Genomic organisation, alternative splicing and primary structure of human matrilin-4.
We have recently cloned a cDNA for mouse matrilin-4. By sequence comparison we identified the 12 kb long human matrilin-4 gene as a part of a high-throughput genomic sequence (HS453C12) in the databases. Additionally we found a human matrilin-4 expressed sequence tag (H54037) in the database that had been mapped to chromosome 20q13.1-2. The gene contains 10 exons and, like the matrilin-1 gene, the human matrilin-4 gene contains an AT-AC intron between the two exons encoding the coiled-coil domain. The cDNA sequence of human matrilin-4 was determined by sequencing of RT-PCR products obtained from mRNA of the human embryonic kidney cell line HEK 293. At the amino acid level it showed an overall sequence identity to the mature mouse matrilin-4 of 91% with a maximum of 97% in the second vWFA-like module. Alternative splicing leads to three different mRNAs. They all encode the putative signal peptide, the two vWFA-like domains and the potential coiled-coil alpha-helical oligomerisation domain but differ in that either one, two or three EGF-like domains are retained in the mature mRNA. Due to a G to A mutation at the splice donor site of intron C, the third exon encodes an untranslated pseudo-exon specifying the first EGF-like domain when compared to mouse matrilin-4.
Wagener
R
R
Institute for Biochemistry II, Medical Faculty, University of Cologne, Germany. raimund.wagener@uni-koeln.de
Kobbe
B
B
Paulsson
M
M
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D002890:Chromosomes, Human, Pair 20; D018076:DNA, Complementary; D019992:Databases as Topic; D005091:Exons; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics*; D014644:Genetic Variation; D006801:Humans; D007438:Introns; D046911:Macromolecular Substances; D064235:Matrilin Proteins; D051379:Mice; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
D018076:DNA, Complementary; D016326:Extracellular Matrix Proteins; C577548:MATN4 protein, human; D046911:Macromolecular Substances; C577547:Matn4 protein, mouse; D064235:Matrilin Proteins