Biology:Yeast mitochondrial code

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Short description: An alternative genetic code found in the mitochondrial genome of yeasts

The yeast mitochondrial code (translation table 3) is a genetic code used by the mitochondrial genome of yeasts, notably Saccharomyces cerevisiae, Candida glabrata, Hansenula saturnus, and Kluyveromyces thermotolerans.[1]

The code

   AAs = FFLLSSSSYY**CCWWTTTTPPPPHHQQRRRRIIMMTTTTNNKKSSRRVVVVAAAADDEEGGGG
Starts = ---M---------------M---------------M---------------M------------
 Base1 = TTTTTTTTTTTTTTTTCCCCCCCCCCCCCCCCAAAAAAAAAAAAAAAAGGGGGGGGGGGGGGGG
 Base2 = TTTTCCCCAAAAGGGGTTTTCCCCAAAAGGGGTTTTCCCCAAAAGGGGTTTTCCCCAAAAGGGG
 Base3 = TCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAGTCAG

Bases: adenine (A), cytosine (C), guanine (G) and thymine (T) or uracil (U).

Amino acids: Alanine (Ala, A), Arginine (Arg, R), Asparagine (Asn, N), Aspartic acid (Asp, D), Cysteine (Cys, C), Glutamic acid (Glu, E), Glutamine (Gln, Q), Glycine (Gly, G), Histidine (His, H), Isoleucine (Ile, I), Leucine (Leu, L), Lysine (Lys, K), Methionine (Met, M), Phenylalanine (Phe, F), Proline (Pro, P), Serine (Ser, S), Threonine (Thr, T), Tryptophan (Trp, W), Tyrosine (Tyr, Y), Valine (Val, V).

Differences from the standard code

DNA codons RNA codons This code (3) Standard code (1)
ATA AUA Met (M) Ile (I)
CTT CUU Thr (T) Leu (L)
CTC CUC Thr (T) Leu (L)
CTA CUA Thr (T) Leu (L)
CTG CUG Thr (T) Leu (L)
TGA UGA Trp (W) STOP = Ter (*)
CGA CGA Absent Arg (R)
CGC CGC Absent Arg (R)
  • The remaining CGN codons are rare in Saccharomyces cerevisiae[2] and absent in Candida glabrata.
  • The AUA codon is common in the gene var1 coding for the single mitochondrial ribosomal protein, but rare in genes encoding the enzymes.
  • The coding assignments of the AUA (Met or Ile) and CUU (possibly Leu, not Thr) are uncertain in Hansenula saturnus.
  • The coding assignment of Thr to CUN is uncertain in Kluyveromyces thermotolerans.

See also

References

This article incorporates text from the United States National Library of Medicine, which is in the public domain. [3]

  1. Clark-Walker, G. D.; Weiller, G. F. (1994). "The structure of the small mitochondrial DNA of Kluyveromyces thermotolerans is likely to reflect the ancestral gene order in fungi". Journal of Molecular Evolution 38 (6): 593–601. doi:10.1007/bf00175879. PMID 8083884. Bibcode1994JMolE..38..593C. 
  2. Susan G. Bonitz, Roberta Berlani, Gloria Coruzzi, May Li, Giuseppe Macino, Francisco G. Nobrega, Marina P. Nobrega, Arbara E. Thalenfeld and Alexander Tzagoloff (June 1980). "Codon recognition rules in yeast mitochondria". Proc. Natl. Acad. Sci. USA 77 (6): 3167–3170. doi:10.1073/pnas.77.6.3167. PMID 6997870. PMC 349575. Bibcode1980PNAS...77.3167B. http://www.pnas.org/content/77/6/3167.full.pdf. 
  3. Elzanowski, Andrzej; Ostell, Jim; Leipe, Detlef; Soussov, Vladimir. "The Genetic Codes". Taxonomy browser. National Center for Biotechnology Information (NCBI), U.S. National Library of Medicine. https://www.ncbi.nlm.nih.gov/Taxonomy/taxonomyhome.html/index.cgi?chapter=tgencodes#thetop.