UniProtKB/Swiss-Prot O14746: Variant p.Val170Met

Telomerase reverse transcriptase
Gene: TERT
Chromosomal location: 5p15.33
Variant information

Variant position:  170
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Type of variant:  Disease [Disclaimer]
The variants are classified into three categories: Disease, Polymorphism and Unclassified.
  • Disease: Variants have been found in patients and disease-association is reported in literature. However, this classification is not a definitive assessment of variant pathogenicity.
  • Polymorphism: No disease-association has been reported.
  • Unclassified: Variants have been found in patients but disease-association remains unclear.

Residue change:  From Valine (V) to Methionine (M) at position 170 (V170M, p.Val170Met).
Indicates the amino acid change of the variant. The one-letter and three-letter codes for amino acids used in UniProtKB/Swiss-Prot are those adopted by the commission on Biochemical Nomenclature of the IUPAC-IUB.

Physico-chemical properties:  Similar physico-chemical property. Both residues are medium size and hydrophobic.
The physico-chemical property of the reference and variant residues and the change implicated.

BLOSUM score:  1
The score within a Blosum matrix for the corresponding wild-type to variant amino acid change. The log-odds score measures the logarithm for the ratio of the likelihood of two amino acids appearing by chance. The Blosum62 substitution matrix is used. This substitution matrix contains scores for all possible exchanges of one amino acid with another:
  • Lowest score: -4 (low probability of substitution).
  • Highest score: 11 (high probability of substitution).
More information can be found on the following page

Involvement in disease:  Pulmonary fibrosis, and/or bone marrow failure, telomere-related, 1 (PFBMFT1) [MIM:614742]: A disease associated with shortened telomeres. Pulmonary fibrosis is the most common manifestation. Other manifestations include aplastic anemia due to bone marrow failure, hepatic fibrosis, and increased cancer risk, particularly myelodysplastic syndrome and acute myeloid leukemia. Phenotype, age at onset, and severity are determined by telomere length. Note=The disease is caused by mutations affecting the gene represented in this entry.
The name and a short description of the disease associated with the variant. For more information about the disease, the user can refer to OMIM, following the link provided after the disease acronym.

Variant description:  In PFBMFT1; the mutant protein is demonstrated to cause decreased telomerase activity.
Any additional useful information about the variant.



Sequence information

Variant position:  170
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  1132
The length of the canonical sequence.

Location on the sequence:   VHLLARCALFVLVAPSCAYQ  V CGPPLYQLGAATQARPPPHA
The residue change on the sequence. Unless the variant is located at the beginning or at the end of the protein sequence, both residues upstream (20) and downstream (20) of the variant will be shown.

Residue conservation: 
The multiple alignment of the region surrounding the variant against various orthologous sequences.

Human                         VHLLARCALFVLVAPSCAYQVCGPPLYQLGAAT------QA--RPPPHA

Mouse                         VYLLAHCALYLLVPPSCAYQVCGSPLYQICATTDIWPSVSA

Rat                           VYLLSHCALYLLVPPSCAYQVCGSPLYQICATTDTWSSVPA

Bovine                        THLLSRCALYLLVPPTCAYQVCGPPLYDLRAAA------AA

Dog                           THLLARCALYLLVAPSCAYQVCGPPLYDLCAPA------SL

Baker's yeast                 VDLLINYTV-IQFNGQFFTQIVG------------------

Fission yeast                 HYLLSKGSIFEALPNDNYLQISGIPLF--------------

Sequence annotation in neighborhood:  
The regions or sites of interest surrounding the variant. In general the features listed are posttranslational modifications, binding sites, enzyme active sites, local secondary structure or other characteristics reported in the cited references. The "Sequence annotation in neighborhood" lines have a fixed format:
  • Type: the type of sequence feature.
  • Positions: endpoints of the sequence feature.
  • Description: contains additional information about the feature.

TypePositionsDescription
Chain 1 – 1132 Telomerase reverse transcriptase
Region 1 – 230 RNA-interacting domain 1
Region 58 – 197 GQ motif
Site 169 – 169 Required for optimal binding of telomeric ssDNA and incorporation of nucleotides at the second position of the template
Mutagenesis 169 – 169 Q -> A. About 80% loss of enzymatic activity. Greatly reduced incorporation of second nucleotide. Altered strength of binding to ssDNA. Little effect on repeat addition processivity, nor on TR interaction nor on protein levels.
Mutagenesis 169 – 169 Q -> N. About 85% loss of enzymatic activity. Greatly reduced incorporation of second nucleotide. Altered strength of binding to ssDNA. No effect on protein levels nor on TR interaction.
Mutagenesis 169 – 169 Q -> T. About 90% loss of enzymatic activity. Greatly reduced incorporation of second nucleotide. Altered strength of binding to ssDNA. No effect on protein levels nor on TR interaction.


Literature citations

Syndrome complex of bone marrow failure and pulmonary fibrosis predicts germline defects in telomerase.
Parry E.M.; Alder J.K.; Qi X.; Chen J.J.; Armanios M.;
Blood 117:5607-5611(2011)
Cited for: VARIANTS PFBMFT1 MET-170; THR-716; PHE-841; ARG-902 AND PHE-1025; CHARACTERIZATION OF VARIANTS PFBMFT1 MET-170; THR-716; PHE-841 AND PHE-1025;

Disclaimer: Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. They are not in any way intended to be used as a substitute for professional medical advice, diagnostic, treatment or care.