Note that this locus is complex: it appears to produce several proteins with no sequence overlap.
Expression: According to AceView, this gene is well expressed, 0.5 times the average gene in this release. The sequence of this gene is defined by 57 GenBank accessions from 54 cDNA clones, some from skin (seen 9 times), brain (6), melanotic melanoma (4), melanotic melanoma, cell line (4), eye (3), fetal brain (3), lung (3) and 35 other tissues. We annotate structural defects or features in 4 cDNA clones.
Alternative mRNA variants and regulation: The gene contains 14 distinct introns (13 gt-ag, 1 gc-ag). Transcription produces 8 different mRNAs, 6 alternatively spliced variants and 2 unspliced forms. There are 3 probable alternative promotors (see the diagram). The mRNAs appear to differ by truncation of the 5' end, presence or absence of 2 cassette exons, overlapping exons with different boundaries, splicing versus retention of 2 introns.
2 variants were isolated in vivo, despite the fact that they are predicted targets of nonsense mediated mRNA decay (NMD).
Function: There are 17 articles specifically referring to this gene in PubMed. Functionally, the gene has been tested for association to diseases (Breast Neoplasms; Carcinoma) and proposed to participate in processes (metabolic process, proteolysis). Proteins are expected to have molecular functions (calcium ion binding, metalloendopeptidase activity, zinc ion binding) and to localize in various compartments (cytoplasm, mitochondrion, anchored to membrane, extracellular region, plasma membrane, proteinaceous extracellular matrix). Putative protein interactors have been described (LRP1, MMP2, TNF).
Protein coding potential: 6 spliced mRNAs putatively encode good proteins, altogether 6 different isoforms (2 complete, 3 COOH complete, 1 partial), some containing domains Hemopexin, Matrixin, Putative peptidoglycan binding domain [Pfam]. The remaining 2 mRNA variants (2 unspliced; 2 partial) appear not to encode good proteins.
3 isoforms are annotated using as Met a Kozak-compatible non-AUG start, thereby gaining a minimum of 65 amino acids N-terminal to the first AUG. Finally proteins from this gene may be modulated by phosphorylation, as detailed at PhosphoSite.

Please quote: AceView: a comprehensive cDNA-supported gene and transcripts annotation, Genome Biology 2006, 7(Suppl 1):S12

Alternative mRNAs are shown aligned from 5' to 3' on a virtual genome where introns have been shrunk to a minimal length. Exon size is proportional to length, intron height reflects the number of cDNAs supporting each intron, the small numbers show the support of the introns in deep sequencing (with details in mouse-over) . Introns of the same color are identical, of different colors are different. 'Good proteins' are pink, partial or not-good proteins are yellow, uORFs are green. 5' cap or3' poly A flags show completeness of the transcript.
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