A NEW GENE WITH SEQUENCE AND STRUCTURAL SIMILARITY TO THE GENE ENCODING HUMAN LYSYL OXIDASE

We have isolated a number of recombinant clones from a human skin fibr oblast cDNA library that contain extensive sequence homology to severa l coding domains within the human lysyl oxidase mRNA. Using one of the se lysyl oxidase-like cDNAs, we obtained several overlapping genomic D NA recombinants. Restriction mapping and DNA sequence analysis reveale d that the complete sequence of the lysyl oxidase-like mRNA was encode d by seven exons distributed throughout 25 kilobases of genomic DNA. E xons 2-6 encoded the region of greatest homology to lysyl oxidase. The size of these five exons, moreover, was exactly the same as the size of the corresponding exons within the lysyl oxidase gene. Northern blo t analysis also revealed the concomitant appearance of lysyl oxidase a nd lysyl oxidase-like mRNA in several human tissues. It appears theref ore that the genes encoding lysyl oxidase and a lysyl oxidase-like pro tein share a common evolutionary origin and may also be functionally r elated.