,231,752 (GRCm39)	missense	probably benign	0.01
R6467:Mtr	UTSW	13	12,202,992 (GRCm39)	missense	probably damaging	1.00
R7046:Mtr	UTSW	13	12,205,095 (GRCm39)	missense	possibly damaging	0.58
R7505:Mtr	UTSW	13	12,236,362 (GRCm39)	missense	probably benign	0.02
R7575:Mtr	UTSW	13	12,213,963 (GRCm39)	missense	probably benign	0.01
R7705:Mtr	UTSW	13	12,264,782 (GRCm39)	missense	probably benign
R7748:Mtr	UTSW	13	12,242,725 (GRCm39)	missense	probably benign	0.00
R8161:Mtr	UTSW	13	12,236,372 (GRCm39)	missense	probably damaging	0.99
R8290:Mtr	UTSW	13	12,205,139 (GRCm39)	missense	probably damaging	1.00
R8988:Mtr	UTSW	13	12,250,365 (GRCm39)	missense	probably benign
R9050:Mtr	UTSW	13	12,231,748 (GRCm39)	missense	probably null	0.67
R9420:Mtr	UTSW	13	12,268,764 (GRCm39)	missense	probably benign	0.04
R9655:Mtr	UTSW	13	12,203,030 (GRCm39)	missense	probably damaging	1.00
X0064:Mtr	UTSW	13	12,265,543 (GRCm39)	missense	probably damaging	1.00
Z1177:Mtr	UTSW	13	12,264,752 (GRCm39)	nonsense	probably null
Z1177:Mtr	UTSW	13	12,201,935 (GRCm39)	missense	probably benign	0.32

Nature of Mutation

DNA sequencing using the SOLiD technique identified a T to C transition at position 1180 of the Mtr transcript in exon 12 of 33 total exons. Two transcripts of the Mtr gene are displayed on Ensembl. The mutated nucleotide causes a serine to proline substitution at amino acid 346 of the encoded protein. The mutation has been confirmed by DNA sequencing using the Sanger method (Figure 1).

Protein Function and Prediction

The Mtr gene encodes a 1253 amino acid enzyme that catalyzes the transfer of a methyl group from methyl-cobalamin to homocysteine, yielding enzyme-bound cob(I)alamin and methionine. The protein subsequently remethylates the cofactor using methyltetrahydrofolate. 5-methyltetrahydrofolate-homocysteine S-methyltransferase is a modular enzyme with four distinct domains. The isolated Hcy-binding domain (residues 6-326) catalyzes methyl transfer from free methylcobalamin to homocysteine. The Hcy-binding domain in association with the pterin-binding domain (residues 359-620) catalyzes the methylation of cob(I)alamin by methyltetrahydrofolate and the methylation of homocysteine. The B12-binding domain (residues 650-895) binds the cofactor. The AdoMet activation domain (residues 911-1253) binds S-adenosyl-L-methionine (Uniprot A6H5Y3). Mice homozygous for a targeted null mutation exhibit embryonic lethality prior to E9.5. Heterozygous mice appear mostly similar to controls, except that they exhibit elevated plasma methionine and homocysteine levels. Mutations in the human gene cause cblG disorder (OMIM 250940) with mental retardation, macrocytic anemia, and homocystinuria.

The S346P change is located between the Hcy-binding domain and the pterin-binding domain, and is predicted to be probably damaging by the PolyPhen program.

Posted On

2010-11-11