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UniProtKB/Swiss-Prot Q8TCS8: Variant p.Ile121Val

Polyribonucleotide nucleotidyltransferase 1, mitochondrial
Gene: PNPT1
Variant information

Variant position:  121
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Type of variant:  Polymorphism
The variants are classified into three categories: Disease, Polymorphism and Unclassified.
  • Disease: Variants implicated in disease according to literature reports.
  • Polymorphism: Variants not reported to be implicated in disease.
  • Unclassified: Variants with uncertain implication in disease according to literature reports. Evidence against or in favor of a pathogenic role is limited and/or conflicting.

Residue change:  From Isoleucine (I) to Valine (V) at position 121 (I121V, p.Ile121Val).
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:  3
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

Other resources:  
Links to websites of interest for the variant.



Sequence information

Variant position:  121
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  783
The length of the canonical sequence.

Location on the sequence:   DYRQKAAAAGRIPTNYLRRE  I GTSDKEILTSRIIDRSIRPL
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                         DYRQKAAAAGRIPTNYLRREIGTSDKEILTSRIIDRSIRPL

Mouse                         DYRQKAAAAGRIPTNYLRREIGSSDREVLTSRVIDRSIRPL

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 46 – 783 Polyribonucleotide nucleotidyltransferase 1, mitochondrial
Mutagenesis 135 – 135 D -> G. Inhibits poly(A) polymerase and RNA degradation activities. Inhibits the import or stabilization of RNase P RNA into the mitochondrial matrix. Does not inhibit homotrimerization activity.


Literature citations

Protein-protein interactions between human exosome components support the assembly of RNase PH-type subunits into a six-membered PNPase-like ring.
Raijmakers R.; Vree Egberts W.; van Venrooij W.J.; Pruijn G.J.M.;
J. Mol. Biol. 323:653-663(2002)
Cited for: NUCLEOTIDE SEQUENCE [MRNA]; VARIANT VAL-121;

Identification and cloning of human polynucleotide phosphorylase, hPNPase (old-35), in the context of terminal differentiation and cellular senescence.
Leszczyniecka M.; Kang D.-C.; Sarkar D.; Su Z.-Z.; Holmes M.; Valerie K.; Fisher P.B.;
Proc. Natl. Acad. Sci. U.S.A. 99:16636-16641(2002)
Cited for: NUCLEOTIDE SEQUENCE [MRNA]; VARIANT VAL-121; FUNCTION; INDUCTION;

The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).
The MGC Project Team;
Genome Res. 14:2121-2127(2004)
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]; VARIANT VAL-121;

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.