title: Signatures of positive selection at hemopexin (PEX) domain of matrix metalloproteinase-9 (MMP-9) gene.
abstract: Matrix metalloproteinases-9 (MMP-9) is an important cancer-associated, zinc-dependent endopeptidase. To investigate the natural selection hypothesis of MMP-9, the orthologous sequences from 12 vertebrates were compared and a molecular evolution analysis was performed. Results suggest that amino acid residues present in the middle region of the protein are more selectively constrained, whereas amino acid residues in the C-terminal region of the MMP-9 protein including exon 13 showed lowest conservation level in non-primate species, suggesting that it is an exon with fast evolving rate compared to the others analyzed. InterProScan analysis shows that exon 13 was located in hemopexin (PEX) domain of MMP-9. Positive selection was detected in PEX domain of MMP-9 protein between human and other species, which indicates that selective pressure may play a role in shaping the function of MMP-9 in the course of evolution.
authors.affiliation: Shanghai Institute of Quality Inspection and Technical Research/National Quality Supervision and Inspection Center for Food Products (Shanghai), Shanghai 200233, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Chunlei
authors.initials: C
authors.lastname: Lu
authors.forename: Maobin
authors.initials: M
authors.lastname: Fu
authors.forename: Tonghai
authors.initials: T
authors.lastname: Dou
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Tan
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019143:Evolution, Molecular; D005091:Exons; D006466:Hemopexin / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D012641:Selection, Genetic; D014714:Vertebrates
chemical_list: D006466:Hemopexin; D020780:Matrix Metalloproteinase 9