Characterization of the human Notch ligand, Delta-4.
(A) Alignment of amino acids sequence of Delta-related proteins. The DSL domains and EGF-like repeats are marked by a black bar above alignment. The putative signal sequence (indicated with an arrow) and transmembrane domain are indicated as colored letters (red). The identical amino acids are shaded (yellow). Human Delta-1 (Gray et al, 1999) (hdel1; Genbank accession number AF003522); human Delta-4 (submitted to Genbank as human Delta-2, hdel2; Genbank accession number AF253468); X-Delta-2 (Jen et al, 1997) (xdel2; Genbank accession number U70843); and mouse D113 (Dunwoodie et al, 1997) (mdel3; Genbank accession number NM007866) represent Delta-related proteins. Human Delta-4 cDNA was isolated by cross-hybridization of hDelta-1 cDNA from fetal lung cDNA library. (B) Expression profile of hDelta-4 mRNA in tissues. As positive control, β-actin was used. For Northern blot analysis, a 32P-labeled human Delta-4 cDNA (412 bp) was used to hybridize to cDNA from various tissues of human origin.
