Phenotypic Mutation 'barrener' (pdf version)
Allelebarrener
Mutation Type critical splice donor site
Chromosome9
Coordinate96,011,149 bp (GRCm39)
Base Change T ⇒ C (forward strand)
Gene Gk5
Gene Name glycerol kinase 5
Synonym(s) G630067D24Rik, C330018K18Rik
Chromosomal Location 96,001,415-96,066,661 bp (+) (GRCm39)
MGI Phenotype PHENOTYPE: Homozygous knockout does not result in an obvious skin phenotype and does not lead to alopecia. [provided by MGI curators]
Accession Number

NCBI RefSeq: NM_177352; MGI:2443336

MappedYes 
Amino Acid Change
Institutional SourceBeutler Lab
Gene Model predicted gene model for protein(s): [ENSMUSP00000082313 ] [ENSMUSP00000112717 ] [ENSMUSP00000123594]   † probably from a misspliced transcript
AlphaFold Q8BX05
SMART Domains Protein: ENSMUSP00000082313
Gene: ENSMUSG00000041440

DomainStartEndE-ValueType
low complexity region 4 20 N/A INTRINSIC
Pfam:FGGY_N 25 287 9e-50 PFAM
Pfam:FGGY_C 296 485 7.7e-35 PFAM
Predicted Effect probably null
SMART Domains Protein: ENSMUSP00000112717
Gene: ENSMUSG00000041440

DomainStartEndE-ValueType
low complexity region 4 20 N/A INTRINSIC
Pfam:FGGY_N 25 287 1.9e-49 PFAM
Pfam:FGGY_C 296 485 1.8e-35 PFAM
Predicted Effect probably null
SMART Domains Protein: ENSMUSP00000123594
Gene: ENSMUSG00000041440

DomainStartEndE-ValueType
low complexity region 4 20 N/A INTRINSIC
SCOP:d1bu6o1 24 56 1e-5 SMART
Predicted Effect probably benign
Meta Mutation Damage Score 0.9499 question?
Is this an essential gene? Non Essential (E-score: 0.000) question?
Phenotypic Category Autosomal Recessive
Candidate Explorer Status loading ...
Single pedigree
Linkage Analysis Data
Penetrance  
Alleles Listed at MGI

All Mutations and Alleles(20) : Chemically induced (other)(1) Gene trapped(17) Targeted(2)

