Structure, chromosomal localization, and promoter analysis of the human elastin microfibril interfase located proteIN (EMILIN) gene.

Abstract

Elastin microfibril interfase-located protein (EMILIN) is an extracellular matrix glycoprotein abundantly expressed in elastin-rich tissues such as the blood vessels, skin, heart, and lung. It occurs with elastic fibers at the interface between amorphous elastin and microfibrils. In vitro experiments suggested a role for EMILIN in the process of elastin deposition. This multimodular protein consists of 995 amino acids; the domain organization includes a C1q-like globular domain at the C terminus, a short collagenous stalk, a region containing two leucine zippers, and at least four heptad repeats with a high potential for forming coiled-coil alpha-helices and, at the N terminus, a cysteine-rich sequence characterized by a partial epidermal growth factor-like motif and homologous to a region of multimerin. Here we report the complete characterization of the human and murine EMILIN gene, their chromosomal assignment, and preliminary functional data of the human promoter. A cDNA probe corresponding to the C terminus of EMILIN was used to isolate two genomic clones from a human BAC library. Sequencing of several derived subclones allowed the characterization of the whole gene that was found to be about 8 kilobases in size and to contain 8 exons and 7 introns. The internal exons range in size from 17 base pairs to 1929 base pairs. All internal intron/exon junctions are defined by canonical splice donor and acceptor sites, and the different domains potentially involved in the formation of a coiled-coil structure are clustered in the largest exon. The 3'-end of the EMILIN gene overlaps with the 5'-end of the promoter region of the ketohexokinase gene, whose chromosomal position is between markers D2S305 and D2S165 on chromosome 2. A 1600-base pair-long sequence upstream of the translation starting point was evaluated for its promoter activity; five deletion constructs were assayed after transfection in primary chicken fibroblasts and in a human rhabdomyosarcoma cell line. This analysis indicates the existence of two contiguous regions able to modulate luciferase expression in both cell types used, one with a strong activatory function, ranging from positions -204 to -503, and the other, ranging from positions -504 to -683, with a strong inhibitory function.

• Authors: R Doliana, A Canton, F Bucciotti, M Mongiat, P Bonaldo, A Colombatti
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 275 Issue 2 Pg. 785-92 (Jan 14 2000) ISSN: 0021-9258 [Print] United States
• PMID: 10625608 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• 5' Untranslated Regions
• Extracellular Matrix Proteins
• Genetic Markers
• Membrane Glycoproteins
• elastin microfibril interface located protein
• Complement C1q
• Luciferases

Topics

• 5' Untranslated Regions
• Amino Acid Sequence
• Animals
• Base Sequence
• Chromosome Mapping
• Chromosomes, Human, Pair 2
• Complement C1q (chemistry)
• Exons
• Extracellular Matrix Proteins (genetics)
• Genetic Markers
• Humans
• Introns
• Luciferases (biosynthesis, genetics)
• Membrane Glycoproteins (genetics)
• Mice
• Molecular Sequence Data
• Promoter Regions, Genetic
• RNA Splicing
• Sequence Deletion