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- ****************************************
- * Proteasome B-type subunits signature *
- ****************************************
-
- The proteasome (or macropain) (EC 3.4.99.46) [1,2,3] is an eukaryotic and
- archaebacterial multicatalytic proteinase complex that seems to be involved in
- an ATP/ubiquitin-dependent nonlysosomal proteolytic pathway. In eukaryotes the
- proteasome is composed of about 24 distinct subunits which form a highly
- ordered ring-shaped structure (20S ring).
-
- Most proteasome subunits can be classified, on the basis on sequence
- similarities into two groups, A and B. Subunits that belong to the B-type
- group are proteins of from 210 to 290 amino acids that share a number of
- conserved sequence regions. Subunits that are known to belong to this family
- are listed below.
-
- - Vertebrate beta-subunit, delta-subunit, epsilon-subunit, LMP2/RING12 and
- C13 (LMP7/RING10)
- - Yeast PRE2, PRE4, PRG1, and PUP1.
- - Schizosaccharomyces pombe pts1.
- - Thermoplasma acidophilum beta-subunit. In this archaebacteria the
- proteasome is composed of only two different subunits.
-
- As a signature pattern for proteasome B-type subunits we selected the best
- conserved region, which is located in the N-terminal part of these proteins.
-
- -Consensus pattern: [LIVM]-[GSA]-[LIVMF]-[KRQET]-[FYL]-[DEQNKR]-x-[GA]-
- [VI](2)-[LIVMA]-[GAC]-[STAV]-[DE]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: October 1993 / First entry.
-
- [ 1] Rivett A.J.
- Biochem. J. 291:1-10(1993).
- [ 2] Rivett A.J.
- Arch. Biochem. Biophys. 268:1-8(1989).
- [ 3] Goldberg A.L., Rock K.L
- Nature 357:375-379(1992).
-