title: LOXL3-sv2, a novel variant of human lysyl oxidase-like 3 (LOXL3), functions as an amine oxidase.
abstract: Human lysyl oxidase-like 3 (LOXL3) functions as a copper-dependent amine oxidase toward collagen and elastin. The LOXL3 protein contains four scavenger receptor cysteine-rich (SRCR) domains in the N-terminus in addition to the C-terminal characteristic domains of the lysyl oxidase (LOX) family, such as a copper-binding domain, a cytokine receptor‑like domain and residues for the lysyl-tyrosyl quinone cofactor. Using BLASTN searches, we identified a novel variant of LOXL3 (termed LOXL3-sv2), which lacked the sequences corresponding to exons 4 and 5 of LOXL3. The LOXL3-sv2 mRNA is at least 2,398 bp in length, encoding a 608 amino acid-long polypeptide with a calculated molecular mass of 67.4 kDa. The deletion of exons 4 and 5 do not change the open-reading frame of LOXL3 but results in deletion of the SRCR domain 2. The recombinant LOXL3-sv2 protein showed a β-aminopropionitrile-inhibitable amine oxidase activity toward collagen type I. In RT-PCR analysis, LOXL3-sv2 was detected in all human tissues tested, along with LOXL3 and LOXL3-sv1, a previously identified variant of LOXL3. These findings indicate that the human LOXL3 gene encodes at least three variants, LOXL3, LOXL3-sv1 and LOXL3-sv2, all of which function as amine oxidases.
authors.affiliation: Department of Biochemistry, Wonkwang University School of Medicine, Institute of Wonkwang Medical Science, Iksan, Jeonbuk 570-749, Republic of Korea.
authors.forename: Chankyu
authors.initials: C
authors.lastname: Jeong
authors.affiliation: Department of Biochemistry, Wonkwang University School of Medicine, Institute of Wonkwang Medical Science, Iksan, Jeonbuk 570-749, Republic of Korea.
authors.forename: Youngho
authors.initials: Y
authors.lastname: Kim
mesh_terms: D006631:Amine Oxidase (Copper-Containing) / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000594:Amino Acid Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D004789:Enzyme Activation; D005091:Exons; D023061:Gene Order; D006801:Humans; D007438:Introns; D000072417:Protein Domains; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins
chemical_list: D012333:RNA, Messenger; D011994:Recombinant Proteins; D000594:Amino Acid Oxidoreductases; C435668:LOXL3 protein, human; D006631:Amine Oxidase (Copper-Containing)