|Mutation Type||splice site (15 bp from exon)|
|Coordinate||103,823,274 bp (GRCm38)|
|Base Change||A ⇒ T (forward strand)|
|Gene Name||endothelin receptor type B|
|Synonym(s)||ETb, ETR-b, Sox10m1|
|Chromosomal Location||103,814,625-103,844,402 bp (-)|
FUNCTION: This gene encodes a member of the G-protein coupled receptor family. It encodes a receptor for endothelins, peptides that are involved in vasocontriction. The encoded protein activates a phosphatidylinositol-calcium second messenger system and is required for the development of enteric neurons and melanocytes. Gene disruption causes pigmentation anomalies, deafness, and abnormal dilation of the colon due to defects of neural crest-derived cells. Mutations in this gene are found in the piebald mouse, and mouse models of Hirschsprung's disease and Waardenburg syndrome type 4. Renal collecting duct-specific gene deletion causes sodium retention and hypertension. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2013]
PHENOTYPE: Mice homozygous for null mutations have pigmentation limited to small patches on the head and rump and die from megacolon resulting from impaired neural crest migration and aganglionosis. Heterozygotes for a null allele show improved cardiac tolerance to hypoxia. [provided by MGI curators]
|Amino Acid Change|
|Institutional Source||Beutler Lab|
|Gene Model||predicted gene model for protein(s): [ENSMUSP00000022718 †] [ENSMUSP00000126057 †] [ENSMUSP00000154806 †] † probably from a misspliced transcript|
|Predicted Effect||probably null|
|Predicted Effect||probably null|
|Predicted Effect||probably null|
|Meta Mutation Damage Score||0.9755|
|Is this an essential gene?||Probably essential (E-score: 0.770)|
|Candidate Explorer Status||CE: failed initial filter|
Linkage Analysis Data
|Alleles Listed at MGI|
|Mode of Inheritance||Autosomal Recessive|
|Last Updated||2018-04-25 3:01 PM by Anne Murray|
|Record Created||2014-01-30 12:57 PM by Jennifer Weatherly|
The pongo phenotype was identified among N-ethyl-N-nitrosourea (ENU)-induced G3 mice of the pedigree R0591, some of which had a piebald appearance (i.e., a variable black and white spotting pattern) (Figure 1). Although they appear healthy at birth, the pongo mice die prematurely at or around weaning; cause of death has not been determined.
|Nature of Mutation|
Whole exome HiSeq sequencing of the G1 grandsire identified 61 mutations, one of which affected Ednrb, a gene known to cause pied spotting when mutated [(1); see MGI as well as the record for gus-gus]. The Ednrb mutation is a T to A transversion at base pair 103,823,274 (v38) on chromosome 14, or base pair 21,203 in the GenBank genomic region NC_000080 encoding Ednrb. The mutation is located near the acceptor site of intron 2, 15 nucleotides from the next exon. The effect of the mutation at the cDNA and protein levels has not been determined. One possibility, shown below, is that aberrant splicing may result in skipping of the 205 base pair exon 3 (out of 7 total exons), resulting in a frameshift and coding of 19 aberrant amino acids followed by a premature stop codon after amino acid 218.
<--exon 2 <--intron 2 exon 3--> exon 4-->
21072 ……CTAAGTATTGACAG ……tgtttatatcttcag ATATCGAGCTGTTGCT…… TTTTACAAGA……TCTGCTTGCCGCTAG
195 ……-L--S--I--D--S --Y--R--A--V--A-…… --F--T--R-……-S--A--C--R--* 218
correct deleted aberrant
Genomic numbering corresponds to NC_000080. The acceptor splice site of intron 2, which is destroyed by the mutation is indicated in blue; the mutated nucleotide is indicated in red.
|Illustration of Mutations in
Gene & Protein
Ednrb encodes endothelin receptor type B (ETBR), a member of the endothelin (ET) receptor family of rhodopsin-like G protein-coupled receptors (GPCRs; see the record for Bemr3) (2;3). The rhodopsin-like GPCRs have seven helical transmembrane domains, three extracellular and three intracellular loops, an extracellular N-terminus, and a cytoplasmic C-terminus (Figure 2). The pongo mutation is predicted to result in coding of a premature stop codon before transmembrane domain 4 of the ETBR.
Please see the record gus-gus for more information on Ednrb.
ET-associated signaling (ET-1/ETAR and ET-3/ETBR) is essential for neural crest (NC) cell proliferation, migration, differentiation, and transformation (4-6). The embryonic NC gives rise to pluripotent cells that migrate to different locations within the embryo during development (7). The NC cells subsequently differentiate into several cell types including adrenomedullary cells, craniofacial skeletal tissue, glia and some neurons of the peripheral nervous system, enteric neurons and glia, and melanocytes of the skin, hair and inner ear. ET-3/ETBR-associated signaling is required between embryonic day (E)10-E12.5 in the mouse for the survival and migration of enteric ganglion neurons and melanocytes derived from trunk/vagal NC cells (1;5;6;8-10). Other studies indicate that ETBR signaling may also stimulate melanocyte proliferation in the epidermis (11). Mice homozygous for targeted as well as naturally occurring Ednrb null mutations (e.g., MGI:1856148, MGI:1856149, MGI:1857161, and MGI:3795226) exhibit a piebald appearance due to the absence of NC-derived melanocytes in the epidermis (1;9;12-14). Ednrb null mice also exhibit an absence of choroidal melanocytes; neuroectoderm-derived pigment epithelium melanocytes develop normally (1). Ednrb null mice display early postnatal lethality [from ~postnatal day 15 to up to seven weeks after birth; (1;12;14)]. Similar to spontaneous and targeted Ednrb knockout mouse models, the pongo mice exhibit a piebald appearance and early postnatal lethality. The Ednrb knockout mouse models have established that the observed pigmentation defects are due to the absence of NC-derived melanocytes in the hair bulbs of non-pigmented areas (1;9;12-14).
