PUBLICATION

Sequencing of amphioxus PSMB5/8 gene and phylogenetic position of agnathan sequences

Authors
Takezaki, N., Zaleska-Rutczynska, Z., and Figueroa, F.
ID
ZDB-PUB-031204-22
Date
2002
Source
Gene   282(1-2): 179-187 (Journal)
Registered Authors
Figueroa, Felipe
Keywords
Adaptive immune system; Proteasome subunit; LMP; Genome duplication
MeSH Terms
  • Amino Acid Sequence
  • Animals
  • Chordata, Nonvertebrate/genetics*
  • Cysteine Endopeptidases/genetics*
  • DNA, Complementary/chemistry
  • DNA, Complementary/genetics
  • Endopeptidases/genetics
  • Lampreys/genetics*
  • Molecular Sequence Data
  • Multienzyme Complexes/genetics*
  • Phylogeny*
  • Proteasome Endopeptidase Complex
  • Proteins/genetics*
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Zebrafish Proteins*
PubMed
11814690 Full text @ Gene
Abstract
Reanalyses of vertebrate PSMB5 and PSMB8 genes were conducted with a newly obtained amphioxus sequence. The phylogenetic analysis indicated that the amphioxus sequence is an outgroup of both vertebrate PSMB5 and PSMB8 genes. The agnathan sequences were previously thought to be closer to PSMB5 than PSMB8 sequences. However, in this study the phylogenetic trees supported the clustering of agnathan sequences with PSMB8 rather than with PSMB5 sequences. In the alignment there are many sites in which the agnathan sequences are more similar to PSMB5 than PSMB8 sequences. Parsimony analysis showed that the amino acid pattern at these sites could be explained by one substitution on the ancestral branch leading to the jawed vertebrate PSMB8 cluster. The number of substitutions required at these sites was the same for different tree topologies with respect to the position of agnathans. The phylogenetic analyses of PSMB6/PSMB9 and PSMB7/PSMB10 genes indicated that all the interferon-gamma-inducible forms have evolved two to three times faster than the housekeeping forms in the jawed vertebrate lineage. Hence although the agnathan sequences cluster with the PSMB8 sequences, they have a slower rate of evolution similar to that of the housekeeping forms, and may be functioning as housekeeping forms.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping