Cloning and characterization of a third human lysyl hydroxylase isoform.
Publication/Presentation Date
9-1-1998
Abstract
Lysyl hydroxylase (EC 1.14.11.4), a homodimer, catalyzes the formation of hydroxylysine in collagens. Recently, an isoenzyme termed lysyl hydroxylase 2 has been cloned from human sources [M. Valtavaara, H. Papponen, A.-M. Pirttilä, K. Hiltunen, H. Helander and R. Myllylä (1997) J. Biol. Chem. 272, 6831-6834]. We report here on the cloning of a third human lysyl hydroxylase isoenzyme, termed lysyl hydroxylase 3. The cDNA clones encode a 738 amino acid polypeptide, including a signal peptide of 24 residues. The overall amino acid sequence identity between the processed human lysyl hydroxylase 3 and 1 polypeptides is 59%, and that between the processed lysyl hydroxylase 3 and 2 polypeptides is 57%, whereas the identity to the processed Caenorhabditis elegans polypeptide is only 45%. All four recently identified critical residues at the catalytic site, two histidines, one aspartate, and one arginine, are conserved in all these polypeptides. The mRNA for lysyl hydroxylase 3 was found to be expressed in a variety of tissues, but distinct differences appear to exist in the expression patterns of the three isoenzyme mRNAs. Recombinant lysyl hydroxylase 3 expressed in insect cells by means of a baculovirus vector was found to be more soluble than lysyl hydroxylase 1 expressed in the same cell type. No differences in catalytic properties were found between the recombinant lysyl hydroxylase 3 and 1 isoenzymes. Deficiency in lysyl hydroxylase 1 activity is known to cause the type VI variant of the Ehlers-Danlos syndrome, and it is therefore possible that deficiency in lysyl hydroxylase 3 activity may lead to some other variant of this syndrome or to some other heritable connective tissue disorder.
Volume
95
Issue
18
First Page
10482
Last Page
10486
ISSN
0027-8424
Published In/Presented At
Passoja, K., Rautavuoma, K., Ala-Kokko, L., Kosonen, T., & Kivirikko, K. I. (1998). Cloning and characterization of a third human lysyl hydroxylase isoform. Proceedings of the National Academy of Sciences of the United States of America, 95(18), 10482–10486. https://doi.org/10.1073/pnas.95.18.10482
Disciplines
Medicine and Health Sciences
PubMedID
9724729
Department(s)
Department of Pathology and Laboratory Medicine
Document Type
Article