Lab Alleles
AlleleSourceChrCoordTypePredicted EffectPPH Score
IGL01359:Gk5 APN 9 96019842 missense probably damaging 0.98
IGL01387:Gk5 APN 9 96059607 critical splice donor site probably null
IGL01771:Gk5 APN 9 96059488 missense probably damaging 0.97
IGL02253:Gk5 APN 9 96019824 missense probably damaging 1.00
IGL02380:Gk5 APN 9 96032533 missense possibly damaging 0.92
IGL02566:Gk5 APN 9 96011099 missense possibly damaging 0.56
IGL03137:Gk5 APN 9 96058345 splice site probably benign
IGL03256:Gk5 APN 9 96011106 missense probably damaging 1.00
IGL03326:Gk5 APN 9 96019892 critical splice donor site probably null
glimpse UTSW 9 96063823 critical splice acceptor site probably null
homer UTSW 9 96022709 nonsense probably null
sean UTSW 9 96058290 nonsense probably null
stripped UTSW 9 96011106 missense probably damaging 1.00
tangyuan UTSW 9 96032850 critical splice donor site probably null
toku UTSW 9 96022682 frame shift probably null
victoria UTSW 9 96032839 missense possibly damaging 0.65
G1patch:Gk5 UTSW 9 96037523 missense probably benign 0.01
I1329:Gk5 UTSW 9 96022682 frame shift probably null
R0279:Gk5 UTSW 9 96056857 splice site probably benign
R0284:Gk5 UTSW 9 96063823 critical splice acceptor site probably null
R1134:Gk5 UTSW 9 96015460 missense probably benign 0.00
R1184:Gk5 UTSW 9 96032473 splice site probably benign
R1772:Gk5 UTSW 9 96032850 critical splice donor site probably null
R1781:Gk5 UTSW 9 96015508 missense possibly damaging 0.79
R3691:Gk5 UTSW 9 96011149 critical splice donor site probably null
R4213:Gk5 UTSW 9 96011106 missense probably damaging 1.00
R5015:Gk5 UTSW 9 96059470 critical splice acceptor site probably null
R5166:Gk5 UTSW 9 96056821 missense probably damaging 0.99
R5643:Gk5 UTSW 9 96022709 nonsense probably null
R5857:Gk5 UTSW 9 96001508 nonsense probably null
R5924:Gk5 UTSW 9 96032563 critical splice donor site probably null
R6109:Gk5 UTSW 9 96022663 missense probably benign 0.00
R6138:Gk5 UTSW 9 96058290 nonsense probably null
R6725:Gk5 UTSW 9 96037523 missense probably benign 0.01
R6812:Gk5 UTSW 9 96032802 missense probably damaging 0.99
R7065:Gk5 UTSW 9 96061109 missense probably damaging 1.00
R7182:Gk5 UTSW 9 96001579 missense possibly damaging 0.89
R7213:Gk5 UTSW 9 96027765 missense probably damaging 1.00
R7260:Gk5 UTSW 9 96001663 missense probably benign 0.10
R7607:Gk5 UTSW 9 96035263 splice site probably null
R7666:Gk5 UTSW 9 96035160 missense probably damaging 1.00
R8152:Gk5 UTSW 9 96056756 missense probably damaging 1.00
R8355:Gk5 UTSW 9 96032839 missense possibly damaging 0.65
R8954:Gk5 UTSW 9 96059562 missense probably benign 0.07
R9077:Gk5 UTSW 9 96001634 missense probably benign 0.00
R9186:Gk5 UTSW 9 96015469 missense probably benign 0.44
U15987:Gk5 UTSW 9 96058290 nonsense probably null
Mode of Inheritance Autosomal Recessive
Local Stock
Repository
Last Updated 2019-09-04 9:44 PM by Anne Murray
Record Created 2015-10-14 5:19 PM by Zhao Zhang
Record Posted 2017-05-25
Phenotypic Description

Figure 1. Barrener mice (right) exhibited hair loss. A wild-type litter mate is shown on the left for reference.

Figure 2. Barrener mice exhibit increased frequencies of peripheral CD44+ CD8 T cells. Flow cytometric analysis of peripheral blood was utilized to determine T cell frequency. Normalized data are shown. Abbreviations: WT, wild-type; REF, homozygous reference mice; HET, heterozygous variant mice; VAR, homozygous variant mice. Mean (μ) and standard deviation (σ) are indicated.

The barrener phenotype was identified among N-ethyl-N-nitrosourea (ENU)-mutagenized G3 mice of the pedigree R3691, some of which showed hair loss (Figure 1). Some mice also showed increased frequencies of peripheral blood CD44+ CD8 T cells (Figure 1).

Nature of Mutation

Figure 3. Linkage mapping of the hair loss phenotype using a recessive model of inheritance. Manhattan plot shows -log10 P values (Y-axis) plotted against the chromosome positions of 35 mutations (X-axis) identified in the G1 male of pedigree R3691. Binary phenotype data are shown for single locus linkage analysis without consideration of G2 dam identity. Horizontal pink and red lines represent thresholds of P = 0.05, and the threshold for P = 0.05 after applying Bonferroni correction, respectively.

Whole exome HiSeq sequencing of the G1 grandsire identified 35 mutations. Both of the above anomalies were linked to a mutation in Gk5: a T to C transition at base pair 96,129,096 (v38) on chromosome 9, or base pair 9,753 in the GenBank genomic region NC_000075 in the splice donor site of intron 2. The strongest association was found with a recessive model of inheritance (P = 3.307 x 10-8) to the CD44+ CD8 T cell phenotype, wherein six affected mice were homozygous (N = 6) for the variant allele, and 39 unaffected mice were either heterozygous (N = 23) or homozygous for the reference allele (N = 16) (Figure 3).

The effect of the mutation at the cDNA and protein level have not examined, but the mutation is predicted to result in skipping of the 94-nucleotide exon 2 (out of 16 total exons), resulting in a frame shifted protein product beginning after amino acid 54 of the protein and terminating after the inclusion of 5 aberrant amino acids.