Pongo genotyping is performed by amplifying the region containing the mutation using PCR, followed by sequencing of the amplified region to detect the single nucleotide transversion.
Pongo (F): 5’- GCAAAGTGAACGTACCTGCATGAAG-3’
Pongo (R): 5’- TTAATCACCGGCACTCAGTGCTC-3’
Pongo (F): 5’- CATGAAGGCTGTTTTCTGAAAGG-3’
Pongo (R): 5’- AAGCTGGTGCCCTTCATACAG-3’
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 ∞
The following sequence of 535 nucleotides is amplified (Chr.14: 103823040-103823574, GRCm38; NC_000080):
gcaaagtgaa cgtacctgca tgaaggctgt tttctgaaag ggattaagca tgcagaccct
taggggcttt cctttgtagt ccgacgtaat catatcaaaa cctatggctt cggggacagc
cagaaccaca gagaccaccc aaattaaaac aatttctact gctgtccatt ttggaacccc
aattccttta attcgactcc aagaagcaac agctcgatat ctgaagatat aaacagaatg
atttgtctag caggtagagc ttggttgtat tgaattgcaa agtttatctc ctaagtgaca
taacagttgt atgttggatt aggatcgcct tggcctgaga atagactctt acctgtcaat
acttagagca caaagactca gcactgtgat tcccacagaa gccttctgta tgaagggcac
cagcttacac atctcagctc caaatggcca gtcctctgcg agcaactgca tagaggaaac
gggaaggtcg gttacggaga tttttctgag ctgagcactg agtgccggtg attaa
Primer binding sites are underlined and the sequencing primer is highlighted; the mutated nucleotide (A) is shown in red text (Chr. + strand, A>T; sense strand, T>A).
1. Hosoda, K., Hammer, R. E., Richardson, J. A., Baynash, A. G., Cheung, J. C., Giaid, A., and Yanagisawa, M. (1994) Targeted and Natural (Piebald-Lethal) Mutations of Endothelin-B Receptor Gene Produce Megacolon Associated with Spotted Coat Color in Mice. Cell. 79, 1267-1276.
2. Nakamuta, M., Takayanagi, R., Sakai, Y., Sakamoto, S., Hagiwara, H., Mizuno, T., Saito, Y., Hirose, S., Yamamoto, M., and Nawata, H. (1991) Cloning and Sequence Analysis of a cDNA Encoding Human Non-Selective Type of Endothelin Receptor. Biochem Biophys Res Commun. 177, 34-39.
3. Arai, H., Hori, S., Aramori, I., Ohkubo, H., and Nakanishi, S. (1990) Cloning and Expression of a cDNA Encoding an Endothelin Receptor. Nature. 348, 730-732.
4. Pla, P., and Larue, L. (2003) Involvement of Endothelin Receptors in Normal and Pathological Development of Neural Crest Cells. Int J Dev Biol. 47, 315-325.
5. Shin, M. K., Levorse, J. M., Ingram, R. S., and Tilghman, S. M. (1999) The Temporal Requirement for Endothelin Receptor-B Signalling during Neural Crest Development. Nature. 402, 496-501.
6. Kurihara, H., Kurihara, Y., Nagai, R., and Yazaki, Y. (1999) Endothelin and Neural Crest Development. Cell Mol Biol (Noisy-le-grand). 45, 639-651.
7. Stanchina, L., Baral, V., Robert, F., Pingault, V., Lemort, N., Pachnis, V., Goossens, M., and Bondurand, N. (2006) Interactions between Sox10, Edn3 and Ednrb during Enteric Nervous System and Melanocyte Development. Dev Biol. 295, 232-249.
8. Baynash, A. G., Hosoda, K., Giaid, A., Richardson, J. A., Emoto, N., Hammer, R. E., and Yanagisawa, M. (1994) Interaction of Endothelin-3 with Endothelin-B Receptor is Essential for Development of Epidermal Melanocytes and Enteric Neurons. Cell. 79, 1277-1285.
9. Lee, H. O., Levorse, J. M., and Shin, M. K. (2003) The Endothelin Receptor-B is Required for the Migration of Neural Crest-Derived Melanocyte and Enteric Neuron Precursors. Dev Biol. 259, 162-175.
10. Zaitoun, I., Erickson, C. S., Barlow, A. J., Klein, T. R., Heneghan, A. F., Pierre, J. F., Epstein, M. L., and Gosain, A. (2013) Altered Neuronal Density and Neurotransmitter Expression in the Ganglionated Region of Ednrb Null Mice: Implications for Hirschsprung's Disease. Neurogastroenterol Motil. 25, e233-44.
11. Yoshida, H., Kunisada, T., Kusakabe, M., Nishikawa, S., and Nishikawa, S. I. (1996) Distinct Stages of Melanocyte Differentiation Revealed by Anlaysis of Nonuniform Pigmentation Patterns. Development. 122, 1207-1214.
12. Matsushima, Y., Shinkai, Y., Kobayashi, Y., Sakamoto, M., Kunieda, T., and Tachibana, M. (2002) A Mouse Model of Waardenburg Syndrome Type 4 with a New Spontaneous Mutation of the Endothelin-B Receptor Gene. Mamm Genome. 13, 30-35.
13. Dunn, L. C., and Charles, D. R. (1937) Studies on Spotting Patterns I. Analysis of Quantitative Variations in the Pied Spotting of the House Mouse. Genetics. 22, 14-42.
|Science Writers||Anne Murray|
|Authors||Carlos Reyna Tiana Purrington|