title: Precursor of egg white ovomucoid. Amino acid sequence of an NH2-terminal extension.
abstract: The translation of ovomucoid mRNA in a reticulocyte lysate protein-synthesizing system yields a precursor form which contains an NH2-terminal extension of 23 amino acid residues. Edman degradation of radioactive translation products (pre-ovomucoid) identified the following sequence: formula : (see text), where the initiator methionine (in parentheses) is the only residue cleaved from the NH2 terminus during cell-free synthesis and the vertical line indicates the site at which pre-ovomucoid is cleaved in vivo to yield ovomucoid. The precursor sequence differs from those of two other proteins (pre-lysozyme and pre-conalbumin) secreted by the same cell, but resembles these and other secretory protein "signal peptides" in both length and hydrophobicity. Pre-ovomucoid does not interact with trypsin in the same manner as mature ovomucoid.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D004527:Egg Proteins / Q000096:biosynthesis; D004529:Egg White; D010057:Oviducts / Q000378:metabolism; D010059:Ovomucin / Q000096:biosynthesis; D011233:Precipitin Tests; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D012156:Reticulocytes / Q000378:metabolism
chemical_list: D004527:Egg Proteins; D012333:RNA, Messenger; D010059:Ovomucin