Roumanian Biotechnological Letters Vol. 13, No. 6, 2008, pp. 4066-4073 Copyright © 2008 Bucharest University Printed in Romania. All rights reserved Roumanian Society of Biological Sciences ORIGINAL PAPER 4066 CG6199 LH2a lethal allele from Drosophila melanogaster is a candidate model for investigations on Ehlers-Danlos syndrome Received for publication, September 1, 2008 Accepted, October 30, 2008 MARIAN GRAUR 1 , ALEXANDRU AL. ECOVOIU 1 , ATTILA CRISTIAN RATIU 1 , LORAND SAVU 2 , LUCIAN GAVRILA Corresponding author: Marian Graur, Institute of Genetics, University of Bucharest, Intrarea Portocalelor 1-3, 060101, phone number: 0040726318123, email: 1 1: Institute of Genetics, University of Bucharest, Aleea Portocalelor 1-3, sector 6, Bucharest, Romania. 2: Genetic Lab, str. Popa Rusu, sector 2, Bucharest, Romania. mariangraur@botanic.unibuc.ro Abstract CG6199 gene from Drosophila melanogaster is a structural orthologous of PLOD1 human gene, which encodes for a lysyl hydroxylase and is involved in Ehlers–Danlos syndrome type VI (the ocular type). In order to determine phenotypic consequences of CG6199 impairing, loss-of-function analysis was initiated and CG6199 LH2a embryo lethal allele was obtained by P element mutagenesis. This allele harbors an P{EP} transposon insertion into the 9 th exon of CG6199, encoding for an amino acid sequence belonging to the P4Hc functional domain of lysyl hydroxylase. Phenotypic and molecular analysis of CG6199 LH2a allele points that P4Hc is essential for the normal embryo development of D. melanogaster. Our data support a functional orthology between CG6199 and PLOD1 genes, creating premises for the study of Ehlers-Danlos syndrome using D. melanogaster experimental model. Keywords: Ehlers-Danlos syndrome, Drosophila melanogaster, PLOD1, CG6199, transposon mutagenesis. Introduction Ehlers-Danlos syndrome is an autosomal recessive disorder, characterized by hiperelastic skin, severe joints hipermobility and luxations, weakness of tissues and cardiovascular complications [1, 2]. In some cases of EDS syndrome type VI (the ocular type), a lysyl hydroxylase deficiency was reported, caused by mutations in PLOD1 human gene [3]. PLOD1 gene maps to 1p36.3-36.2 [4], has about 41 kb and 19 exons and encodes for lysyl hydroxylase ( LH1, procollagen lysine, 2-oxoglutarate 5 dioxygenase 1; EC1.14.11.4). This enzyme belongs to the group of 2-oxoglutarate dioxygenases or 2 OG- Fe(II) oxygenases, which also includes prolyl 4-hydroxylase alpha subunit, isopenicilin synthases and AlkB [5]. LH1 hydroxylates lysine residues during collagen synthesis, enabling them to serve as attachment sites for carbohydrate units, which confer stability of the intermolecular collagen crosslinks. The hydroxylation reaction catalyzed by lysyl hydroxilase requires Fe 2+ , 2-oxoglutarate, O 2 and ascorbate as essential cofactors and generates lysyl residues in procollagen polypeptide, CO 2 and succinate [6]. The deficiency of LH1 leads to a decrease in hydroxylysine content of collagen, resulting in synthesis of collagen that lacks normal structural stability. While the prevalence of this disease is low (1/5000-10000), it is recorded in every continent and affects both sexes [7].