         <--exon 1       <--exon 2 intron 2-->       exon 3-->

258 ……AGCGCGCAGAAG ……GATGCTGTCAAAG gtaatggtttacaaa…… CTGCAGGGGTGCAGATGA……

51    -S--A--Q--K- ……-D--A--V--K--                   -L--Q--G--C--R--*-

        correct         deleted                           aberrant

 

Genomic numbering corresponds to NC_000075. The donor splice site of intron 2, which is destroyed by the barrener mutation, is indicated in blue lettering and the mutated nucleotide is indicated in red. 

Illustration of Mutations in
Gene & Protein
Protein Prediction

Figure 4. Domain organization of GK5. The location of the barrener mutation is indicated. Domain information is from SMART and UniProt. This image is interactive. Additional mutations in GK5 are noted. Click on each mutation to view more information.

The glycerol kinase 5 (putative) (Gk5) gene encodes the 534 amino acid (aa) GK5 protein. The protein domains and function of GK5 have not been documented. SMART predicts that this uncharacterized protein contains two domains that are found in the FGGY family of carbohydrate kinases. The FGGY kinases contain conserved motifs at both the N- and C-termini (Figure 4; aa 25-287 and aa 396-416 in GK5, respectively; SMART). The FGGY_N and FGGY_C termini are structurally similar and adopt a ribonuclease H-like fold (1;2). Between the FGGY_N and FGGY_C domains is a catalytic cleft where the sugar substrate and ATP bind (3). The barrener mutation is predicted to result in deletion of exon 2, which would result in a frame shifted protein product beginning after amino acid 54 of the protein and terminating after the inclusion of 5 aberrant amino acids.

For more information about Gk5, please see the entry for toku.

Putative Mechanism

The over 4,000 members of the FGGY family phosphorylate sugar substrates in an ATP-dependent manner (3). Similar to glycerol kinase, GK5 is proposed to be involved in ATP binding, phosphotransferase activity, and glycerol kinase activity. GK5 is necessary for hair growth, and functions in the regulation of SREBP-1/-2-mediated cholesterol production in the skin (4). The buildup of sterol precursors in the sebocytes results in defects in hair follicle development and homeostasis as observed in the barrener mice (4).

Primers PCR Primer
barrener_pcr_F: GGCTCTCTTTTCAAACAGTAAGG
barrener_pcr_R: AGGCAGAGTCTCCTAAGCAG

Sequencing Primer
barrener_seq_F: ACAGTAAGGATTAATTACATGCAACC
barrener_seq_R: GAGTCTCCTAAGCAGCTTAAACTG
Genotyping

PCR program

1) 94°C 2:00
2) 94°C 0:30
3) 55°C 0:30
4) 72°C 1:00
5) repeat steps (2-4) 40x
6) 72°C 10:00
7) 4°C hold


The following sequence of 490 nucleotides is amplified (chromosome 9, + strand):


1   ggctctcttt tcaaacagta aggattaatt acatgcaacc atgttactta ttttaaccag
61  tattttaaga tgccagtatt atcagctttg tctaatgcca ttctcactaa attttgtttt
121 catgaatagg tagaaaatgt ttaccctcaa cctggctggg ttgaaatcga tcctgattct
181 ctctgggctc agtttgttgc cgtaataaaa gatgctgtca aaggtaatgg tttacaaaga
241 gactgtcgtc cacagtggac ttcttcctga tgaattttcc acggattttg aggattacta
301 aatttataat acatacacta aatgtatata atatatatga ccttttatat atcatatata
361 tcacttatat atgatatata gaaatatata tttataaata tgaataaata atagacatac
421 aaacatattt ttaaatgtca cacaccaatt gtatttgaga tcagtttaag ctgcttagga
481 gactctgcct 


Primer binding sites are underlined and the sequencing primers are highlighted; the mutated nucleotide is shown in red.

References
Science Writers Anne Murray
Illustrators Katherine Timer
AuthorsZhao Zhang, Ying Wang, Hexin Shi, Doan Dao, Lei Sun, Jianhui Wang, Xiaoyu Wang, Ryan Solt, Bruce Beutler