title: Age-dependent deamidation of the major intrinsic polypeptide from lens membranes.
abstract: The Major Intrinsic Polypeptide (MP26) of lens membranes contains an -asn-gly- sequence, which has been shown in other proteins to be particularly susceptible to spontaneous deamidation. To determine if the asparagine residue of this sequence undergoes age-dependent deamidation in vivo, antiserum to a synthetic peptide containing the sequence was used to monitor purification of a tryptic peptide containing this sequence from fetal versus mature bovine lenses. The peptide from fetal lenses contained the -asn-gly- sequence, while the peptide from mature lenses contained an -asp-gly- sequence, demonstrating that age-dependent deamidation of this asparagine residue was occurring in the lens.
authors.affiliation: Division of Biology, Kansas State University, Manhattan 66506.
authors.forename: L
authors.initials: L
authors.lastname: Takemoto
authors.forename: T
authors.initials: T
authors.lastname: Emmons
mesh_terms: D000375:Aging / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D020346:Aquaporins; D001216:Asparagine / Q000737:chemistry; D001224:Aspartic Acid / Q000737:chemistry; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D003641:Deamination; D005136:Eye Proteins / Q000737:chemistry* / Q000302:isolation & purification; D007908:Lens, Crystalline / Q000737:chemistry*; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D011499:Protein Processing, Post-Translational; D011863:Radioimmunoassay
chemical_list: D020346:Aquaporins; D005136:Eye Proteins; D008562:Membrane Glycoproteins; C030328:aquaporin 0; D001224:Aspartic Acid; D001216:Asparagine